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Highlights: (1) Blood culture is the gold standard for the diagnosis of bacterial infections. (2) Bone marrow culture is more sensitive than blood culture even in patients with enteric fever receiving antibiotics. (3) Microscopic agglutination test is considered the gold standard for diagnosing leptospirosis; however, now IgM ELISA and polymerase chain reaction (PCR) are more frequently used for diagnosis. (4) Tuberculosis is diagnosed with the help of nucleic acid amplification tests like Xpert MTB/RIF Ultra which also detects rifampicin resistance. Other tests include microscopy, Lowenstein-Jensen and mycobacteria growth indicator tube culture, line probe assay. (5) Tropical rickettsial infections are diagnosed by serological reactions (Weil-Felix, ELISA for antibodies) and PCR. (6) For Brucellosis culture from blood, bone marrow or tissue specimens remain the mainstay in diagnosis. (7) Dengue, Zika, Crimean-Congo hemorrhagic fever, Ebola, hantavirus, rabies are diagnosed with reverse transcriptase-polymerase chain reaction. Serological tests like IgM ELISA or paired sera samples for IgG are also used for diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: In this study, daptomycin minimum inhibitory concentrations (MICs) for Staphylococcus aureus isolates were determined using Etest strips and were correlated with staphylococcal cassette chromosome mec (SCCmec) types and Panton–Valentine leukocidin (PVL) gene positivity. In total, 60 meticillin-resistant S. aureus (MRSA) and 60 meticillin-susceptible S. aureus (MSSA) isolates from clinical samples were subjected to antimicrobial susceptibility testing by disk diffusion according to Clinical and Laboratory Standards Institute guidelines, polymerase chain reaction (PCR) detection of PVL and mecA genes, and SCCmec typing. Daptomycin MICs were determined using Etest strips. The mecA gene was present in all MRSA isolates and was absent in 59 MSSA isolates. The PVL gene was present in 41 MRSA isolates and 25 MSSA isolates. Amongst the MRSA isolates, 10 were SCCmec type III, 27 were SCCmec IV and 23 were SCCmec V. Moreover, 26 SCCmec IV and 15 SCCmec V isolates were PVL-positive. All SCCmec III isolates were multidrug-resistant and PVL-negative. Daptomycin MICs ranged from 0.047μg/mL to 1μg/mL for MRSA and from 0.19μg/mL to 1μg/mL for MSSA. All MRSA and MSSA isolates were susceptible to daptomycin. Although SCCmec III MRSA and PVL-positive MSSA were resistant to more antimicrobial classes than SCCmec IV and V MRSA and PVL-negative MSSA, there does not appear to be a significant correlation between SCCmec types, PVL positivity and daptomycin MICs. MICs were not as low as expected for a newly introduced drug. [Copyright &y& Elsevier]

India has a high number of drug-resistant tuberculosis cases. Patient records were screened to determine risk factors possibly associated with monoresistance and multidrug-resistant tuberculosis (MDR-TB) in comparison with patients with susceptible TB. We retrospectively screened and selected 250 patient records from a tertiary care centre, in which detailed clinical histories were provided. Of the 250 patients, 10 had isoniazid monoresistant TB, 184 patients had MDR-TB, and 56 patients had TB susceptible to first-line drugs. Binary regression analysis revealed that previous treatment with a fluoroquinolone and an injectable other than streptomycin (odds ratio (OR) 3.889, 95% confidence interval (CI) 1.828-8.272) was associated with MDR-TB. Previous history of TB (OR 0.697, 95% CI 0.363-1.338) and the presence of cavities on radiographs (OR 0.371, 95% CI 0.160-0.862) did not show any association. None of these reported risk factors were associated with isoniazid monoresistance. In conclusion, a history of previous treatment with a fluoroquinolone and an injectable other than streptomycin was found to be a risk factor for MDR-TB. [ABSTRACT FROM AUTHOR]

