Objective This cross-sectional study aims to determine the prevalence and associated risk factors of biofilm-producing A. baumannii nosocomial isolates from a tertiary care hospital, as well as to investigate any possible association of biofilm formation with the distribution of biofilm-related genotypes and antibiotic resistance phenotypes. Methods A total of 94 non-duplicate A. baumannii nosocomial isolates were identified, their biofilm formation was quantitatively detected using the modified microtiter plate assay, and their susceptibilities to different antibiotics were determined using the breakpoint method. Isolates were then subjected to PCR assays targeting bap, omp A and bla PER-1 genes. Results The majority (70.1%) of isolates were biofilm producers. The most prevalent biofilm gene was omp A (63.8%), followed by bap (13.8%) and bla PER-1 (10.6%). The presence of multi- and extensive-drug resistance (MDR and XDR) was significantly associated with biofilm producers (p = 0.017 and 0.002, respectively). The length of hospital stay (aOR= 0.023), the presence of omp A gene (aOR = 0.286) or bap gene (aOR = 0.346), ampicillin/sulbactam resistance (aOR = 1), and the presence of MDR (aOR = −0.329) or XDR (aOR = −0.252) were considered significant risk factors associated with biofilm-producing isolates. Conclusion The high prevalence of biofilm-producing MDR and XDR nosocomial isolates in this study is worrisome and alarming. Characterization of risk factors could help control the continuous selection and transfer of this serious A. baumannii phenotype inside hospitals and improve the quality of patients’ care.

Background: Colistin is the last treatment option for infections caused by carbapenem resistant Gram-negative bacilli (CRGNB). The increasing spread of chromosomally encoded and plasmid-mediated colistin resistance made colistin susceptibility assessment a necessity. Objectives: Assessment of colistin susceptibility in CRGNB by broth micro dilution method (BMD), as the standard method and colistin broth disk elution method (CBDE), as a substitute procedure with genotypic determination of plasmid mediated colistin resistance (mcr) genes. Methodology: CRGNB were collected and identified by conventional methods. Testing carbapenemase production by modified Carbapenem Inactivation Method (mCIM) and colistin susceptibility (by BMD and CBDE) were done and results were interpreted regarding CLSI ( 2022) guidelines followed by genotypic detection of mcr-1, -2, -3, -4, and -5 genes by multiplex PCR. Results: 155 out of 308 GNB (50.3%) were carbapenem resistant. Among them, 129 (83.2%) isolates were carbapenemase positive by mCIM. Colistin susceptibility testing by BMD revealed 43 out of 155 CRGNB isolates (27.7%) were colistin resistant. Sensitivity, specificity, PPV, NPV and accuracy of CBDE were 99.09%, 93.33%, 97.32% 97.67%, 97.42% respectively with almost perfect agreement with BMD. By PCR, only 3 CRGNB isolates (6.98%) carried mcr-1 while other mcr genes were not detected at all. Conclusion: Colistin resistance rate among CRGNB is concerning, causing serious and even deadly infections so prospective surveillance is essential. Broth disk elusion method is a simple, non-expensive reliable option to test colistin susceptibility.

Background: Neonatal sepsis (NS) due to K. pneumoniae is a major cause of morbidity and mortality in neonates. This study aimed to study the risk factors of NS caused by K.pneumoniae in NICU in Menoufia University Hospitals and to detect rmpA and magA virulence genes and CTX-M antibiotic resistance gene. Correlation between compliance of infection control measures and occurrence of NS and its outcome were also evaluated. Methods: Klebsiella pneumoniae were isolated from blood of neonates with sepsis and studied for hypermucovicosity by string test and detection of rmpA and magA genes. ESβL production was studied by cephalosporin/clavulanate combination disks and expression of CTX-M gene groups. Hand hygiene and other infection control measures compliance were evaluated by observational and practical methods. Results: Klebsiella pneumoniae was the most frequently isolated organism (31.6%) among neonates with confirmed sepsis. Hypermucoviscous phenotype was detected by string test in 39.6% of isolates while rmpA and magA genes were found in 47.9% and 8.3% respectively. ESβL production was confirmed in 75% (by cephalosporin/clavulanate combination disk). The CTX-M gene was found among 77.8% of ESβL-producing K. pneumoniae isolates. There was a negative correlation between hand hygiene and other infection control measures compliance and occurrence of NS. Conclusion: Virulence and antimicrobial resistance genes are common among K. pneumoniae isolated from neonates with sepsis in our locality. Implementation of infection control measures and proper antimicrobial stewardship programs may be helpful to overcome this problem..

