Search

Background: Klebsiella pneumoniae (K. pneumoniae) is a major cause of nosocomial and community-acquired infections (CAIs). Understanding the antibiotic susceptibility of this bacterium is essential for selecting the most effective antibiotic for associated infections. Objectives: We investigated the sensitivity of K. pneumonia (KP) isolates obtained from inpatients in Isfahan, Iran. Methods: Organism identification and antibiotic susceptibility testing were conducted using standard tests. Stratification was performed based on extended spectrum beta-lactamase (ESBL) production and the source of infection acquisition (community versus hospital). Results: A total of 437 KP isolates were investigated, of which 5.5% were pan drug resistant (PDR), 56.8% were extensively drug resistant (XDR), and 18% were ESBL producers. The isolates were most susceptible to colistin (100%), aminoglycosides (62.8%), and carbapenems (55%). Nosocomial isolates showed lower sensitivity to most of the examined antibiotics. Conclusions: The high prevalence of PDR and XDR KP strains in hospitalized patients is a major problem in the studied area. [ABSTRACT FROM AUTHOR]

Background: Spontaneous bacterial peritonitis (SBP) is a fatal complication of ascites fluid infection. The causes of SBP in children differ from those in adults, and these bacteria are frequently resistant to antibiotics. Therefore, this study investigated the clinical findings, bacterial etiology, and antimicrobial resistance in children with SBP. Methods: This study was conducted on all new pediatric ascites patients, who were admitted to the Department of Pediatric Gastroenterology, Namazi Hospital, affiliated with Shiraz University of Medical Sciences (Shiraz, Iran) from 2021 to 2022. Required data such as demographic information, and clinical information such as complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Gram staining, blood culture by Automated Blood Culture System (BACTEC), and antibiogram of ascites fluids by disc diffusion method were all collected. Finally, the data were statistically analyzed using SPSS Software (version 26). Besides, the t test, Fisher's exact, Mann- Whitney, and Chi square tests were used for data analysis. In all tests, P≤0.05 was considered statistically significant. Results: The present study examined 62 children with ascites of which 18 (29%) had SBP. The median (IQR) age was 2.5 (8.1) years. Thirty-four (54.8%) of the participants were girls. Abdominal pain was the most common clinical manifestation in patients (54%), and there was a significant association between abdominal pain and SBP (P=0.02). In 12 positive ascites fluid cultures, coagulase-negative staphylococci had the highest frequency (25%), followed by Escherichia coli (16.7%). Thirdgeneration cephalosporins had a 25% sensitivity in the total positive cultures. This sensitivity was 33.3% for Gram-negative cultures and 16.6% for Gram-positive cultures. Conclusion: Although third-generation cephalosporins are recommended as the primary antibiotic for the empirical treatment of SBP, the present study found high bacterial resistance. Finally, empirical therapy should be tailored to each region's bacterial resistance features. [ABSTRACT FROM AUTHOR]

Background and Objectives: During the coronavirus pandemic, the overuse of antibiotics to reduce coinfections and mortality may be contributing to the rise of antimicrobial resistance. In this study, we aim to investigate the antibiotic resistance changes of Acinetobacter baumannii post-COVID-19 pandemic in Northern Iran. Materials and Methods: The current study is a cross-sectional study. Between 2022 and 2023, 2190 clinical samples were collected from patients with healthcare-associated infections (HAIs) at four hospitals in Sari, which served as corona centers after the COVID-19 pandemic. Antimicrobial sensitivity was determined using standard broth macro-dilution, and resistance genes were detected using multiplex PCR. Results: Based on the results co-amoxiclav had a resistance rate of 100%, while piperacillin/tazobactam showed the least resistance rate of 29.82%. In terms of GM MIC values, colistin was the most potent against multi-drug resistant isolates. The frequency of bla OXA-51, ampC, aphA6, and bla NDM genes were 100%, 99.12%, 90.35%, and 69.30% respectively. Conclusion: Our study revealed high multi-drug resistance rates. Piperacillin/tazobactam recommended for treating multidrug resistant Acinetobacter baumannii infections in Northern Iran. [ABSTRACT FROM AUTHOR]

Background and Aims: Multidrug and extensive drug‐resistant Pseudomonas aeruginosa was extracted from burn patients referring to burn centers in southwest Iran so that biofilm generation and antibiotic resistance could be investigated. Methods: A specific primer was used to confirm all our considered 110 P. aeruginosa culture‐positive reports on 345 burn patients. The resistance of P. aeruginosa to seven antibiotics and Colistin with minimum inhibitory concentration (MIC) was assessed. Biofilm formation was assessed by the phenotypic study of specimens under Congo red agar and microtiter plate assays. Results: One hundred and 10 clinical P. aeruginosa isolates taken from burn wound infections were validated. Among P. aeruginosa isolates, Piperacillin, Ceftazidime, Maeropenem, Gentamycin, and Gatifloacin had the highest resistance to antibiotics, while Ticarcillin‐Clavulanic acid and Ceftolozane‐Tazobactam showed the least resistance. MICs were then evaluated via the E test. Seven isolates were resistant to colistin. Colistin reference MICs for multidrug‐resistant P. aeruginosa prevalence was 38%, while it was 22% for extensively drug‐resistant (XDR) P. aeruginosa. One P. aeruginosa was pandrug‐resistant (PDR). Under Congo red agar test, 66 isolates (67%) formed biofilms and black colonies, whereas 44 isolates (50%) had red colonies. In MTP, 76% formed biofilm. 40%, 32%, 21% of the isolates were strong, moderate, and weak biofilm formers, respectively, while 43% did not form biofilms. Conclusion: The P. aeruginosa resistance to antimicrobial agents has largely challenged the control of the infection. Accordingly, a higher resistance occurred when the isolates were transferred to the patients. Less than 50% P. aeruginosa samples generated strong biofilms. Consequently, hygienic measurements are essential to inhibit P. aeruginosa transmission to hospitalized patients. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate secondary bacterial infections among patients infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Coagulase-negative Staphylococci can infect immunocompromised patients. Linezolid resistance among Staphylococcus epidermidis is one of the most critical issues. In 2019, 185 SARS-CoV-2-positive patients who were admitted to North Khorasan Province Hospital (Bojnurd, Iran), were investigated. Patients having positive SARS-CoV-2 reverse transcriptase real-time polymerase chain reaction (RT-PCR) test results, who had a history of intubation, mechanical ventilation, and were hospitalized for more than 48 hours were included. After microbiological evaluation of pulmonary samples, taken from intubated patients with clinical manifestation of pneumonia, co-infections were found in 11/185 patients (5.94%) with S. epidermidis, Staphylococcus aureus, and Acinetobacter baumani, respectively. Remarkably, seven out of nine S. epidermidis isolates were linezolid resistant. Selected isolates were characterized using antimicrobial resistance patterns and molecular methods, such as Staphylococcal cassette chromosome mec (SCCmec) typing, and gene detection for ica, methicillin resistance (mecA), vancomycin resistance (vanA), and chloramphenicol-florfenicol resistance (cfr) genes. All of the isolates were resistant to methicillin, and seven isolates were resistant to linezolid. Nine out of 11 isolated belonged to the SCCmec I, while two belonged to the SCCmec IV. It should be noted that all patients had the underlying disease, and six patients had already passed away. The increasing linezolid resistance in bacterial strains becomes a real threat to patients, and monitoring such infections, in conjunction with surveillance and infection prevention programs, is very critical for reducing the number of linezolid-resistant Staphylococcal strains. A preprint of this study was published at https://europepmc.org/ article/ppr/ppr417742. [ABSTRACT FROM AUTHOR]

Background: Carbapenemase-resistant Enterobacteriaceae is a major threat to public health. These microorganisms are resistant to all types of beta-lactam antibiotics. Methods: This cross-sectional study was conducted on 51 Enterobacteriaceae isolates from clinical samples in Sina Hospital and Tehran Heart Center in Iran from 2016 to 2018. Antibiotic susceptibility test was performed by disk diffusion method. Carbapenem-resistant isolates were identified by the Modified Hodge Test (MHT) and Polymerase Chain Reaction (PCR) for surveying the presence of VIM, NDM, IMMP, and OXA-48 genes. Results: Out of 51 clinical samples, 38 isolates were positive for both MHT and PCR tests, and 5 isolates were negative in both tests. The results of both tests are similar in 84.3% of the isolates. Conclusion: The MHT is an appropriate and easy method for approving carbapenemase production. Also, a laboratory can detect the carbapenemase production by identification of the KPC genes. [ABSTRACT FROM AUTHOR]