A well-structured digital database is essential for any national priority project as it can provide real-time data analysis and facilitate quick decision making. In recent times, particularly after the COVID-19 pandemic, invasive fungal infections (IFIs) have emerged as a significant public health challenge in India, affecting vulnerable population, including immunocompromised individuals. The lack of comprehensive and well-structured data on IFIs has hindered efforts to understand their true burden and optimize patient care. To address this critical knowledge gap, the ICMR has undertaken a Pan-India pioneer initiative to develop a network of Advanced Mycology Diagnostic research centres in different geographical zones of the country (ICMR-MycoNet). Under the aegis of this project, a clinical registry on IFIs in the ICUs is initiated. This process paper presents a detailed account of the steps involved in the establishment of a web-based data entering and monitoring platform to capture data electronically, ensuring robust and secure data collection and management. This system not only allows participating ICMR-MycoNet centres to enter patient information directly into the database using standardized Case Report Form (CRF) but also includes data validation checks to ensure the accuracy and completeness of entered data. It is complemented by a real-time, web-based, and adaptable data visualization platform. This registry aims to provide crucial epidemiological insights, promote evidence-based hospital infection control programs, and ultimately improve patient outcomes in the face of this formidable healthcare challenge. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Extensive drug resistance acquired during treatment of multidrug-resistant tuberculosis" by J.P. Cegielski and colleagues, that was published in October 15, 2014 issue.

The article presents a study which reveals Carbapenem-resistant gram-negative bacilli and the emergence of New Delhi metallo 1 (NDM1) enzyme. The study isolated 310 carbapenem-resistant gram-negative bacilli consists of enterobacteriaceae, pseudomonas species, and acinetobacter species and molecularly identified NDM1. Results from the stool samples of patients treated with carbapenem reveal that none of the enterobacteriaceae isolates were carbapenem resistant.

Fibrous dysplasia is also called fibrocystic disease, osteitis fibrosa localisata, focal osteitis fibrosa, fibro osteodystrophy, and Jaffe-Lichtenstein. It is an asymptomatic regional alteration of bone in which the normal architecture of bone is replaced by fibrous tissue and nonfunctional trabeculae-like osseous structures. Fibrous dysplasia may be monostotic or polyostotic, with or without associated endocrine disturbances. Here, we are discussing two cases with monostotic fibrous dysplasia of maxilla with emphasis on various radiographic features that the lesion shows during its different stages. [ABSTRACT FROM AUTHOR]

Purpose: Incidence of carbapenem-resistant Gram-negative infections has risen alarmingly all across the globe, both in developed and developing countries alike. The purpose of this study was to assess whether challenges of life-threatening infections with very high resistance pattern can be successfully addressed by a modified approach.Methods: This is a retrospective study of 26 patients with osteoarticular and soft tissue infections with carbapenem-resistant Gram-negative bacilli treated between 2001 and 2017 with at least two year follow-up after stopping antibiotics. All were treated by a multispecialty team approach with primary aim of "source control at the earliest and avoiding recurrence at all cost". The protocol involved opting for early compromises especially in at "risk individuals", such as resorting to early amputations, especially if salvage meant multiple bony and soft tissue reconstructive procedures, explanation of prosthesis than staged revision, avoiding internal fixations, opting for shortest possible time in external fixators with reshaping and telescoping bone ends to get bony stability and increase surface area even if it meant compromising length.Results: There were five amputations, two excision arthroplasty of hip, many minor but acceptable malunions and shortening. However, lives of 24/26 patients could be salvaged, much better than most of the published data. The two patients who died had peri-prosthetic joint infection after total hip arthroplasty and presented very late in sepsis and died within days of explantation. Infection remission could be achieved in remaining patients.Conclusion: These "risk to life" cases can be successfully treated by lowering the aims and expectations from "excellent function to salvage of life and infection remission". Therein lies the "success" in these complex high-risk cases. [ABSTRACT FROM AUTHOR]