Background: Treatment response to antiviral drugs is a challenging issue in patients with chronic hepatitis C virus (HCV) infection. Although microRNA-122 represents the majority of the microRNA content in hepatic tissues, few studies have evaluated its role in the treatment response, so we aimed to study its role in chronic HCV patients and in predicting the treatment response to direct-acting antivirals (DAAs). Methods: The study included 125 chronic HCV patients (89 naïve and 36 with a prior failed peginterferon/ribavirin response) and 50 apparently healthy subjects. Complete blood count, liver function, α-fetoprotein, lipid profiles, serum creatinine, abdominal ultrasound, and FibroScan ® were assessed. Viral markers, HCV antibodies, and hepatitis B surface antigen were measured by enzyme-linked fluorescent immunoassay, with quantitative estimation of HCV RNA and microRNA-122 levels by real-time PCR. Results: The microRNA-122 level in HCV patients (those with a sustained virologic response 12 weeks after finishing therapy [SVR12] and non-responders) was significantly increased compared with controls and expressed more in non-responders versus SVR12 (p=0.042). ROC curve analysis of microRNA-122 for differentiating HCV patients from healthy controls revealed that a cutoff point of >1.45 had a sensitivity of 67.20%, specificity of 94.0%, AUC=0.861, and p<0.001; and for predicting response to treatment a cutoff point ≤5.66 could significantly (p=0.022) predict the occurrence of SVR, with a sensitivity of 60.34%, specificity of 66.67%, and AUC=0.729. Logistic regression analysis showed significant values for microRNA-122 in multivariate and univariate analysis for the prediction of response to DAAs. Conclusion: The results demonstrated the possible function of microRNA-122 as an indicative tool for distinguishing chronic HCV patients from controls and in the assessment of the therapeutic reaction to DAAs.

Background: Carbapenemases production by extended-spectrum β-lactamases (ESβLs)- producing Escherichia coli (E. coli) has been increasingly found and may be considered as a major cause of morbidity and mortality in hospital-acquired infection. Objectives: To determine resistance pattern and frequency of carbapenem resistance and presence of class D carbapenemases among ESβLs-producing E. coli isolated from patients in Menoufia University Hospitals. Methodology: Different clinical samples were obtained from 270 patients who were admitted to Menoufia University Hospitals. E. coli were isolated and identified, and their antimicrobial resistance profiles were tested by the disk diffusion and agar dilution methods. Confirmed ESβLs producers (by cephalosporin/ clavulanate combination disks and ESβL NDP tests) were further tested for carbapenemase production by phenotypic and genotypic methods. Results: E. coli was the most common isolate (30.4%) from clinical samples. High rate of ESβLs-producing E. coli was detected by disk diffusion (87.5%), cephalosporin/clavulanate combination disk (62.5%) and ESβL NDP test (60%).About10%, 24% and 28% of the ESβLsproducing E. coli isolates were producers of class A, B and D carbapenemases respectively. The prevalence of blashv, blaoxa23 and blaoxa48 genes among ESβLsproducing E. coli isolates was 18%, 22% and 12% respectively. Conclusion: Carbapenemases production by EβSLs-producing E. coli is a major challenge. A great concern should be paid to provide alternative new therapeutic agents, continuous surveillance, and effective antibiotic stewardship program.

Background: Staphylococcus aureus (S. aureus) is a world-wide nosocomial and community-acquired infectious agent. This study aimed to determine the prevalence rate of S. aureus infections with assessment of their antibiotic susceptibility patterns and virulence profiles using available phenotypic and genotypic methods. Methodology: Staphylococcus aureus isolates were collected and identified by conventional methods. Antimicrobial susceptibility testing was done and interpreted according to Clinical and Laboratory Standards Institute guidelines (2022) followed by macrolide lincosamide streptogramin B (MLSB) phenotyping by D test. Detection of staphylococcal virulence (hla and etb) and antibiotic resistance (ermB and msrA) genes were also done. Results: Out of 152 S. aureus isolates, 84 (55.3%) and 68 (44.7%) were methicillin resistant (MRSA) and methicillin susceptible S. aureus (MSSA) respectively. Almost all MRSA isolates were beta hemolytic and susceptible to linezolid, streptogramins (100% for each) vancomycin (95.2%) and ceftaroline (90.5%). About 84.5% and 45.2% of MRSA compared to 36.8% and 27.9% of MSSA were resistant to erythromycin and clindamycin respectively. Regarding MLSB phenotyping 44%, 9.5% and 31% of MRSA and 28.1%, 1.5% and 10.3% of MSSA were constitutive cMLSB, inducible iMLSB and MSB phenotypes respectively. hla, erm B and msrA genes were detected in 91.7%, 10.7% and 1.2% of MRSA isolates respectively. While etb gene was not detected at all among them. Conclusion: Methicillin and MLSB resistance among S. aureus are concerning. Therefore, great efforts should be made for their accurate detection in hospital settings. Proper antibiotic stewardship program is strongly recommended to keep the benefit of antibiotics with acceptable susceptibility pattern.

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There is a possible link between exposure to Triclosan (TCS) and changes in antimicrobial susceptibility. The change in the tolerance of clinical Escherichia coli (n=45) isolates to the biocide TCS, changes in antibiotic resistance and differences in the efflux pump mechanism were analyzed. 45 E. coli isolates were obtained. The minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) of TCS, and the expression of four efflux pump encoding genes in antibiotic-resistant isolates were determined before and after TCS adaptation. The number of TCS-tolerant isolates was 11 (24.4%). After adaptation, the percentage of tolerant isolates increased to 42.2% (n=19). A significant change (p<0.05) in antimicrobial resistance of the tested isolates (n=45) before and after TCS adaptation was detected for ceftazidime, ceftriaxone, ertapenem, imipenem, amikacin, gentamicin, tobramycin, ciprofloxacin, levofloxacin and doxycycline. Among the new TCS tolerant isolates (n=8). there was an increase in TCS MIC as well as the MBC after TSC adaptation. The adapted isolates exhibited a significant increase in the expression of mdfA and norE genes (p=<0.001). There is a strong correlation between efflux pump gene overexpression and susceptibility to TCS and other antimicrobials.