Haemonchosis is one of the most important parasitic diseases of the gastrointestinal tract of small ruminants in different parts of Iran and worldwide. While the disease poses major economic problems in the livestock industry, there are many reports on parasites' resistance to benzimidazoles necessitating to study of the level of this drug resistance in pathogens. The aim of this study was to evaluate the drug resistance of Haemonchus contortus to benzimidazole using molecular method in sheep from the North region of Iran. In this study, the resistance to benzimidazole was investigated using the PCR-RFLP method in the nematode Haemonchus contortus from sheep slaughtered in the northern region of Iran (Gilan and Mazandaran provinces). The samples examined in this study were evaluated between April 2020 and September 2021 from a total of 2400 sheep by determining the age groups of <2 years, 2>4 years, and >4 years. Three hundred Haemonchus contortus nematodes were randomly selected and investigated by means of PCR-RFLP and using TaaI endonuclease enzyme (SNP) in the beta-tubulin gene, responsible for drug resistance of Haemonchus contortus to benzimidazole. Haemonchus contortus was found in 66.8% and 60.5% of sheep in Gilan and Mazandaran. The results of the study showed that the drug sensitivity rate was 24% (72/300), the drug resistance rate was 54% (162/300) and 22% (66/300) of the samples had both resistant and sensitive alleles. Presented data showed a high level of prevalence of drug resistance in the nematode Haemonchus contortus in sheep in the northern region of Iran, which requires special attention to control the development of this resistance and the epidemic of haemonchosis in ruminants. [ABSTRACT FROM AUTHOR]

Background: Antibiotics are used to treat and prevent oral infections. Clindamycin and penicillin are widely used drugs in this field. Poor use of antibacterial agents causes the emergence of antibiotic-resistant bacteria. Objectives: The present study examined and compared the frequency distribution of resistance of streptococci isolated from the root surface of extracted teeth to penicillin V and clindamycin. This study was conducted in 2021 in Yazd, Iran. Methods: Thiswas an analytical cross-sectional study performed in vitro. The sampleswere taken fromthe root surfaces of 50 teeth immediately after extraction and transferred to the laboratory in a transfermedium. After cultivation, isolation, and identification, the antibiotic resistance of isolates wasmeasured by the E-testmethod. The data were analyzed using SPSS software (version 23). Results: Streptococci spp. were isolated from 46 samples (92%) without environmental contamination. The minimum inhibitory concentration (MIC) 50 andMIC 90 for penicillin V were 0.5 µg/mL and 1 µg/mL, respectively, and for clindamycin, 0.125 µg/mL and 0.19 µg/mL, respectively, which was significantly (P = 0.0001) lower for clindamycin. Intermediate sensitivity to penicillin V was 95.6%, and resistance to clindamycin was 21.8%. Conclusions: It seems that except inlimitedcaseswhere there is resistance to clindamycin, this antibiotic is amore effectivedrug to control the bacteria in themouth. However, in some cases, aerobic isolates showed intermediate sensitivity to penicillin V; instead, resistance to clindamycin was observed. [ABSTRACT FROM AUTHOR]

Purpose: Investigating the genetic variation in thioredoxin reductase (TrxR) and nitroreductase (NR) genes in both treatment-resistant and -sensitive Giardia duodenalis isolates can provide valuable information in identifying potential markers of resistance to metronidazole. The rapid increase in metronidazole treatment failures suggests the presence of genetic resistance mechanisms. By analyzing these genes, researchers can gain insights into the efficacy of metronidazole against G. duodenalis and potentially develop alternative treatment strategies. In this regard, four G. duodenalis isolates (two clinically sensitive and two clinically resistant to metronidazole) were collected from various hospitals of Shiraz, southwestern Iran. Methods: Parasitological methods including sucrose flotation and microscopy were employed for the primary confirmation of G. duodenalis cysts in stool samples. Microscopy-positive samples were approved by SSU-PCR amplification of the parasite DNA. All four positive G. duodenalis specimens at SSU-PCR were afterward analyzed utilizing designed primers based on important metronidazole metabolism genes including TrxR, NR1, and NR2. Results: Unlike TrxR gene, the results of NR1 and NR2 genes showed that there are non-synonymous variations between sequences of treatment-sensitive and -resistant samples compared to reference sequences. Furthermore, the outcomes of molecular docking revealed that there is an interaction between the protein sequence and spatial shape of treatment-resistant samples and metronidazole in the position of serine amino acid based on the NR1 gene. Conclusion: This issue can be one of the possible factors involved in the resistance of Giardia parasites to metronidazole. To reach more accurate results, a large sample size along with simulation and advanced molecular dynamics investigations are needed. [ABSTRACT FROM AUTHOR]

Introduction: Tuberculosis (TB) remains a serious public health problem worldwide. Drug-resistant TB is considered a major and growing global threat. Despite the great variety of described mutations in Mycobacterium tuberculosis (MTB) resistance genes, the mechanisms of drug resistance are still controversial. Recently, a report on the role of efflux pump genes in drug resistance added to this complexity. Therefore, a thorough understanding of efflux pump genes in drug-resistant TB clinical isolates is needed. Methodology: We performed molecular analysis of the efflux pump gene (Rv1258c) in 33 drug-resistant and 20 drug-sensitive clinical MTB isolates by sequencing the amplicons' targets in both the forward and reverse directions. Results: A novel mutation of the Rv1258c gene was identified at G442A (Ala148Thr) in rifampicin mono-resistant clinical strain, as compared to the H37Rv reference strain. In addition, a cytosine nucleotide insertion was found between the positions 580 and 581 (denominated Tap580) in two drug-sensitive strains at identical gene positions. Conclusions: These results indicated the possibility of mutation in the efflux pump genes and the important role of Tap efflux pump genes in drug-resistant MTB isolates. However, further research is required to determine the direct association of these mutations with resistant MTB. [ABSTRACT FROM AUTHOR]

Background: There is no systematic review on the prevalence of HIV drug resistance (HIVDR) in Iran. We aimed to estimate the prevalence of HIVDR among people living with HIV (PLHIV) in Iran. We assessed HIVDR prevalence in antiretroviral therapy (ART) naïve PLHIV (i.e., those without a history of ART) and PLHIV receiving ART. Method: We systematically searched Scopus, PubMed, Web of Science, Embase, Iranian databases (Iranian Medical Research Information System, Magiran, and Scientific Information Database), the references of studies, and Google Scholar until March 2023. A random-effects model was used to calculate a point estimate and 95% confidence interval (95% CI) for the prevalence of HIVDR in PLHIV. Results: Among 461 potential publications, 22 studies were included in the meta-analysis. The pooled prevalence of acquired HIVDR in PLHIV receiving ART was 34% (95% CI: 19, 50) for nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs), 27% (95% CI: 15, 41) for non-nucleoside reverse transcriptase inhibitors (NNRTIs), and 9% (95% CI: 3, 18) for protease inhibitors (PIs). The pooled prevalence of acquired HIVDR in treatment failure PLHIV was 50% (95% CI: 31, 69) for NRTIs, 49% (95% CI: 29, 69) for NNRTIs, 11% (95% CI: 2, 24) for PIs, and 1% (95% CI: 0, 4) for integrase inhibitors (INIs). The pooled prevalence of transmitted HIVDR in ART-naïve people was 3% (95% CI; 1, 6) for NRTIs, 5% (95% CI: 2, 9) for NNRTIs, and 0 for PIs and INIs. Conclusion: The prevalence of HIVDR was relatively high in both ART-naïve PLHIV and those receiving ART. Without universal pretreatment HIVDR testing and more frequent routine HIV viral load testing among PLHIV who are on ART, the HIVDR prevalence might increase in PLHIV in Iran. [ABSTRACT FROM AUTHOR]

Background: The prevalence of drug-resistant Staphylococcus aureus is increasing alarmingly, limiting treatment options. Objectives: This study was conducted to investigate the minimum inhibitory concentration (MIC) of glycopeptides against multidrug-resistant (MDR) and extensively drug-resistant (XDR) S. aureus isolates from patients with skin infections. Methods: In this study, S. aureus isolates were collected from outpatients with skin infections (n = 250) during 2019 - 2022. The isolates were identified using routine microbiological and biochemical tests. Susceptibility to ten categories of antibacterial agents was assessed using the Kirby-Bauer method according to the Clinical and Laboratory Standards Institute M100 guidelines (2021). The MIC of glycopeptides was determined using the broth microdilution test. Results: Among methicillin-resistant S. aureus isolates (40.8%), the majority were from patients with impetigo (53.92%). The highest resistance rate was observed against penicillin (79.41%) and doxycycline (73.52%). Linezolid showed significant inhibitory properties against XDR (91%) and MDR (97%) S. aureus isolates (P = 0.01). The MIC of oritavancin that inhibited the growth of 90% of the MDR isolates (MIC90) was 2 μg/mL, which was eight times less than that of vancomycin (MIC90 = 16 μg/mL) and 16 times lower than that of teicoplanin (MIC90 = 32 μg/mL) in a manner that 91% of MDR isolates from impetigo were eliminated at concentrations 2 μg/mL. Oritavancin inhibited the growth of 54.5% of XDR isolates at MIC concentrations of >8 μg/mL. Conclusions: Considering the strong antibacterial activity of linezolid against MDR S. aureus isolates, this antibiotic can effectively treat skin infections caused by S. aureus and prevent the development of resistance to other antibiotics. In addition, considering the great inhibitory properties of oritavancin against MDR S. aureus strains, the efficacy of this agent for treating skin infections, particularly impetigo, should be investigated. [ABSTRACT FROM AUTHOR]