Introduction: Sepsis is a life-threatening condition caused due to dysregulated immune response to an infection and progressive immunosuppression. Reactivation of cytomegalovirus (CMV) occurs frequently in sepsis and is found associated with adverse outcomes. The study objective was to evaluate the association between incidence of CMV reactivation and immune alteration in sepsis-induced immunosuppression in patients with prolonged sepsis. Patients and methods: Patients admitted to intensive care unit (ICU), with severe sepsis and CMV immunoglobulin G (IgG) seropositivity, were prospectively enrolled. Other manifest immune suppression causes were excluded. Samples were collected on enrolment and further once a week until day 21 or death/discharge. CMV viral load was quantified using qPCR. Lymphocyte subset analysis (CD3+, CD4+, CD8+, CD19+, CD16+/CD56+, and CD25+CD127- regulatory T cells), human leukocyte antigen-DR isotype (HLA-DR) expression on monocytes, programmed death-1 (PD-1) expression on T lymphocytes, and proinflammatory (interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ)), anti-inflammatory cytokines levels (IL-2, IL-4, and IL-10) were analyzed by flow cytometry as markers for immunosuppression. Results: A total of 25 CMV IgG-positive patients and 11 healthy controls were included. CMV reactivation occurred in 20 patients. Patients with CMV reactivation had T-cell lymphopenia. PD-1 expression on CD4+ and CD8+ T cells was markedly elevated (p <0.02) in CMV-reactivated patients compared to nonreactivated patients. HLA-DR expression was significantly low on monocytes in all septic patients (p <0.01) compared to healthy controls. IL-6 levels showed elevation at day 7, whereas IL-10 was found to be significantly higher from day 0 in CMV-reactivated group. Conclusion: Our study concluded that immune suppression markers and cytokine levels in patients with severe sepsis were found to be significantly associated with the incidence of CMV reactivation. [ABSTRACT FROM AUTHOR]

Background & objectives: Linezolid (LZD) is increasingly being used in tuberculosis (TB) treatment. However, LZD resistance has already been reported, which is highly alarming, given its critical therapeutic role. This study was aimed to phenotypically and genotypically assess LZD resistance in Mycobacterium tuberculosis (MTB) isolates at a laboratory in a tertiary care centre in Mumbai, India. Methods: A sample of 32 consecutive LZD-resistant MTB isolates identified by liquid culture susceptibility testing was subjected to whole-genome sequencing (WGS) on the Illumina NextSeq platform. Sequences were analyzed using BioNumerics software to predict resistance for 12 antibiotics within 15 min. Results: Sixty eight of the 2179 isolates tested for LZD resistance by MGIT-based susceptibility testing (June 2015 to June 2016) were LZD-resistant. Thirty two consecutive LZD-resistant isolates were analyzed by WGS to screen for known mutations conferring LZD resistance. WGS of 32 phenotypically LZD-resistant isolates showed that C154R in the rplC gene and G2814T in the rrl gene were the major resistance determinants. Interpretation & conclusions: LZD resistance poses an important risk to the success of treatment regimens, especially those designed for resistant isolates; such regimens are extensively used in India. As LZDcontaining regimens increase in prominence, it is important to support clinical decision-making with an improved understanding of the common mutations conferring LZD resistance and their frequency in different settings. [ABSTRACT FROM AUTHOR]

Background: In the era of increasing drug resistance in pulmonary tuberculosis (TB), it is prudent to assess causes of poor response to anti tubercular therapy (ATT) and drug sensitivity pattern (DSP) in osteoarticular TB. Materials and Methods: As a part of Bombay Orthopaedic society's research project, members were asked to refer non responders to ATT to our institute. Cases were enrolled from October 2010 to March 2014. Deep tissue samples were obtained in all but five cases and subjected to a battery of tests including histopathology (HPE) and TB culture and sensitivity. The DSP was compared with the study performed by the principle author from 2004 to 2007 and published in 2009. Results: 39 male and 50 female patients with a mean age of 24.85 years (2–66) were included and classified in four groups after results. (1) Culture and HPE positive-36. 24 had MDR and three XDR TB. Primary resistance to even second line drugs and deterioration of DSP since last study was noted, (2) culture negative and HPE positive-21. The cause of poor response was surgical in more than half cases, (3) non representative samples or lost to follow-up-15, (4) TB mimics-16. Conclusion: There is increasing incidence of primary resistance to second line drugs, primary resistance in children and worsening of resistance patterns as compared to older studies. ATT initiation is a fateful decision and every attempt should be made to rule out TB mimics and establish DSP before initiation. [ABSTRACT FROM AUTHOR]

