BackgroundThe staphylococci have increasingly been associated with infections worldwide and anti-microbial resistance has made these versatile pathogens more recalcitrant in the hospital setting.ObjectivesThis study sought to investigate the occurrence and distribution of Staphylococcus species as well as determine the prevalence of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative staphylococci (MRCoNS) among clinical samples from University of Benin Teaching Hospital (UBTH) in Benin City.MethodsNinety one (91) clinical isolates comprising S. aureus and Coagulase Negative staphylococci (CoNS) were recovered from routine clinical specimens and anti-microbial susceptibility tests were carried out. Polymerase Chain Reaction (PCR) was thereafter carried out on these isolates to detect mecA gene.ResultsStaphylococcus species had its highest prevalence from infected wounds of patients (28.8%) while urine samples showed the least (5.4%). The highest level of resistance was to ceftazidime (S. aureus - 68%, CoNS - 75.6%) while the least resistance was observed for meropenem (S. aureus- 26%, CoNS- 46.3%). Using phenotypic method (with 1µg oxacillin antibiotic disc), the distribution of MRSA and MRCoNS was 44.0% and 46.3% respectively. PCR analysis showed that 38.0% of S. aureus and 41.5% of the CoNS had mecA gene respectively; wound swabs showed the highest prevalence with 30.5% of staphylococcal isolates being mecA gene positive. There was also no significant association between the Staphylococcal isolates and their isolation rate, isolation site and mecA gene distribution (p > 0.05).ConclusionThis study draws attention on the increase in the prevalence of mecA gene (39.6%) and an increase in multidrug resistant staphylococci when compared to previous studies in our country; it recommends laboratory guidance and periodic review to stem the tide of resistance.

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This study was carried out to determine the prevalence of extended spectrum beta-lactamase (ESBL) among Gram negative bacteria isolated from cattle feces in Benin City, Nigeria. A total of 250 Gram negative bacteria isolates were recovered from cattle feces and were processed microbiologically using standard techniques. Emergent colonies were identified and antibacterial susceptibility tests were determined using Kirby-Bauer disk diffusion method. All bacterial isolates were screened for the presence of ESBL using the double-disc synergy method. A total of 37 (14.8%) isolates were positive for ESBL, with 33 (13.2%) indicated by ceftazidime, while only 4 (1.6%) were indicated by both ceftazidime and cefotaxime (P < 0.0001). Of the Gram negative bacterial isolates recovered, Salmonella species was the most prevalent ESBL-producer with 55.0% prevalence (P = 0.0092), while no isolate of Pseudomonas aeruginosa produced ESBL. ESBL-positive isolates showed poor susceptibility to the tested antibacterial agents in comparison with non-ESBL-producers and imipenem was the most active antibiotic. The prevalence of ESBL among Gram negative bacilli recovered from cattle feces was 14.8%. The study advises prudent use of antibiotics in the treatment of cattle and harps on improved hygiene in managing cattle, as they are potential reservoirs of ESBL-producing organisms.

The emergence of HIV has reawakened the tuberculosis (TB) scourge and infected patients are prone to opportunistic infections, this study was carried out to determine the HIV status and etiologic agents of Lower respiratory tract infections (LRTI) among tuberculosis suspected patients in Benin City, Nigeria. The study was cross sectional. A total of 276 patients attending tuberculosis clinic were recruited. Questionnaires were filled for each patient. Blood and sputum specimens were collected in plain and sterile containers respectively and transported immediately to the laboratory. Blood samples were screened for the presence of HIV antibodies. The sputum specimens were then cultured following standard microbiological procedure, and thereafter processed using the GeneXpert MTB/RIF assay. Emergent bacterial colonies were identified and susceptibility testing was carried out following standard microbiological techniques. A total of 118 (42.8%) non-mycobacterial bacterial agents were recovered from the patients. Patients were more likely to be culture positive for LRTI in comparison with TB infection (p < 0.0001). There was no association between TB and HIV status (OR = 0.6161, 95%CI = 0.226, 1.648, p = 0.4474). HIV positive patients were more likely to be culture positive for bacterial agents and Klebsiella pneumoniae was more likely to be recovered (p = 0.0338). The fluoroquinolones, gentamicin and ceftriaxone-sulbactam were the most active antibacterial agents against bacterial isolates. The prevalence of LRTI in this study was 52.2%. The study draws attention on the need for physicians to request for bacteriological culture (non-mycobacterial) alongside the TB diagnostic algorithm in suspected TB cases.

Background<br />Multi-drug resistant bacterial strains have been increasingly implicated in clinical infections worldwide and beta-lactamase production is one of the commonest mechanisms of resistance in these strains. This study investigated the prevalence of extended spectrum â-lactamase (ESBL)-producing isolates and determined the temoneira (TEM) and sulfhydryl variable (SHV) types implicated in two military hospitals in South-South Nigeria. <br /><br />Methods<br />Three-hundred and eighty (380) consecutive non-duplicate bacterial isolates (Gram negative bacilli) recovered from clinical samples were identified following standard techniques. Antimicrobial susceptibility tests were performed for each isolate following the Clinical Laboratory Standards Institute guidelines. Bacterial isolates recovered which comprised Escherichia coli, Klebsiella spp, Proteus spp and Pseudomonas aeruginosa were screened for ESBL using a phenotypic method (double disc synergy test). All positive isolates were screened for TEM and SHV genes by PCR method. <br /><br />Results<br />Sixty-five isolates (17.1%) were ESBL producing using phenotypic method, E. coli showed the highest ESBL prevalence (24.3%). One isolate was SHV positive (1.5%), 8 (12.3%) were TEM positive while 3 (4.6%) isolates harbored both SHV and TEM genes. Fluoroquinolone - ofloxacin showed marked activity against ESBL-producing isolates (90.8%) while the least active were ceftriaxone (9.2%), ceftazidime (3.1%) and ampicillin (1.5%). <br /><br />Conclusion<br />This study demonstrated that 17.1% of Gram-negative bacilli were ESBL producers. Screening of clinical isolates for ESBL should be implemented. The findings of this study suggest the need for caution in the use of antimicrobial agents in order to curb the incidence of antimicrobial resistance.