Background: Gastroenteritis refers to an infection in the stomach and small intestine that may be caused by bacteria, viruses, and other pathogenic agents. Most strains of Escherichia coli (E. coli) in the gastrointestinal system have shared a symbiotic relationship with humans, but some serotypes are pathogenic. This study aimed to identify E. coli pathotypes isolated from stool samples and determine the antibiotic resistance profiles of these pathotypes in the west of Iran. Methods: The study was conducted on 106 samples of diarrheal feces which were sent to Imam Reza laboratory. First E. coli was detected and then the DNA was extracted. Next, the antibiotic sensitivity test was performed by the disk diffusion method. The E. coli pathotypes were qualitatively detected using the Amplisense Escherichioses- FRT PCR kit after DNA extraction from E. coli isolated in the stool sample. Results: In this study, out of 106 E. coli-positive samples, pathogenic E. coli were detected in 62 samples including 5 samples (8.1%) which only contained the EPEC pathotype, 10 samples (16.1%) contained only the EAEC pathotype, and 12 samples (19.4%) had only the EHEC pathotype. ETEC and EIEC were not isolated from any of the samples. The sensitivity to Meropenem (97%) and Gentamicin (96.2%) showed the highest frequency among the samples. The highest level of resistance was related to Amoxicillin (93.4%) and Ampicillin (78%). Conclusions: The epidemiological results show that the predominant pathotype among all isolates is EHEC and most antibiotic resistances were related to Amoxicillin and Ampicillin. Finally, a comprehensive molecular diagnosis of E. coli pathotypes, investigation of their incidence, and antibiogram profiles will help to determine better diagnostic and therapeutic measures for managing diarrheal diseases. [ABSTRACT FROM AUTHOR]

Objective(s): Difficult-to-treat Streptococcus agalactiae infections are increasingly described in patients with urinary tract infections (UTIs). This occurrence could be due to the production of virulence determinants. This study aimed to characterize the molecular features of S. agalactiae responsible for UTIs. Materials and Methods: In this cross-sectional study, 70 S. agalactiae isolated from UTIs were examined. Antibiotic susceptibility testing was performed using the disk diffusion method. All S. agalactiae isolates were confirmed by atr and dltS PCR assays. Virulence, alpha protein-like, and pilus island genes were detected by PCR. Isolates were characterized using the multilocus sequence typing method. Results: Multidrug resistance was observed in 80% of isolates. Five virulence profiles were detected, wherein cylE, lmb, bca, rib (35.7%), cylE, lmb, alp3 (27.1%), and cylE, lmb, bac, rib, alp2 (21.4%) were the most frequent detected profiles. S. agalactiae was isolated and categorized within three clonal complexes (CCs) including CC22 (40%), CC17 (25.7%), and CC23 (20%). The main sequence types (STs) found were ST22 (27.1%), ST23 (17.1%), ST17 (12.9%), ST31 (8.7%), ST40 (8.7%), ST74 (7.1%), ST48 (4.3%), ST890 (4.3%), ST189 (2.8%), ST38 (2.8%), ST52 (2.8%), and ST155 (1.4%). ST74 and ST38 were reported for the first time in Tehran-Iran. Conclusion: This study highlights the predominance of the CC22 lineage among S. agalactiae strains isolated from UTIs in Tehran, Iran, and highlights the significant penetration of this lineage into hospitals. MDR patterns among these strains appear to be becoming a major concern in the management of infections. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Candida albicans (C. albicans) is recognized as the most common opportunistic pathogen in patients with an impaired immune system, and due to the frequent use of antifungal medicine, a variety of drug-resistant species are developing. Probiotics are a part of the human microbiome and natural competitors of Candida by producing lactic acid, low pH, and other secreted metabolites. The role of probiotics in preventing fungal infections has always been discussed. Purpose: This study aimed to investigate the antifungal effect of Lactobacillus casei (L. casei) on fluconazole- and amphotericin B-resistant C. albicans species isolated from the oral cavity of acute myeloid leukemia patients. Materials and Method: In this experimental study, eight strains of fluconazole- and amphotericin B-resistant C. albicans were used. The antifungal effects of probiotic L. casei and nystatin were measured by the co-aggregation method 1, 2, and 4 h after beginning the study. After each hour of exposure, C. albicans and L. casei colonies were counted. Results: L. casei had a significant ability to aggregate with both fluconazole- and amphotericin B-resistant C. albicans in all designated intervals, which increased with time. In the first hour of the study, no significant difference was observed between the effects of L. casei on the two drug-resistant strains. However, as time passed, it had a more significant antifungal effect on fluconazole, compared to amphotericin B resistant species (p Value<0.001). Cell counts showed that the number of fungal cells decreased significantly as time passed (p< 0.001). Conclusion: L. casei had a significant ability to aggregate with both drug-resistant C. albicans species and showed higher antifungal activity on fluconazole-resistant than amphotericin B-resistant species. [ABSTRACT FROM AUTHOR]

The prevalence of Streptococcus agalactiae infections in adult populations is increasing. The current study aimed to characterize the genetic features of S. agalactiae strains responsible for different infections. A cross-sectional study was performed on 65 S. agalactiae strains (30 invasive and 35 noninvasive) isolated from non-pregnant women. All S. agalactiae isolates were confirmed by atr and dltS PCR assays. Antibiotic susceptibility patterns were determined using the disk diffusion method. Biofilm production was investigated by microtiter plate assay. PCR was done to detect resistance determinants. Isolates were characterized using the multilocus sequence typing (MLST) method. cMLSB, iMLSB, and M phenotypes accounted for 47.7%, 30.8%, and 6.2%, respectively. MDR was detected in 15.4% of noninvasive and 44.6% of invasive isolates. MtP assay indicated that 80% of isolates were biofilm producers. Biofilm formation was common among noninvasive compared with invasive strains (94.3% versus 66.7%). tet (M) (46.2%) and erm (B) (69.2%) were the most prevalent tetracycline and macrolide-resistance genes. The most prevalent serotype was type III (50.8%), followed by Ia (18.4%), II (15.4%), V (12.3%), and IV (3.1%). The frequency of serotype III among biofilm producer strains (81.8%) was found to be significantly higher than that of non-producer isolates (18.2%) (P < 0.05). S. agalactiae was resolved within four clonal complexes, including CC19 (46.2%; in both invasive and noninvasive), followed by CC23 (30.8%; only noninvasive isolates), CC1 (15.4%; only noninvasive isolates) and CC17 (7.6%; only invasive isolates). The main sequence types (STs) found were ST19 (27.7%), ST17 (7.7%), ST27 (6.2%), and ST28 (4.6%) linked with invasive infections and ST23 (18.4%), ST933 (12.3%), ST644 (9.2%), ST19 (7.7%), ST1 (6.2%) found in noninvasive infections. The high prevalence of CC19 and CC23 clones among S. agalactiae strains reflects the emergence of these lineages as successful clones in Iran. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to evaluate the antibiotic resistance patterns and prevalence of carbapenemase genes in Klebsiella pneumoniae isolates in different clinical samples from Tabriz city, northwestern Iran. Results: This cross-sectional study was conducted in the Department of Microbiology, Islamic Azad University, Ahar Branch, Iran, in 2020. K. pneumoniae isolates were collected from different clinical samples, including blood, wounds, sputum, and urine. The isolates were identified using a series of standard bacteriological tests. Antibiotic resistance was determined by the disc diffusion method. The presence of blaVIM, blaNDM, blaKPC, blaOXA, and blaIMP genes were screened by polymerase chain reaction (PCR). A total of 100 non-duplicated K. pneumoniae isolates were collected from 57 urine samples, 27 blood samples, 13 wound samples, and 3 sputum samples. Overall, 70.0% of the samples were from inpatients, while 30.0% were from outpatients. The most resistance rate was related to ampicillin (94.0%), while the lowest resistance rate was related to imipenem (18.0%) and meropenem (20.0%). Overall, 25.0% of the isolates were carbapenem-resistant, of which 13.0% were resistant to both imipenem and meropenem. The PCR showed the total prevalence of 23.0% for carbapenemase genes, including 18.0% for blaKPC, 3.0% for blaVIM, 1.0% for blaIMP, and 1.0% for blaOXA gene. The blaNDM gene was not detected in any isolate. The prevalence of carbapenemase-producing K. pneumoniae isolates was relatively lower in northwestern Iran than in other regions of the country. However, special attention should be paid to the proper use of antibiotics, particularly carbapenems, to prevent further spread of antibiotic resistance and its related genes. [ABSTRACT FROM AUTHOR]

Background: Group B Streptococcus (GBS) can cause serious infections in neonates and pregnant women. GBS may cause urinary tract infections (UTIs). However, molecular epidemiology of such infections is rarely reported. The present study aimed to determine drug resistance patterns and molecular serotyping of GBS isolates in a population of pregnant Iranian women with UTIs. Methods: A cross-sectional study was conducted during the first half of 2021 in the Department of Biology, East Tehran Branch, Islamic Azad University (Tehran, Iran). Sixty GBS strains isolated from the urine and placenta samples of pregnant women with UTIs were evaluated. The women were aged 19-46 years old at 35 to 37 weeks of gestation. The molecular serotype of GBS isolates was determined using a multiplex polymerase chain reaction, and the disc diffusion method was used to determine the antibiotic susceptibility pattern of isolates for different antibiotics. The association of the GBS serotype with the phenotype of antibiotic resistance was statistically analyzed using SPSS software (version 22.0) with a Chi square test and Cramer's V test. P<0.05 was considered statistically significant. Results: GBS capsular serotype II was most prevalent (66.7%) followed by serotypes Ib (21.7%), Ia (3.3%), and III (1.7%). The prevalence of non-typeable isolates was significantly low (6.6%). Of the 60 GBS isolates, 18.3% were resistant to penicillin, 81.6% to ampicillin, 23.3% to clindamycin, and 30% to vancomycin; indicating the need for treatment alternatives. Conclusion: Region-specific information on antibiotic resistance and molecular characteristics of GBS is essential for epidemiological investigations, effective treatment, and vaccine development. [ABSTRACT FROM AUTHOR]