Introduction: Fungal osteoarticular/soft tissue infections (FOaSI) are an uncommon entity with protracted course due to variability in clinical picture, slow progression; resulting in misdiagnosis with empirical therapy. Recent studies have shown an alarming emergence of FOaSI in immunocompetent individuals with high mortality rates. This study recommends a protocol for managing these complex and confusing scenarios. Methodology: We have retrospectively analysed patients with FOaSI between January 2014 and December 2016, with a minimum 12 months follow up. Results: 8 cases (6 male, 2 female) with a mean age of 42.88 years (26-53) presented to us 45 days (3-365) after initial symptoms. They underwent mean 3 procedures before being diagnosed with a fungal infection. Deep tissue cultures grew 9 fungi and 6 bacteria, commonest fungus being Candida sp (n = 4), treated with appropriate antifungals and antibiotics. Infection remission was achieved in 7/8 (87.5%) cases at 27.1 months (19-45) follow-up with 1 mortality. Excellent functional results as per our criteria were seen in 5 cases (62.5%) with 1 talus excision, 1 ray amputation and 1 mortality. Conclusions: This study highlights the significance of implementing a simple rule such as obtaining fungal cultures in every case of bone and soft tissue infections. Standardisation of treatment may not be the ideal solution, since different fungi have different growth patterns and invasiveness. A simple protocol of customising the medico- surgical treatment with an open ended discussion between the surgeons, microbiologists, pathologists and infectious disease specialists forms the cornerstone to success. [ABSTRACT FROM AUTHOR]

The development and rollout of the Xpert® Mycobacterium tuberculosis/rifampicin assay for the GeneXpert platform is considered an important breakthrough in the fight against tuberculosis. Xpert though robust is known to have issues that occur with very low load of tuberculosis detection, wherein it is recommended to confirm resistance if resistance is not suspected using another genotypic test. [ABSTRACT FROM AUTHOR]

Background: The gastric microbiota has recently been implicated in the causation of organic/structural gastroduodenal diseases (gastric and duodenal ulcers, gastric cancer) in patients with Helicobacter pylori (H. pylori) infection. We aimed to ascertain, in patients harbouring H. pylori, the role of the gastric microbiota in the causation of symptoms (chronic dyspepsia) in the absence of organic disease.Methods: Seventy-four gastric biopsy samples obtained at endoscopy from patients with (n = 21) or without (n = 53) chronic dyspepsia, and that tested positive by the bedside rapid urease test for H. pylori infection, were cultured for detection of H. pylori and non-H. pylori organisms. The cultured organisms were identified by matrix-assisted laser desorption ionization time-of-flight mass spectroscopy (MALDI-TOF MS).Results: A total of 106 non-H. pylori isolates were obtained from 74 patients' samples. This included 33 isolates (median 2, range 1-2 per patient) from dyspeptic and 73 (median 2, range 1-2 per patient) from non-dyspeptic patients. These were identified from the Bruker Biotyper 2 database as Staphylococcus spp., Streptococcus spp., Lactobacillus spp., Micrococcus spp., Enterococcus spp., Pseudomonas spp., Escherichia spp., Klebsiella spp. and Bacillus spp., Staphylococcus and Lactobacillus were identified significantly more commonly in dyspeptics and Streptococcus, Pseudomonas, Escherichia coli and Klebsiella pneumoniae in non-dyspeptics. All identified organisms belonged to the phyla Firmicutes and Proteobacteria.Conclusions: There is a qualitative difference in the gastric microbial spectrum between patients harbouring H. pylori with and without chronic dyspepsia. Whether these organisms have an independent role in the development or prevention of dyspepsia or act in concurrence with H. pylori needs study. [ABSTRACT FROM AUTHOR]

The article reports the study on the challenges faced in the control and management of the disease due to the emergence of drug-resistant tuberculosis (DR). Topics discussed include lack of quality evidence in clinical and operational management of DR tuberculosis, individualized drug susceptibility testing (DST) for successful management of DR tuberculosis and importance of fluoroquinolone susceptibility in the management of multidrug-resistant (MDR) tuberculosis patients.

