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The rate of pandrug-resistant Acinetobacter baumannii strains is on the rise in all continents. This bacterium can acquire resistance to all antibiotics, even to colistin. Alterations in the lipid A or/and the two-component pmrAB were earlier detected in colistin resistance. We investigated and analyzed two strains of A. baumannii (ABRC1 and ABRC2) isolated from two patients admitted to intensive care unit with a septic shock. Both strains were resistant to all tested antibiotics including colistin with a MIC >256 mg L−1. Colistin resistance genes (pmrA , pmrB, lpxA, lpxC, lpxD, and lpsB) of two strains (ABRC1 and ABRC2) were investigated by PCR and sequencing. Obtained nucleic acid sequences were aligned with reference sequences of ATCC 19606 and 17987. In this study two amino acid mutations, N287D in the lpxC gene and E117K in the lpxD gene, were detected in both ABRC1 and ABRC2 strains. ABRC1 had an additional H200L mutation in the pmrA gene. Both colistin resistant strains harbored the same A138T mutation in the pmrB gene. The ABRC2 strain also had an alteration in the kinase domain, specifically an R263S substitution of the histidine kinase domain. Three identical mutations were found in the lpsB gene of both A. baumannii strains: Q216K + H218G + S219E. As a result, a newly deduced protein sequence in both ABRC1 and ABRC2 strains differed from those described in ATCC 17978 and 19606 strains was determined. Colistin resistance is multifactorial in A. baumannii. In our study we detected novel mutations in colistin resistant A. baumannii clinical isolates. [ABSTRACT FROM AUTHOR]

Hypervirulent Klebsiella pneumoniae is an emerging pathogen that has gained attention due to its increased ability to cause infections even in healthy individuals. The aim of this study is to investigate virulence factors in K. pneumoniae strains isolated from clinical specimens and their association with carbapenem resistance. The study was conducted on 260 isolates identified between 2018 and 2023 at the Mohammed V Military Teaching Hospital in Rabat, Morocco. The isolates were categorized based on their susceptibility to antibiotics. The hypermucoviscosity was determined by a string test, while the presence of capsular serotypes and virulence genes were identified by PCR. Among our strains, 6.2% (n = 16) exhibited hypervirulent characteristics, 56% were resistant to carbapenem. Notably, 5.7% (n = 6) of carbapenem-resistant isolates expressed the hypermucoviscous phenotype, while 1.5% (n = 2) of carbapenem-susceptible K. pneumoniae isolates exhibited the same trait. In our study, we found that a total of 10 isolates (3.8%) had virulent capsular serotypes, with K2 being the most prevalent 40% (n = 4) and K20 in 30% (n = 3). Furthermore, we detected the presence of the Aerobactin gene in 1.5% (n = 4) of the isolates examined. Based on our findings, it appears that there was no correlation between the presence of virulence factors and carbapenem resistance. In conclusion, identifying hypervirulent K. pneumoniae in clinical specimens and assessing their antibiotic resistance profiles are crucial to ensure effective therapy and to prevent outbreaks. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii and Pseudomonas aeruginosa are two pathogens with an important power of adaptation to antibiotics thus, both pose a real public health problem. Our study investigated epidemiological characteristics, antibiotic sensitivity profile and resistance genes of imipenem resistant A. baumannii and P. aeruginosa. This was a retrospective study carried out in the bacteriology laboratory of Mohammed V military training hospital, spanning from January 2018 to April 2021. Antibiotic susceptibility was studied by Mueller Hilton agar diffusion method with OXOID® type antibiotic discs and interpreted according to the recommendations of EUCAST 2021. Carbapenemase detection was performed by CarbaNP-test®. The molecular study was performed using conventional PCR. During the study period, we collected 1,072 imipenem-resistant isolates namely, 820 A. baumannii and 252 P. aeruginosa. The molecular study showed that out of 108 A. baumannii isolates 102 carried the bla OXA-51 and 100 isolates carried the bla OXA-23 gene. The coexistence of bla OXA-23 and bla NDM genes was detected in only 4 isolates. Altogether 50% of P. aeruginosa strains carried bla VIM-2. All investigated A. baumannii and P. aeruginosa strains were colistin susceptible in this study. Multiresistant bacterial infections are associated with longer hospitalization, higher hospital costs and higher mortality rates. Therefore, a collective action including the different actors of the healthcare system is necessary. [ABSTRACT FROM AUTHOR]