Increased drug resistance has reduced efficiency of chemotherapic drugs such as Doxorubicin (Dox). Scrophularia amplexicaulis (Scr) is one of the most important medicinal plants in Iran that has anti‐cancer activity. The aim of this study was to investigate a novel approach to enhance therapeutic efficacy of Dox (as a chemotherapeutic agent) by co‐administration of Scr (as a bioactive herbal compound) in gastric cancer treatment. In the present study, effects of Dox, Scr, and their combinations (Scr‐Dox) were evaluated on viability and proliferation of two gastric cancer cell lines (AGS and MKN28). Moreover, morphological changes, invasion, migration, colony formation, and apoptosis rate in the treated cancer cells were evaluated. Expression of BAX, BCL2, SAMC, SURVIVIN, CASP9, P53, MMP9, and MMP2 in the treated cancer cells and untreated controls were evaluated by Real‐Time PCR method. Treatments of cancer cells by Scr, Dox, and Scr‐Dox significantly decreased proliferation, invasion, migration, and colony formation of gastric cancer cells. Treatments of cancer cells by Scr, Dox, and Scr‐Dox significantly increased apoptosis rate as well as decreased cells mobility through modification of apoptosis‐ and metastasis‐related genes expression. However, anti‐cancer activity of Scr‐Dox combination was significantly more than Scr and Dox treatments alone. In general, we demonstrated that Scr‐Dox combination therapy exerts more profound anti‐cancer effects on AGS and MKN28 cell lines than Scr and Dox monotherapy. [ABSTRACT FROM AUTHOR]

Background and Objectives: The study aimed to investigate the distribution of genes encoding integrons, extended spectrum beta-lactamase (ESBL) in E. coli isolated from UTIs, as well as the genetic diversity among the isolates. Materials and Methods: E. coli isolates were recovered from the patients with UTI in Kerman Iran. Antibiotic susceptibility was done according to CLSI guidelines. The presence of ESBL genes and integrons was evaluated using PCR. PCR and sequencing were applied for the evaluation of cassette content of integrons. Genotyping of the isolates was performed by multiple-locus variable-number tandem repeat analysis (MLVA). Results: Imipenem was the most effective antibiotic, while the highest resistance was observed to streptomycin. In total 40.2% of isolates were ESBL producers. Of 69 integron-positive isolates, 59 only had class I integrons, 4 only had class II integrons and 6 had both types. The most common gene cassette found within class I integrons was dfrA17-aadA5 (n=27). The E. coli isolates were divided into 16 MLVA clusters. Conclusion: The current study demonstrated the simultaneous presence of class I integrons and ESBLs involved in the resistance of UPEC isolates to antibacterial agents. Our finding also revealed that the E. coli isolates belonged to diverse clones. [ABSTRACT FROM AUTHOR]

Increase in antibiotic resistance in Staphylococcus aureus isolated from ear infection is a serious public health problem. The objective of this investigation was to determine the antibacterial resistance profile and genetic variability of the S. aureus isolated from adult patients with otitis externa (OE) and otitis media (OM) infections, Tehran- Iran. The disk diffusion was employed to detect the susceptibility of 45 S. aureus strains. Biofilm production was evaluated by microtiter plate assay. Genetic diversity of the isolates was determined by staphylococcal cassette SCC mec , spa , and MLST techniques. Resistance to mupirocin and vancomycin were identified in 40 and 2.2% of isolates. Out of the 45 S. aureus isolates, 41 (91.2%) strains were considered as positive biofilm strains at different levels. According to our results, S. aureus isolated from OM (44.4%, 20/45) were including CC8/ST239-SCC mec III corresponded to spa types t860, t030, t037, t234, t421 (70%, 14/20) and CC/ST30-SCC mec IV corresponded to spa types t605 and t019 (30%, 6/20) while S. aureus isolated from OE (55.6%, 25/45) were including CC/ST30-SCC mec IV corresponded to spa types t605, t345 and t1130 (52%, 13/25), CC/ST22-SCC mec IV corresponded to spa type t790 (20%, 5/25), CC8/ST8-SCC mec IV corresponded to spa type t008 (16%, 4/25), and CC/ST45-SCC mec IV corresponded to spa types t004 and t038 (12%, 3/25). This study highlighted genetic variability and strong biofilm formation ability among our isolates revealing its crucial role in enhancing the resistance of this bacteria to drugs. Thus, it is necessary to continue the epidemiological analysis to improve the control of ear infections related to S. aureus. [ABSTRACT FROM AUTHOR]

Background: Infectious diseases are still one of the leading causes of morbidity and mortality in resource-limited settings. Serious infection caused mostly by gram-negative pathogens causes significant morbidity. According to the Centers for Disease Control and Prevention, antimicrobial resistance kills over 700,000 people worldwide. Antibiotic resistance is on the rise, and as a consequence, serious public health issues are arising. The present study investigated isolated clinical samples from Yasuj teaching hospitals to determine the antimicrobial resistance profile to various antibiotics. Materials and methods: Microbial isolates regarding cultures from urine, blood, wound, abdominal tap, throat, stool, cerebrospinal fluid, endotracheal tube, sputum, skin lesion, nasal, and mouth secretion were collected from patients admitted to hospitals affiliated with Yasuj teaching hospitals. Antibiotic susceptibility profiles were determined by using the Kirby-Bauer disc diffusion method. Data were tabulated and analyzed with SPSS version 26.0. Results: A total of 783 samples were evaluated in our study, with an average of 30.6 years and 54.5% female patients. Most of the bacterial isolates were gram-negative (64.2%). The majority of cultures were Escherichia coli (49.9%), mainly among urine samples (64.2%). The frequency distribution of norfloxacin antibiotic resistance was more common in internal medicine (66.7%), infectious (63.6%), and emergency wards (58.8%). The frequency distribution of penicillin antibiotic resistance was statistically significant in different wards. All cases of oxacillin were resistant. Conclusion: Our data showed a high level of antibiotic resistance among bacterial isolates in our center. Considering widespread empirical antibiotic therapy in Iran, the rate of increasing resistance to common antibiotics prescribed for ambulatory and hospitalized patients is concerning. We recommend providing more strict guidelines and policies to control the overuse and overprescription of antimicrobials by health policy-making organizations. [ABSTRACT FROM AUTHOR]

Objective: Antiplatelet drugs, such as Aspirin and Clopidogrel (Plavix) are effective in the primary prevention of thromboembolic events. They are commonly used to reduce the risk of recurrence of thromboembolism. The body's hemostatic system responds differently to these drugs in different people. Resistance testing for aspirin and Clopidogrel is now recommended before starting antiplatelet therapy. Methods: A systematic literature search was performed on May 12, 2021, using the medical search engines PubMed, Scopus, and Web of Science, and the local databases SID and Magiran. After data extraction, a meta-analysis was performed using Comprehensive Meta-Analysis (CMA2) software. The I2 statistic was used to measure heterogeneity between estimates. Results: Among the 949 papers, Clopidogrel resistance was assessed in 136 patients and Aspirin resistance in 400 patients. The prevalence of Aspirin resistance was found to be 52.1% and the prevalence of Clopidogrel resistance was found to be 20.5%. Conclusion: It seems that in Iran, the issue of Aspirin and Clopidogrel resistance is suboptimally addressed. This pattern could also occur in other developing countries in the Middle East region. [ABSTRACT FROM AUTHOR]

Carbapenemases-producing K. pneumoniae are challenging antimicrobial therapy of hospitalised patients, which is further complicated by colistin resistance. The aim of this study was to investigate the molecular epidemiological insights into carbapenemases-producing and colistin-resistant clinical K. pneumoniaeA total of 162 colistin resistant clinical strains of K. pneumoniae were collected during 2017–2019. Antimicrobial susceptibility and the colistin minimum inhibitory concentration were determined. Using PCR assay, the prevalence of resistance-associated genes including blaKPC, blaIMP, blaVIM, blaOXA-48, blaNDM-1 and mcr-1 to -9 was examined. Additionally, a PCR assay was used to examine the mgrB gene in colistin-resistant bacteria. 94.4% of the tested strains were resistant to imipenem and 96.3% were resistant to meropenem. Colistin resistance (MIC > 4 µg/L) was observed in 161 isolates (99.4%) by Colistin Broth Disk Elution method. The KPC enzyme was the most common carbapenemase and was identified in 95 strains (58.6%), followed by the IMP, VIM and OXA-48 detected in 47 (29%), 23 (14.2%) and 12 (7.4%) isolates, respectively. However, no NDM-1 gene was detected. Additionally, none of the studied isolates harbored mcr variants, while mgrB gene was observed in 152 (92.6%) isolates. Colistin resistance of K. pneumoniae isolates may be associated with mgrB gene mutation. To stop the spread of resistant K. pneumoniae, surveillance must be improved, infection prevention protocols must be followed, and antibiotic stewardship must be practised. [ABSTRACT FROM AUTHOR]