The article focuses on a study which examined the presence of carbapenem resistance in faecal samples from healthy individuals over a six month period. A Mueller-Hinton agar was used to test for the presence of extended-spectrum &Beta-lactamases (ESBL) in enterobacteriaceae. Results of the study showed that 23.9% of the samples were ESBL producers. It also identified Escherichia coli and Klebsiella species in five percent of the samples. The study did not found any carbapenem resistance.

The article presents a response by the authors on the results of a study on the Deferasirox-AmBisome Therapy (DEFEAT) for Mucormycosis which was published in the 2012 issue of this journal. The authors note that there is still a role for adjuvant deferasirox in patients who are subjected to a randomized controlled trial. A chart on the clinical characteristics and outcomes of patients treated with deferasirox is included.

Delayed diagnosis of drug resistance has been a major obstacle to proper management and control of drug-resistant tuberculosis (TB). Expanded access to rapid molecular diagnostics such as Xpert MTB/RIF has been helpful, but has generated confusion about how to interpret genotype-phenotype discordance. Optimal management is not clearly defined for patients with rifampin resistance by Xpert MTB/RIF but rifampin susceptibility by phenotypic testing. To resolve this discrepancy, we performed pyrosequencing of discordant isolates identified at a reference laboratory over a 6-month period. We present here strategies to address genotype-phenotype discordance using sequencing. [ABSTRACT FROM AUTHOR]

This study correlates MICs of rifampicin (RIF) and isoniazid (INH) with GenoType MTBDR plus assay results for drug-resistant Mycobacterium tuberculosis ( MTB ) clinical isolates. MICs of RIF and INH were established for 84 and 90 isolates, respectively, testing 7 concentrations of each drug. Genotypic resistance to each drug was determined by GenoType MTBDR plus assay with 50 representative mutations confirmed by pyrosequencing, with mutations in the rpoB gene associated with RIF resistance and mutations in the katG and/or inhA genes associated with INH resistance. Based upon the correlation of MICs with specific genetic profiles, relative resistance levels were established for each isolate. Results indicate that MTB phenotypic resistance, currently based upon the testing of isolate susceptibility to a single drug concentration, may be more accurately profiled via quantitative MICs, and therefore, the correlation of molecular diagnostic results with specific MICs may allow for more optimal treatment of infections. [ABSTRACT FROM AUTHOR]

Rhabdomyosarcoma (RMS) is a fast growing, highly aggressive malignant tumor, consisting of cells derived from the progenitor cells of myoblasts called satellite cells that exhibit a profound tendency for myogenesis. Accounts for about 5-6% of childhood cancers, occurring in the first 10 years of life. Annual incidence of RMS ranges from 5 to 8/million in Asian and Caucasian children. About 35% of RMS arises in the head and neck region, and are classified as parameningeal (PM), orbital, nonorbital and non-PM forms. PM tumors carry the worst prognosis, and are associated with a high rate of recurrence, and generalized metastases through the hematogenic and/or lymphatic routes. We present a case of 20-year-old male with an exuberant, rapidly increasing swelling of the floor of the mouth. Computed tomography scan, blood investigation, histopathological examination and desmin immuno histo chemistry staining marker, were aids that led to a definitive diagnosis. [ABSTRACT FROM AUTHOR]

