Genotypic Determination of Extended Spectrum ß-Lactamases and Carbapenemase Production in Clinical Isolates of Klebsiella pneumoniae in Southwest Nigeria.

INTRODUCTION: Klebsiella pneumoniae is a major pathogen implicated in healthcare-associated infections. Extended-spectrum ß-lactamase (ESBL) and carbapenemase-producing K. pneumoniae isolates are a public health concern. This study investigated the existence of some ESBL and carbapenemase genes among clinical isolates of K. pneumoniae in Southwest Nigeria and additionally determined their circulating clones. MATERIALS AND METHODS: Various clinical samples from 420 patients from seven tertiary hospitals within Southwestern Nigeria were processed between February 2018 and July 2019. These samples were cultured on blood agar and MacConkey agar, and the isolated bacteria were identified by Microbact GNB 12E. All K. pneumoniae were confirmed by polymerase chain reaction (PCR) using the 16s rRNA gene. Antibiotic susceptibility testing (AST) was done on these isolates, and the PCR was used to evaluate the common ESBL-encoding genes and carbapenem resistance genes. Genotyping was performed using multi-locus sequencing typing (MLST). RESULTS: The overall prevalence of K. pneumoniae in Southwestern Nigeria was 30.5%. The AST revealed high resistance rates to tetracyclines (67.2%), oxacillin (61.7%), ampicillin (60.2%), ciprofloxacin (58.6%), chloramphenicol (56.3%), and lowest resistance to meropenem (43.0%). All isolates were susceptible to polymyxin B. The most prevalent ESBL gene was the TEM gene (47.7%), followed by CTX-M (43.8%), SHV (39.8%), OXA (27.3%), CTX-M-15 (19.5%), CTX-M-2 (11.1%), and CTX-M-9 (10.9%). Among the carbapenemase genes studied, the VIM gene (43.0%) was most detected, followed by OXA-48 (28.9%), IMP (22.7%), NDM (17.2%), KPC (13.3%), CMY (11.7%), and FOX (9.4%). GIM and SPM genes were not detected. MLST identified six different sequence types (STs) in this study. The most dominant ST was ST307 (50%, 5/10), while ST258, ST11, ST147, ST15, and ST321 had (10%, 1/10) each. CONCLUSION: High antimicrobial resistance in K. pneumoniae is a clear and present danger for managing infections in Nigeria. Additionally, the dominance of a successful international ST307 clone highlights the importance of ensuring that genomic surveillance remains a priority in the hospital environment in Nigeria.

Detection of Antibiotic Resistance Genes Among Multiple Drug Resistant Pseudomonas Aeruginosa Isolated from Clinical Sources in Selected Health Institutions in Kwara State.

BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa) is a frequent nosocomial pathogen that causes severe diseases in many clinical and community settings. Strains of P. aeruginosa are associated with increased morbidity, mortality and healthcare costs. The rapid emergence of antimicrobial resistance among these strains is a public health crisis. Moreover, there is a paucity of data on the characterization of P. aeruginosa isolates from human clinical samples in Kwara State. OBJECTIVES: The objectives of this study are to investigate the occurrence of metallo ß-lactamase enzyme, multiple antibiotic resistant P. aeruginosa among clinical samples and detection of antibiotic resistance genes among them. METHODS: Two hundred and thirty-five samples comprising of 145 males and 90 females human clinical specimens were collected aseptically from five selected health institutions within Kwara State, Nigeria. The samples were cultured immediately using standard microbiological procedures. Multiple drug resistance patterns of the micro-organisms to different antibiotics were determined using the Bauer Kirby disc diffusion technique. Metallo ß-lactamase production was determined using E - test strip and the DNA samples of the multiple resistant P. aeruginosa strains were extracted and subjected to Polymerase Chain Reaction (PCR) for resistant genes determination. Data were subjected to descriptive statistics using Statistical Package for Social Sciences (SPSS) software. RESULTS: A total of 145 isolates were identified for P. aeruginosa from the clinical samples. Thirty were positive for metallo ß-lactamase production; 11 (8%) males and 19 (13%) females. Absolute resistance to ceftazidime (100%), gentamicin (100%), ceftriaxone (100%) were observed while low resistance to ciprofloxacin (12.4%), piperacillin (6.9%) and imipenem (6.9%). All isolates were sensitive to colistin. The prevalence of various encoding genes blaVIM, , blaCTX-M and blaTEM were 34.4%, 46.7%, 16.7% and 37.7% respectively. CONCLUSION: This study has shown that there is a high occurrence of metallo ß-lactamase enzyme producing and antibiotic-resistant strains of P. aeruginosa in clinical specimens from the studied area. Necessary measures must, therefore be implemented to stop the problems of this antibiotic resistance.

Seroprevalence of HIV, HBV, HCV, and HTLV among Pregnant Women in Southwestern Nigeria.

Sexually transmitted infections (STIs) are major public health challenge especially in developing countries. This study was designed to determine the prevalence of Hepatitis B virus (HBV), Hepatitis C Virus (HCV), Human immunodeficiency virus (HIV), and Human T-cell lymphotropic Virus type I (HTLV-I) among pregnant women attending antenatal clinic, in Ladoke Akintola University Teaching Hospital, Osogbo, and South-Western Nigeria. One hundred and eighty two randomly selected pregnant women were screened for HBsAg, anti-HCV, anti-HIV and HTLV-1 IgM antibodies using commercially available ELISA kit. Of the 182 blood samples of pregnant women screened whose age ranged from 15-49 years, 13 (7.1%), 5 (2.7%), 9 (4.9%), and 44 (24.2%) were positive for HBsAg, anti-HCV, anti-HIV, and HTLV-1 IgM antibodies, respectively. The co-infection rate of 0.5% was obtained for HBV/HCV, HBV/HIV, HIV/HTLV-1, and HCV/HTLV-1 while 1.1% and 0% was recorded for HBV/HTLV-1 and HCV/HIV co-infections, respectively. Expected risk factors such as history of surgery, circumcision, tattooing and incision showed no significant association with any of the viral STIs (P > 0.05). This study shows that there is the need for a comprehensive screening of all pregnant women for HBsAg, anti-HCV, anti-HIV and HTLV-1 to prevent mother to child transmission of these viral infections and its attending consequences.

Phenotypic and Molecular Characterisation of Extended-Spectrum Beta-Lactamase Producing Escherichia coli Obtained from Animal Fecal Samples in Ado Ekiti, Nigeria.

Production of extended-spectrum ß-lactamases (ESBLs) producing E. coli in animals and different methods of identifications from Ado Ekiti, Ekiti State, Nigeria, were investigated. Three hundred and fifty fecal samples, collected from apparently healthy cattle and pigs, were cultured and identified following standard procedures. ESBL phenotypic detection was carried out using combination disc test, double disc synergism test, and ESBL brilliance agar screening. Molecular detection of TEM, SHV, and CTX-M genes was carried out using standard molecular method. One hundred and fourteen E. coli isolates were recovered from the 350 samples processed, out of which 72 (63.2%) isolates were positive for ESBLs with multiple resistance to the antibiotics used. Eighty-one (71%) isolates were positive for ESBL by combination disc test, 90 (78.9%) were positive for double disc synergism test, and 93 (81.6%) were positive for ESBL brilliance agar. TEM and CTX-M genes were detected in 48 (42.1%) and 51 (44.7%) isolates, respectively. SHV gene was not detected in any of the isolates while TEM and CTX-M were detected in 33 (28.9%) isolates. This study showed high resistance of E. coli to antibiotics, particularly to the third generation cephalosporins. Regular monitoring and regulated use of antibiotics in livestock should be encouraged.