Background: Human Immunodeficiency Virus (HIV) has claimed the lives of millions of people during the past decades. While several antiretroviral drugs like Integrase Strand Transfer Inhibitors (INSTIs) have been introduced to control HIV, Transmitted Drug Resistance (TDR) in HIV genome caused failure in treatment. This study aimed to investigate TDR and natural occurring mutations (NOPs) in HIV integrase gene in Iranian HIV patients. Methods: In this cross-sectional study, blood samples of 30 HIV-positive patients who had never taken integrase inhibitors were considered for CD4 T cell count, RT real-time PCR, and, Nested PCR. The sequencing results were analyzed by CLC sequence viewer software and Stanford University HIV Drug Resistance Database. Results: In all samples, nine NOPs with a high prevalence were found; however, we did not find any drug resistance mutations, except for a mutation in one sample, which showed a low resistance level. Subtype A1 was dominant in all samples. Conclusion: Based on the findings and compared to our previous study, all patients were sustainable to main integrase inhibitors, including bictegravir, raltegravir, bicte-gravir, elvitegravir and dolutegravir. It seems the resistant mutation pattern attributed to integrase inhibitors was not diffent among studied patients; hence, the prescription of such inhibitors helps physicians to control HIV infection in Iranian HIV-infected patients. [ABSTRACT FROM AUTHOR]

Background: Escherichia coli is an important cause of urinary tract, bloodstream, and surgical site infections. Objectives: We investigated the organism's antibiotic susceptibility in hospitalized patients under different clinical conditions. Methods: This prospective study was conducted in three referral hospitals located in Isfahan, Iran. Different clinical samples were tested using standard routine microbiological methods to identify E. coli strains and determine their antibiotic susceptibility patterns by the disk diffusion method according to CLSI recommendations. After conducting a clinical investigation, contaminated samples were excluded, and the hospital or community source and infection site were identified. Data on antibiotic susceptibility testing were extracted using WHONET software. Data analysis was then conducted using SPSS Statistics version 18.0. Results: Of 1248 E. coli isolates, 71.9% were from urine, 15.1% from blood, and 7.8% from skin and soft tissue samples. High susceptibility was observed to Imipenem (98%), Meropenem (98.0%), and Amikacin (94.6%); intermediate sensitivity to Gentamicin (68.6%) and Cefepime (51.9%); and low susceptibility to Ceftazidime (46.8%), Ceftriaxone (41.3%), Ciprofloxacin (39.5%), Cefotaxime (39.3%), and Trimethoprim-sulfamethoxazole (32.4%). Conclusions: Antibiotics, including Imipenem, Meropenem, or Amikacin, would be beneficial in the empiric therapy of severe infections where E. coli is the main cause. [ABSTRACT FROM AUTHOR]

Background and Objectives: The immediate emergence of resistant bacteria poses an increasingly growing problem to human society and the increasing prevalence of antibiotic resistance in Escherichia coli strains is one of the most important health problems. This study aimed to review the molecular epidemiology of drug resistance among clinical isolates of E. coli in north-west portion of Iran Azerbaijan. Materials and Methods: A complete of 219 clinical isolates of E. coli had been collected from the various clinical samples. The disk diffusion and agar dilution assays were used to determine antimicrobial susceptibility. The presence of antibiotics resistance genes was carried out by the PCR method. Results: The highest susceptibility was shown to imipenem (3%) and fosfomycin (3%), and the most antibiotic resistance was presented to ampicillin (99%). The highest frequent ESBL gene among isolates was bla CTXM-15 in 70% followed by bla CMY-2 in 67%, and bla TEM-1 in 46%. The most common fluoroquinolone (FQ) resistance genes were oqxB (34%), followed by oqxA (25%), and qnrB (18%). The frequency of tetracycline resistance genes (tetA, tetB, tetC, and tetD) were detected in 24.8%, 31.6%, 1.8%, and 4.2%, respectively. The highest frequent genes to fosfomycin were fosA 10%, fosA3 30%, fosC 40%, and fosX 20%. The dominant founded aminoglycosides resistant genes were armA (12.96%) and npmA (4.93%). Conclusion: The prevalence of antibiotics resistance in the tested E. coli isolates was high in Azerbaijan, Iran and these findings showed that E. coli is one of the major drug-resistant pathogens. [ABSTRACT FROM AUTHOR]

Mycobacterium fortuitum is a clinically important species among nontuberculous mycobacteria (NTM). Treatment of diseases caused by NTM is challenging. The aim of this study was identification of drug susceptibility and detection of mutations in erm(39) related to clarithromycin resistance and in rrl related to linezolid resistance in clinical isolates of M. fortuitum in Iran. In the study, 328 clinical NTM isolates were subjected to identification based on rpoB and 15% of isolates were assigned to M. fortuitum. Minimum inhibitory concentration for clarithromycin and linezolid was determined by E-test. Altogether 64% of M. fortuitum isolates showed resistanc to clarithromycin and 18% of M. fortuitum isolates showed resistance to linezolid. PCR and DNA sequencing were performed in erm(39) and in rrl genes for detection of mutations related to clarithromycin and linezolid resistance, respectively. Sequencing analysis revealed (84.37%) single nucleotide polymorphisms in the erm(39). A total 55.55% of M. fortuitum isolates harbored an A→G, 14.81% harbored an C→A, 29.62% harbored an G→T mutation in erm(39) at position 124, 135, 275. Seven strains harbored point mutation in the rrl gene either at T2131C or at A2358G. Our findings showed M. fortuitum isolates have become a serious problem with high-level antibiotic resistance. The existence of drug resistance to clarithromycin and linezolid indicates more attention to the study of drug resistance in M. fortuitum. [ABSTRACT FROM AUTHOR]

Background: Urinary tract infection (UTI) is one of the most prevalent infectious diseases with worldwide health threatening. Antimicrobial resistant strains of Escherichia coli (E. coli) are a common cause of UTI which were identified as a treatment challenge. This study aimed to assay the prevalence of common β-lactam resistance genes including blaTEM, blaSHV, blaCTX-M and blaCMY and phenotypic resistance to commonly used β-lactam and fluoroquinolone antibiotics in UTIs. These factors were evaluated in various phylogenetic groups (phylotypes) of E. coli isolates. Real-time PCR was applied to detect β-lactam resistance genes and conventional PCR was used to determine the phylotypes. Phenotypic resistance against β-lactams (ceftazidime, cefotaxime, aztreonam and ceftriaxone) and fluoroquinolones (ciprofloxacin) were identified by the disc diffusion technique. The ability of extended spectrum β-lactamases (ESBLs) production in E. coli isolates was detected using the combined disc diffusion method. Results: The prevalence of resistance genes were 89.6% for blaTEM, 44.3% for blaCTX-M, 6.6% for blaSHV and 0.9% for blaCMY. The two high prevalent phylotypes were B2 (29.2%) and D (17.9%) followed by E (14.1%), F (9.4%), C (6.6%) and 10.3% of isolates were unknown in phylotyping. Disc diffusion results showed high prevalence of antibiotic resistance to cefotaxime (88.6%), aztreonam (83%), ceftireaxon (77.3%), ceftazidime (76.4%) and ciprofloxacin (55.6%). Totally, 52.8% of isolates were found as phenotypical ESBL-producers. Conclusions: This study's results confirmed an explosion of antibiotic resistance amongst E. coli isolates from UTI against β-lactams and fluoroquinolones. Findings explain the necessity of deep changes in quantity and quality of drug resistance diagnosis and antibiotic therapy strategies. More studies are suggested to better and confident evaluations. [ABSTRACT FROM AUTHOR]

Background: The spread of Plasmodium vivax strains resistant to chloroquine (CQ) has posed a challenge to control strategies aimed at eliminating malaria. Molecular analysis of candidate resistance markers is very important for monitoring the P. vivax resistance to CQ in different endemic regions. In the present study, the multidrug resistance 1 (pvmdr1) gene, a possible marker for CQ resistance in P. vivax, was evaluated by molecular methods. Methods: A simple PCR–RFLP method was developed for mutation analysis in pvmdr1 gene. A number of 120 blood spots were obtained from patients with P. vivax mono-infection in 2021. All of the samples were collected from Pakistani patients who travelled to Iran. Results: None of the samples had any mutation at codon 976 of pvmdr1, while the 1076 mutation was detected in 96.2% of the examined isolates. Only two pvmdr1 haplotypes were identified, including the single mutant (Y976/1076L) as the most prevalent haplotype (with 96.2% frequency) and the wild type (Y976/F1076; with 3.8% frequency). Conclusions: In this study, the major CQ resistance-mediating mutation and multiple mutant haplotypes of the pvmdr1 gene was not detected. However, continuous monitoring of drug resistance markers and close supervision of the efficacy of CQ is essential to detect the potential emergence of CQ-resistant P. vivax isolates in Iran. This data is important for performing future epidemiological surveillance to monitor CQ resistance in this endemic area and the bordering regions. [ABSTRACT FROM AUTHOR]