Background: Drug-resistant tuberculosis (DR-TB) is a looming threat to tuberculosis control in India. However, no countrywide prevalence data are available. The burden of DR-TB in HIV-co-infected patients is likewise unknown. Undiagnosed and untreated DR-TB among HIV-infected patients is a major cause of mortality and morbidity. We aimed to assess the prevalence of DR-TB (defined as resistance to any anti-TB drug) in patients attending public antiretroviral treatment (ART) centers in greater metropolitan Mumbai, India. Methods: A cross-sectional survey was conducted among adults and children ART-center attendees. Smear microscopy, culture and drug-susceptibility-testing (DST) against all first and second-line TB-drugs using phenotypic liquid culture (MGIT) were conducted on all presumptive tuberculosis patients. Analyses were performed to determine DR-TB prevalence and resistance patterns separately for new and previously treated, culture-positive TB-cases. Results: Between March 2013 and January 2014, ART-center attendees were screened during 14135 visits, of whom 1724 had presumptive TB. Of 1724 attendees, 72 (4%) were smear-positive and 202 (12%) had a positive culture for Mycobacterium tuberculosis. Overall DR-TB was diagnosed in 68 (34%, 95% CI: 27%–40%) TB-patients. The proportions of DR-TB were 25% (29/114) and 44% (39/88) among new and previously treated cases respectively. The patterns of DR-TB were: 21% mono-resistant, 12% poly-resistant, 38% multidrug-resistant (MDR-TB), 21% pre-extensively-drug-resistant (MDR-TB plus resistance to either a fluoroquinolone or second-line injectable), 6% extensively drug-resistant (XDR-TB) and 2% extremely drug-resistant TB (XDR-TB plus resistance to any group-IV/V drug). Only previous history of TB was significantly associated with the diagnosis of DR-TB in multivariate models. Conclusion: The burden of DR-TB among HIV-infected patients attending public ART-centers in Mumbai was alarmingly high, likely representing ongoing transmission in the community and health facilities. These data highlight the need to promptly diagnose drug-resistance among all HIV-infected patients by systematically offering access to first and second-line DST to all patients with ‘presumptive TB’ rather than ‘presumptive DR-TB’ and tailor the treatment regimen based on the resistance patterns. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Continuous Infusion of beta-Lactam Antibiotics in Severe Sepsis: A Multicenter Double-Blind, Randomized Controlled Trial" by J M Dulhunty and coworkers and "Clinical Outcomes with Extended or Continuous Versus Short-Term Intravenous Infusion of Carbapenems and Piperacillin/ Tazobactam: A Systemic Review and Meta-Analysis" by M E Falagas and coworkers in the 2013 issue.

Background: Control of the global Tuberculosis (TB) burden is hindered by the lack of a simple and effective diagnostic test that can be utilized in resource-limited settings. TM Methods: We evaluated the performance of Truenat MTB™, a chip-based nucleic acid amplification test in the detection of Mycobacterium tuberculosis (MTB) in clinical sputum specimens from 226 patients with suspected pulmonary tuberculosis TM (TB). The test involved sputum processing using Trueprep-MAG™ (nanoparticle-based protocol run on a battery-operated device) and real-time PCR performed on the Truelab Uno™ analyzer (handheld, battery-operated thermal cycler). Specimens were also examined for presence of MTB using smear microscopy, liquid culture and an in-house nested PCR protocol. Results were assessed in comparison to a composite reference standard (CRS) consisting of smear and culture results, clinical treatment and follow-up, and radiology findings. Results: Based on the CRS, 191 patients had "Clinical-TB" (Definite and Probable-TB). Of which 154 patients are already on treatment, and 37 were treatment naïve cases. Remaining 35 were confirmed "Non-TB" cases which are treatment naïve cases. The Truenat MTB test was found to have sensitivity and specificity of 91.1% (CI: 86.1-94.7) and 100% (CI: 90.0-100) respectively, in comparison to 90.58% (CI: 85.5-94.3) and 91.43% (CI: 76.9-98.2) respectively for the in-house nested PCR protocol. Conclusion: This preliminary study shows that the Truenat MTB test allows detection of TB in approximately one hour and can be utilized in near-care settings to provide quick and accurate diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we aimed to correlate the analytical performance of SD BIOLINE TB Ag MPT64 Rapid Test kit (MPT64 assay) with the mycobacterial growth unit (GU) reported by the BACTEC MGIT 960 (MGIT 960) instrument. A total of 394 culture isolates reported positive by MGIT 960 were processed daily (until ‘day 4’) with the MPT64 assay until a positive MPT64 result was obtained and their GU values were noted daily before MPT64 testing. Based on this correlation of MPT64 positivity and corresponding GU values, a GU cut-off was determined. In the validation phase, with the experimentally determined GU cut-off value, 99.1% (576/581) of culture isolates were correctly identified as MTB within 2 days from instrument positivity. All results were available using a single-MPT64 assay strip, making the assay cost-effective. Thus, systematic implementation of the MPT64 assay proved to be cost-effective in a high-throughput laboratory without any delay in patient reporting. [Copyright &y& Elsevier]