Over a 4-year study period from 2015 to 2018, altogether 183 isolates of bacterial meningitis were collected from 12 hospitals covering the entire Moroccan territory. Neisseria meningitidis represented 58.5%, Streptococcus pneumoniae 35.5%, and Haemophilus influenzae type b 6%. H. influenzae type b mainly affected 5-year-olds and unvaccinated adults. N. meningitidis serogroup B represented 90.7% followed by serogroup W135 with 6.5%. Decreased susceptibility to penicillin G (DSPG) for all isolates accounted for 15.7%, with 11.6% being resistant to penicillin G (PG) and 4.1% decreased susceptibility. Cumulative results of all strains showed 2.7% decreased susceptibility to amoxicillin and 3.3% resistant, 2.2% of isolates were resistant to third-generation cephalosporin and 2.2% were decreased susceptible, 5.5% were resistant to chloramphenicol and 2.7% were resistant to rifampin. The frequency of DSPG observed in our study is more common in S. pneumoniae than in N. meningitidis (P < 0.05). These isolates have been found to be highly susceptible to antibiotics used for treatment and prophylaxis chemotherapy and the observed resistance remains rare. The impact of introduction of conjugate vaccines against H. influenzae type b and S. pneumoniae (PCVs) is an advantage in reducing meningitis cases due to these two species. [ABSTRACT FROM AUTHOR]

Introduction: Bacteremia is responsible for high rates of morbidity and mortality. The increasing prevalence of multidrug-resistant (MDR) bacteria in intensive care units (ICU) is a growing concern. Hence, prior knowledge of bacterial epidemiology and resistance phenotypes is required to optimize these infections' management. The objective of this study was to determine the epidemiological profile of bacteremia in ICU settings, as well as the place occupied by MDR bacteria in these infections., Methods: It is a prospective study carried out over 10 months on episodes of bacteremia in the ICU of Mohammed V Military Teaching Hospital (Rabat, Morocco). Microorganism growth was detected using fluorescent technology, species identification was based on morphological and biochemical characteristics. Antimicrobial susceptibility testing was performed following the recommendations of the Antibiogram Committee of the French Society of Microbiology (CA-SFM) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST)., Results: Among 504 hospitalized patients, sixty-one (12.1%) presented at least one episode of bacteremia. Forty patients (65.6% of bacteremic patients) presented at least one episode of bacteremia due to MDR bacteria. Male gender, cardiovascular diseases, diabetes and previous hospitalization were significant risk factors for the acquisition of MDR bacteremia. Isolated bacteria were mainly Gram-negative bacilli (GNB) (n = 62; 68.9%) dominated by Acinetobacter baumannii (n = 19; 21.1%) and Klebsiella pneumoniae (n = 16; 17.8%). MDR bacteria were represented by multi-resistant Acinetobacter baumannii (n = 19; 44.2%), extended-spectrum beta-lactamases-producing Enterobacterales (n = 9; 20.9%) and carbapenem-resistant Enterobacterales (n = 7; 16.3%). Carbapenems (n = 40; 65.6%), Aminoglycosides (n = 32; 52.5%) and Polypeptides (n = 24; 39.3%) were the most used antimicrobials. Mortality rates were 66.6% (n = 40) and 85% (n = 43) in patients with non MDR bacteremia and MDR bacteremia respectively., Conclusion: Limiting the spread of MDR bacteria and improving the management of bacteremic patients require continuous monitoring of bacteremia as well as adapting the therapeutic and preventive strategy.