Background: Circulating microRNAs (miRNAs) can help to predict the chemotherapy response in breast cancer with promising results. The aim of the present study was to investigate the relationships between the miR-199a, miR-663a, and miR-663b expression and chemotherapy response in metastatic breast cancer patients. Methods: This study is a case-control study performed at Yasuj University of Medical Sciences (2018-2021). The expression levels of miR-663a, miR-663b, and miR-199a in the serum of 25 patients with metastatic breast cancer versus 15 healthy individuals were determined by the real-time polymerase chain reaction method. The response to treatment was followed up in a 24-month period. All patients were treated with second-line medications. Two or more combinations of these drugs were used: gemcitabine, Navelbine®, Diphereline®, Xeloda®, letrozole, Aromasin®, and Zolena®. Statistical analyses were performed in SPSS 21.0 and GraphPad Prism 6 software. The expression levels were presented as mean±SD and analyzed by Student's t test. Results: The results and clinicopathological features of patients were analyzed by t test. The statistical analysis showed that miR-663a expression was related to human epidermal growth factor receptor 2 (HER2) status and was significantly lower in the HER2+ than HER2- group (P=0.027). Moreover, the expression of miR-199a and miR-663b was significantly correlated with the response to treatment, in which the expression of miR-199a was higher in the poor-response group (P=0.049), while the higher expression of miR-663b was seen in the good-response group (P=0.009). Conclusion: These findings state that the high plasma level of miR-199a and the low plasma level of miR-663b may be related to chemoresistance in patients with metastatic breast cancer. [ABSTRACT FROM AUTHOR]

The emergence of resistance to antiretroviral drugs is the main problem in their long-term efficacy and by considering the wide use of protease inhibitors (PIs), monitoring drug resistance mutations is necessary. Therefore, this study aimed to investigate the PIs drug resistance mutations in Iranian patients as well as subtyping using bioinformatics analysis. Fifteen Iranian patients living with Human Immunodeficiency Virus (HIV) (PLWH) were examined. RNA was used to amplify and sequence the HIV protease gene; also, HIV viral load was determined for all samples. The sequencing results were analyzed by several strong bioinformatics tools to determine the drug-resistance mutations and HIV subtypes. Some polymorphisms in the protease gene were recognized; however, there was no significant rate of major or minor drug resistance mutations in our studied patients. Subtyping analysis revealed the new subtype (D) and the previously reported ones, A and CRF-AD 35, in patients. This study confirmed that the resistance mutations and genetic polymorphisms of the protease region are rare in Iranian-infected patients that can be concluded that prescribing protease inhibitor class in HIV-infected patients is promising in controlling HIV in Iran. In addition, conducting periodic studies to determine the new mutations and the rate of drug resistance to PIs in Iranian individuals highlights the importance of WHO guidelines that recommends monitoring of genotypic-resistance testing and investigation of mutations in HIV-related genes. [ABSTRACT FROM AUTHOR]

Background and objectives: Urinary tract infection (UTI) is one of the most common bacterial infections. Staphylococcus saprophyticus is a common Gram-positive bacterium that causes uncomplicated UTIs in women. The present study aimed to study the drug resistance pattern and phenotypic and genotypic variation of S. saprophyticus isolates from women with UTI in Gorgan, northern Iran. Methods: This study was performed from May 2018 to September 2020. During this time, 35 S. saprophyticus strains were isolated from patients with UTI. The antimicrobial patterns of the isolates were determined by a conventional method. Phenotypic criteria such as pigment production, mannitol fermentation, urease production, and 16SrRNA gene valuation were studied. Results: All isolates were sensitive to nitrofurantoin, gentamicin, and linezolid. S. saprophyticus isolates showed the highest level of resistance to penicillin (85.7%) and erythromycin (51.4%). A variation was detected among S. saprophyticus isolates in terms of pigment production i.e. about 51.4% showed yellow pigment in Muller Hinton agar, and 62.9% of the isolates were able to ferment mannitol sugar. Of 11 isolates that were sequenced for the 16SrRNA gene, only two isolates showed different patterns. Conclusion: Nitrofurantoin and trimethoprim-sulfamethoxazole are the antibiotics of choice for the treatment of UTI caused by S. saprophyticus in the study area. Due to the phenotypic and genotypic differences among S. saprophyticus isolates, typing of S. saprophyticus at the subspecies level is recommended. [ABSTRACT FROM AUTHOR]

Background and Aim: Since the incidence of various infections caused by Staphylococcus aureus increases, the use of effective antibiotics such as clindamycin has been growing to treat the systemic and local infections caused by such organisms. Antibiotic-resistant species are emerging and spreading in today's communities due to misuse of antibiotics and incomplete treatment, turning into a serious challenge for the health care system of countries, even in the advanced ones. Therefore, this study aims to investigate the prevalence of clindamycin-resistant S. aureus induced by macrolide resistance. Materials and Methods: In this cross-sectional descriptive study, 117 S. aureus isolates were collected from clinical samples of patients referred to Beâsat Hospital, Aja University of Medical Science, in Tehran, in Jan. 2019 to Jan. 2021, Tehran, Iran and were approved after diagnostic, microbiological, biochemical tests. Then, the data of antibiogram test were collected. Results & Conclusion: The results showed that 47% and 43% of the isolated samples were resistant to erythromycin and clindamycin, respectively. The prevalence of isolates with erythromycin resistance and induction resistance to clindamycin was approximately 38% and total induction resistance to clindamycin was 12%. The results indicate that antibiogram tests are required to identify induced resistance to clindamycin and to inform physicians about how to prescribe antibiotics in the treatment of infections caused by S. aureus. [ABSTRACT FROM AUTHOR]

The aims of the present study were to detect Escherichia coli in chicken distributed in Birjand, to investigate the prevalence of ESBL and AmpC beta-lactamases producers among them, and to identify their antibiotic resistance patterns. The study was conducted on 150 chicken samples, and the antimicrobial susceptibility patterns were determined by the Kirby–Bauer disk diffusion method. Phenotypic identification of ESBL and AmpC was performed by the combined disk test (CDT). The specific genes of ESBL and AmpC beta-lactamases were detected using two multiplex PCR (m-PCR) assays. According to our results, 116 out of 150 chicken samples were contaminated with E. coli. Moreover, the highest resistance of E. coli isolates was observed to trimethoprim/sulfamethoxazole (46%), ampicillin (40%), and amoxicillin (29.33%). In the molecular confirmation step, among 17 (11.33%) beta-lactamase producers, five samples contained the blaCTX-M14 gene (3.33%), two samples contained blaDHA (1.33%) and blaCTX-M3 gene (1.33%), and just one sample carried blaCMY-2 gene (0.66%). The blaSHV and blaTEM genes were not detected in any strains isolated from the chicken samples. This study showed the contamination of chicken with antibiotic-resistant E. coli. Therefore, it is recommended that veterinarians be more precautious in prescribing antibiotics. [ABSTRACT FROM AUTHOR]

The prevalence, antibiotic resistance, and virulence characteristics of Staphylococci from hospitals, livestock, municipals, and poultry wastewaters were investigated in Ardabil, Iran. From 155 staphylococcal isolates, 44.5% were coagulase-positive Staphylococcus (CoPS) and 55.5% were coagulase-negative Staphylococcus (CoNS) spp. Both CoPS and CoNS species were mainly found in hospital and poultry wastewater samples. The most prominent CoPS and CoNS species were Staphylococcus aureus at 80% and Staphylococcus xylosus at 37%. Methicillin resistance was found in 2% of S. aureus isolates. Overall, 49.2% of CoPS and 47.6% of CoNS isolates exhibited multidrug resistance phenotypes. CoPS isolates were the most resistant to penicillin (89%) and erythromycin (62%) and CoNS isolates exhibited the highest resistance to erythromycin (55%) and tetracycline (49%). Inducible clindamycin resistance was detected in 11% of S. aureus isolates. The ermC and aac genes were detected as the most common macrolide–lincosamide–streptogramin B and aminoglycoside-resistance encoding genes in 82.5 and 22.5% of S. aureus isolates, respectively. Most of the S. aureus isolates were positive for multiple virulence factors. The methicillin-resistant S. aureus isolates belonged to SCCmec type V. A new spa type t19215 was also identified. The occurrence of multidrug-resistant S. aureus with diverse genetic resistance and virulence background in wastewater is of great health concern. [ABSTRACT FROM AUTHOR]

There are limited studies on the antibiotic resistance patterns of slowly growing mycobacteria (SGM) species and their related gene mutations in Iran. This study aimed to elucidate the antibiotic susceptibility profiles and the mutations in some genes that are associated with the antibiotic resistance among SGM isolates from Iran. The SGM strains were isolated from sputum samples of suspected tuberculosis (TB) patients. SGM species were identified by standard phenotypic tests and were assigned to species level by amplification and sequencing of the dnaK gene. The minimum inhibitory concentration (MIC) of eight antibiotics was determined using broth microdilution method. The mutations in rrl, rpoB, gyrA, and gyrB genes were investigated in clarithromycin, rifampin, and moxifloxacin resistant isolates using sequencing method. A total of 77 SGM isolates including 46 (59.7%) Mycobacterium kansasii, 21 (27.3%) Mycbacterium simiae, and 10 (13%) Mycobacterium avium complex (MAC) were detected. The amikacin and linezolid with the susceptibility rates of 97.4% and 1.3% were the most and the least effective antibiotics, respectively. All MAC and M. simiae isolates, and 32 (69.6%) M. kansasii strains had multiple-drug resistance (MDR) profiles. The rrl, rpoB, gyrA, and gyrB genes showed various mutations in resistant isolates. Although the current study showed an association among resistance to the clarithromycin, rifampin, and moxifloxacin with mutations in the relevant genes, further research using the whole-genome sequencing is needed to provide a clearer insight into the molecular origins of drug resistance in SGM isolates. [ABSTRACT FROM AUTHOR]