Background: The emergence of resistant tuberculosis (TB) is a major setback to the global control of the disease as the treatment of such resistance is complex and expensive. Use of direct detection of mutations by molecular methods could facilitate rapid diagnosis of resistance to offset diagnostic delays. We evaluated the performance of the Genotype MTBDRsl (Hain Life Sciences) for the detection of second line resistant TB directly from stored smear positive sputum sediments. Methodology/Principal Findings: The assay showed a diverse range of sensitivity and specificity, 91.26% [95% CI, 84-96] and 95.5% [95% CI, 87-99] for FQ (PPV ~ 97% & NPV ~ 87.67%), 56.19% [95%CI, 46-66] and 81% [95%CI, 66-91] for EMB (PPV ~ 88.06% & NPV ~ 43.21%) and 100% for SLD. Diagnostic accuracy for FQ, SLD and EMB was 94%, 100% and 63.51%, respectively. 1.17% (2/170) were heteroresistance strains, where the heteroresistance was linked to rrs gene. A varying rate of validity was observed 100% (170/170) for FQ, 94.11% (160/170) for EMB, 88.23% (150/170) for SLD. Conclusions/Significance: Genotype MTBDRsl is simple, rapid, economical assay that can be used to detect commonly known resistance associated with Fluoroquinolone, second line injectable drugs and ethambutol. The assay detects the targeted resistance in less time as compared to phenotypic DST. But due to low NPV to FQ (88%) and EMB (43.21%), the assay results must be interpreted in coordination with the phenotypic DST. [ABSTRACT FROM AUTHOR]

Background: Unsuccessful treatment outcomes among patients with multi-/extensively- drug resistant tuberculosis (TB) have hampered efforts involved in eradicating this disease. In order to better understand the etiology of this disease, we aimed to determine whether single or multiple strains of Mycobacterium tuberculosis (MTB) are localized within lung cavities of patients suffering from chronic progressive TB. Methodology/Findings: Multiple cavity isolates from lung of 5 patients who had undergone pulmonary resection surgery were analyzed on the basis of their drug susceptibility profile, and genotyped by spoligotyping and 24-loci MIRU-VNTR. The patients past history including treatment was studied. Three of the 5 patients had extensive drug resistant TB. Heteroresistance was also reported within different cavity isolates of the lung. Both genotyping methods reported the presence of clonal population of MTB strain within different cavities of the each patient, even those reporting heteroresistance. Four of the 5 patients were infected with a population of the Beijing genotype. Post-surgery they were prescribed a drug regimen consisting of cycloserine, a fluoroquinolone and an injectable drug. A 6 month post-surgery follow-up reported only 2 patients with positive clinical outcome, showing sputum conversion. Conclusion: Identical spoligotype patterns and MIRU-VNTR profiles between multiple cavities of each patient, characterize the presence of clonal population of MTB strains (and absence of multiple MTB infection). [ABSTRACT FROM AUTHOR]

A letter to the editor about the prevalence of carbapenem resistance in clinical isolates of Enterobacteriaceae because of the production of metallo-β-carbapenemases (MBL) is presented.

A letter which discusses the use of the Gene Xpert Mycobacterium tuberculosis (MTB)/rifampin (RIF) semi-automated assay for screening MTB infection and RIF resistance is presented. The authors acknowledge the simplicity of the assay in addition to its high level of sensitivity. The endorsement given by the World Health Organization (WHO) to the assay is mentioned. Results of assessments made to evaluate performance of this assay are also reported.