Background: Microbial infections and the resistance to antibacterial drugs are on the rise, and scientists are in search of the safest and most effective approach to overcome them. Medicinal plants are potentially effective against many microorganisms. Therefore, this study was planned to examine the antibacterial properties and cytotoxicity of the extracts of Allium sativum and Myrtus communis against bacteria that cause nosocomial infections. Methods: A. sativum and M. communis were collected from the northern regions of Iran during the spring. After preparing the hydroalcoholic extracts of A. sativum and M. communis, the minimum inhibitory and bactericidal concentrations (MIC & MBC) were determined. The cytotoxicity of the extracts was asseyed in normal cells and Hu02 fibroblast cell line. Results: The MIC and MBC of A. sativum (62.5 mg/mL) against Salmonella enterica were similar. Also, the MIC of A. sativum and M. communis against Acinetobacter baumannii and Pseudomonas aeruginosa were similar (62.5 & 15.6 mg/mL), respectively. The viability percentage of skin fibroblasts after treatment for 48 hours with the extract of A. sativum was significantly higher than that of M. communis. Conclusion: Both extracts from A. sativum and M. communis demonstrated good antimicrobial properties. Based on the results, the safe antibacterial potential of the extracts may be used as alternative agents to fight against nosocomial bacterial infections. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most common and aggressive primary malignant brain tumor with poor prognosis and high potential of dispersion to other brain tissues in adult. Effective and modern choices of treatment including chemotherapy with alkylating agents marginally extend survival of GBM. However, alkylating agents can lead to highly harmful mismatch during DNA replication causing apoptosis and cell death. Accordingly, O6-Methylguanine-DNA methyltransferase (MGMT) removes alkyl adducts, thereby causing resistance to alkylating drugs. Single-Nucleotide Polymorphisms (SNPs) in MGMT promoter region may play a role in the regulation of MGMT expression and prediction of glioma development risk. In order to evaluate the clinical significance of rs1625649 SNP in the MGMT promoter region of glioblastoma, genomic DNA from a series of 54 patients with GBM and 50 healthy individuals in Iranian population were collected for tetra ARMS PCR amplification. None of the "A" or "C" alleles were associated with tumor occurrence, the "AA" genotype was more frequent in healthy subjects, and the "AC" genotype was 4.6 times more common in patients with GBM. The longest survival time was observed in the "CC" genotype; however, this difference was not statistically significant. On the other hand, homozygous rs1625649 (AA genotype) was significantly associated with a better survival than the cases with heterozygous rs1625649 (CA genotype) or wild type rs1625649 (CC genotype), predicting better response to temozolomide-based chemotherapy. [ABSTRACT FROM AUTHOR]

Background and Aim: Shigella is the causative agent of shigellosis in the world. Antibiotic treatment is important in this bacterium, but recently Shigella species containing the aph, aadE, aacA-aphD genes have shown resistance to aminoglycosides and have hampered the treatment process. Therefore, the aim of this study is a molecular investigation of Shigella dysenteriae aminoglycoside resistance genes isolated from children and its expression under the influence of curcumin nanoparticles. Materials and Methods: In this study, 60 diarrhea samples collected from Tehran hospitals in 2022 were used. Shigella dysenteriae isolates were identified by biochemical and microbial tests. The presence of aadE, aacA-aphD, and aph genes was confirmed by the Multiplex-PCR method. Then, real-time PCR was used to investigate the expression of aadE gene in the presence of curcumin nanoparticles. Results: From the 60 diarrhea samples examined, 12 strains (40%) of Shigella dysenteriae were identified by biochemical tests. Ten isolates (83.3%) carried the aadE gene, six isolates carried the aacA_aphD gene, and one isolate carried the aph gene. The Sub MIC value of curcumin nanoparticles on aadE gene expression is 128 µg/mL, and the Fold Change for this gene is -1.03. Conclusion: Considering the presence of aadE gene in 83.3% of S. dysenteriae isolates, it is important to investigate the presence of this gene in providing a suitable treatment model for patients infected with this bacterium, as well as the expression of aadE gene as the most common one. The expression of the aminoglycoside resistance gene was reduced to a relative amount in the presence of curcumin nanoparticles. Therefore, curcumin nanoparticles can be a suitable alternative for the treatment of strains carrying aminoglycoside resistance genes. [ABSTRACT FROM AUTHOR]

In World War I, sulfur mustard or mustard gas was used as a chemical weapon for the first time. Years later, during the imposed war (eight years of holy defense) against the Islamic Republic of Iran, Iraq used this poisonous gas against the soldiers and people of Iranian cities. Many years after the war, many chemical veterans still suffer from its effects. Mustard gas is a strong alkylating substance with cytotoxic and mutagenic properties, which causes blisters in mucous membranes and skin when it comes in contact with the skin. It is usually a colorless or amber-yellow oily liquid. In high concentrations, it has a disgusting smell similar to horseradish, onion, or garlic, which is mostly due to contamination with ethyl sulfide and other byproducts of its synthesis. Various studies have proven that long-term exposure to this toxic gas can lead to respiratory disorders and lung cancer. Considering the drug resistance and special conditions of chemical veterans with lung cancer, one of the new methods proposed for their treatment is the use of oncolytic viruses. The purpose of this study is to review the therapeutic potential of oncolytic viruses in the treatment of lung cancer caused by chemical warfare agents. [ABSTRACT FROM AUTHOR]

Background and Aim: Carbapenem-resistant Enterobacteriaceae (CRE) are rapidly growing, which makes it vital to detect antibacterial activity. However, the carbapenem family does not have an automated antimicrobial susceptibility testing card. So the aim of this study was to identify the prevalence of carbapenemase-producing strains of Gram-negative bacteria and determine their antibiotic susceptibility pattern in Tehran, Iran. Materials and Methods: In this cross-sectional study, between 2019 and 2020, 1600 samples were taken from the Masih Daneshvari hospital's laboratory in Iran. Utilizing standard biochemical methods, all isolated bacteria were identified. The common Kirby-Bauer Disc diffusion method was used for antimicrobial susceptibility testing. A real-time polymerase chain reaction was used to evaluate the molecular detection of genes producing carbapenemase. Results: Of 1502 (94.7) Gram-negative bacilli, 37.3% isolates were Pseudomonas aeruginosa, 30.6% Acinetobacter baumannii, 16.5% Klebsiella, 9.3% Escherichia coli, 0.6% Pseudomonas multophila, 0.4% Neisseria1105 (73.5%) isolates were carbapenem-sensitive, while the remaining 397 (26.5%) isolates were carbapenem-resistant. Molecular testing of this sample showed that 80% of tested isolates had resistance genes to at least one antibiotic resistance gene. The following carbapenemase genes were most frequently detected among resistant strains: blaimp (35%), blavim (20%), blakpc (15%), blaoxa -48 (10%), blandm (10%), and blages (10%). Conclusion: From this study authors can conclude that carbapenemase-producing Enterobacteriaceae is increasing in Iran and the use of phenotypic methods for detection of CPEs showed good sensitivity. Before prescribing antibiotics to patients, this test should be performed. [ABSTRACT FROM AUTHOR]

Background and Objectives: Vibrio fluvialis is a Gram-negative, bacillus-shaped, curved bacterium known as an emerging pathogen. There are reports of outbreaks caused by this bacterium worldwide. Iran, especially Qom province, is an endemic region for gastrointestinal diseases caused by Vibrio species. So, the aim was to isolate V. fluvialis from clinical and environmental samples. Materials and Methods: During six months, 363 clinical and surface water samples were evaluated. The samples were cultured on specific media, and all incubated for 24 hours at 37°C. Suspicious colonies were evaluated by Gram staining and biochemical tests. The BD Phoenix automated microbiology system was used for the final confirmation of the isolated bacteria. Evaluation of antibiotic resistance of isolated strains was also performed according to CLSI standard. Results: Eight cases (2.2%) of V. fluvialis, including seven from surface water samples (87.5%) and one from clinical samples (12.5%), were isolated. Based on antimicrobial susceptibility testing, all V. fluvialis isolates were susceptible to amikacin, gentamicin, trimethoprim/sulfamethoxazole, ciprofloxacin, tetracycline, ceftazidime, and chloramphenicol. High-level resistance to ampicillin and amoxicillin/clavulanate was also observed. V. fluvialis-infected patient had a mild fever, watery diarrhea, vomiting, nausea, and abdominal cramps that were manifested after drinking contaminated water or eating contaminated vegetables. The patient's symptoms recovered without antibiotic therapy after four days, resulting in self-limiting disease. Conclusion: The current study is the first human case of V. fluvialis infection isolated in Iran. Therefore, monitoring of water and food samples should be done routinely. [ABSTRACT FROM AUTHOR]

Introduction Pulmonary diseases are amongst the most common causes of premature death and distressing disorders worldwide. This study aimed to detect the fastidious and routine infectious agents, and their drug resistance patterns in bronchoalveolar lavage (BAL) samples. Methods A total of 44 BAL samples were collected by bronchoscopy from patients with respiratory disorders hospitalized at 2 teaching hospitals in Ilam, Iran. The samples were cultured on routine bacterial culture media to identify the bacterial agents and calculate the colony count. Antibiotic susceptibility was determined by disk diffusion method according to the CLSI protocol. PCR was used to detect the fastidious bacteria Mycoplasma pneumoniae and Chlamydia pneumoniae using the 16srRNA specific primers and Legionella pneumophila using the mip specific primers. Results Overall, 100 bacterial isolates were isolated by culture from the 44 BAL samples including: Staphylococcus aureus (24, 31.2%), Streptococcus pyogenes (18, 23.4%), Enterococcus spp. (11, 14.3%), Acinetobacter baumannii (11, 14.3%), Pseudomonas aeruginosa (11, 14.3%), Enterococcus spp. (10, 13%), Micrococcus spp. (5, 6.5%), Staphylococcus epidermidis (5, 6.5%) and Klebsiella pneumoniae (5, 6.5%). PCR detected 4 positive samples (9.1%) for Chlamydia pneumoniae but no positive cases for Mycoplasma pneumoniae and Legionella pneumophila. Acinetobacter baumannii showed the highest resistance rate (81.8%) to aztreonam and ceftazidime. Seventy-five percent of the Staphylococcus aureus isolates were resistant to cefoxitin (MRSA) and 83.3% had the mecA gene. Vancomycin resistance was observed in 27.3% of the Enterococcus species (VRE). Resistance to piperacillin, cefotaxime, ciprofloxacin and imipenem was observed in 54.5%, 45.5%, and 36.4% of the Pseudomonas aeruginosa isolates, respectively. The frequency of organisms isolated from the ICU was higher (46%) than from other wards. Conclusions The presence of MRSA, cephalosporins-resistant Enterobacteriaceae as well as Pseudomonas aeruginosa and Acinetobacter baumannii resistant against piperacillin, imipenem, cefotaxime, aztreonam and ciprofloxacin amongst different wards, especially the ICU ward of the surveyed hospitals, is a major healthcare concern and it is necessary to wisely scrutinize the preventive strategies for antibiotic resistant infections. [ABSTRACT FROM AUTHOR]

Background and Aim: Despite significant progress in Hepatitis B Virus (HBV) treatment, the emergence of drug resistance mutations is a main challenging health threat. The data is lacking regarding circulation mutant strains in northeastern Iran; therefore, the present study was conducted to investigate HBV reverse transcriptase (RT) inhibitors drug resistance mutations in a group of treatment naïve patients in Mashhad, Iran. Materials and Methods: In this study, 25 patients were included. The genomic DNA was extracted from serum samples, and the RT gene of HBV was amplified using specific primers. The PCR products were then subjected to gel electrophoresis and were next sent for sequencing. Finally, the sequences were analyzed using the HBVseq database, mutation list analysis software supported by Stanford University (https://hivdb.stanford.edu). Results: The mean age of the patients was 42.7±16.5. Among the patients, 56% were men. Among 23 cases (92%), no resistance mutation was observed, while 2 cases showed mutations outside the YMDD motif of viral reverse transcriptase causing Lamivudine or Entecavir resistance. The detected mutations included: rt T184A, S202I, S202H, V180I, I169L, and V173L. All sequenced samples were identified as genotype D. Conclusion: Lamivudine/Entecavir resistant variants are circulating in a minority of treatment naïve patients, which may indicate transmission of mutated stains to these patients or may be due to prolonged replication of the virus. This finding might be considered an alarm for increasing circulating mutant variants. [ABSTRACT FROM AUTHOR]

Background and Aim: Ornamental birds can serve as a reservoir for the virulent and antibiotic-resistant bacterium Escherichia coli. They can also play a role in transmitting these strains to humans. Therefore, obtaining information regarding drug resistance and virulence potential of the bacteria isolated from ornamental birds can contribute to disease treatment or prevention of pathogen transmission to humans. The present study was conducted to investigate the pattern of antibiotic resistance and virulence of Escherichia coli bacterium isolated from ornamental birds in Guilan province, Iran. Materials and Methods: Escherichia coli isolates were obtained from the feces of 80 apparently healthy ornamental birds in Rasht (Guilan, Iran) and were identified based on culture and biochemical tests. The antibiotic resistance pattern was determined using the disk diffusion method, and the frequency of virulence genes was investigated in test isolates using polymerase chain reaction. Results: Overall, 32 E. coli isolates were obtained from fresh feces of ornamental birds. In this study, 14 isolates (43.75%) had multiple drug resistance, and one extended-spectrum beta-lactamase-producing isolate was identified. Isolates were most sensitive to gentamicin (90%), and the highest resistance was associated with penicillin (90%). The frequency of iroN, ompT, hlyF, iss, and iutA genes in fecal isolates of ornamental birds was 28.12%, 34.37%, 40.62%, 30%, and 43.75%, respectively, and 25% of isolates were identified as avian pathogenic E. coli. Conclusion: The results of this study indicate the virulence potential and drug resistance in fecal E. coli isolates in ornamental birds in Rasht. The spread of these strains in the environment can endanger the health of owners and the whole society. [ABSTRACT FROM AUTHOR]

Background: Disinfection has a fundamental role in the control of pathogens in the hospital environment. This study was designed to assess the efficacy and functional impact of disinfectants in reducing pathogens related to healthcare associated infections (HAIs) in hospitals., Methods: This observation study was conducted at three university hospitals in Gorgan, Iran, from May to Oct 2023. The data including used disinfectants and microbiological examination were obtained from the infection control unit of each hospital., Results: The results showed that a variety of disinfectants from intermediate to high levels were employed in accordance with the World Health Organization (WHO) protocols. The microbial result revealed that 31.6% (286 out of 906) of the sample had at least one microorganism. Among identified organisms, Bacillus spp. were the predominant species followed by Staphylococcus epidermis, fungus genera, Enterobacter spp., Enterococcus spp., Pseudomonas spp., Escherichia coli, Alcaligenes spp., Staphylococcus aureus, Citrobacter spp., Corynebacterium spp., Klebsiella spp., Acinetobacter spp., Micrococcus spp., Staphylococcus saprophyticus, and Serratias spp. The highest prevalence rates of microorganisms were observed in the wards of ICU, emergency, internal medicine, and women's ward. The chi-square test revealed a significant relationship between the presence of organisms and hospital wards (P < 0.05)., Conclusion: The presence of pathogens indicates a defect in the disinfection process, probably due to both little attention to disinfection protocols and multidrug resistance. It is not yet possible to eliminate pathogens from the hospital environment, but it can be minimized by education intervention, standardizing disinfecting processes, and monitoring by the infection control committee., (© 2024. The Author(s).)

Background: The emergence of Streptococcus agalactiae infections in patients with bacteremia is increasing. It is crucial to investigate the epidemiology, molecular characteristics, biofilm status, and virulence analysis of Streptococcus agalactiae in these patients., Methods: In this cross-sectional study, 61 S. agalactiae isolated from blood infection were subjected to characterization through antimicrobial susceptibility tests, biofilm formation, multilocus sequence typing (MLST), and PCR analysis for detecting resistance (tet and erm family) and virulence genes (alp2/3, alp4, bca, bac, eps, rib, lmb, cylE, and pilus island genes)., Results: Overall, 32.7% of the isolates demonstrated an inducible clindamycin resistance phenotype. The results showed that 49.2, 24.6, and 8.2% of confirmed Streptococcus agalactiae strains were classified as strong, intermediate, and weak biofilm-forming strains, respectively. tet(M) (57.1%) was recovered most, followed by tet(M) + tet(L) (14.3%), tet(S) + tet(K) (10.7%), tet(M) + tet(K) (8.9%), tet(M) + tet(K) + tet(O) (5.4%), and tet(S) + tet(L) + tet(O) (3.6%). Three virulence gene profiles of cylE, lmb, bca, rib (24.6%; 15/61), cylE, lmb, rib, alp3 (19.7%; 12/61), and cylE, lmb, bac, rib (16.4%; 10/61) were detected in approximately two-thirds of the isolates. MLST revealed that the 61 isolates belonged to six clonal complexes, including CC1 (49.2%), followed by CC12 (18%), CC19 (13.1%), CC22 (9.8%), CC17 (6.6%), and CC283 (3.3%), and 11 different sequence types (STs), including ST1 (24.6%), ST7 (14.8%), ST918 (13.1%), ST2118 (9.8%), ST19 (9.8%), ST48 (6.6%), ST1372 (4.9%), ST22 (4.9%), ST40 (4.9%), ST734 (3.3%), and ST283 (3.3%). Remarkably, all CC1 and CC12 isolates, three-fourths of CC19, and half of CC22 were confirmed as biofilm producers. Conversely, CC17 and CC28 isolates were found to be nonproducers. The occurrence of strong biofilm formation was limited to specific CCs, namely CC1 (34.4%), CC12 (8.2%), CC19 (3.3%), and CC22 (3.3%)., Conclusion: The high prevalence of CC1 and CC12 clones among S. agalactiae strains reflects the emergence of these lineages as successful clones in Iran, which is a serious concern and poses a potential threat to patients., (© 2024. The Author(s).)