Prevalence and Antibiogram Profile of Carbapenem-resistant Escherichia coli and Klebsiella pneumoniae among Patients with Urinary Tract Infection in Abakaliki, Nigeria

Background and Objectives: Carbapenem antibiotic are drug of last-resort from the treatment of bacterial infection, as a result of the prevalence and rapidly evolving enzymes from Carbapenem resistant bacteria such Escherichia coli and Klebsiella pneumoniae make urinary tract infection difficult, and in some cases impossible to treat in health care settings. With limited progress of new antibacterial drugs, the best approach is monitoring the prevalence and antibiogram profile of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae among patients with UTI in Abakaliki, Nigeria.

Methodology: A non-repetitive, clean catch mid-stream urine was collected from five hundred (500) diagnosed UTI inpatient and outpatient. The samples were evaluated using routine microbiological protocol for isolation and identification of Escherichia coli and Klebsiella pneumoniae. Phenotypic screening of Carbapenem-resistant strains was performed using Modified Hodge Testing. Antibiogram studies of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae was performed using the Kirby–Bauer disk diffusion method and the results were interpreted using the Clinical Laboratory Standard Institute (CLSI) zone diameter breakpoints. Multiple antibiotic resistance index (MARI) was determined for MDR strain.

Result: The prevalence of Escherichia coli and Klebsiella pneumoniae isolate accounted for 148(29.6 %) consisting of 95(54.3 %) and 53(16.3 %) from in-patients and out-patients. Escherichia coli accounted overall isolation rate of 112(22.4 %) comprising of high proportion among in-patient 82(46.9 %) over out-patient 30(9.2 %). The proportion of K. pneumoniae accounted for 36(7.2 %) with 13(7.4 %) and 23(7.1 %) recorded among in-patients and out-patients. Association between presence of Escherichia coli and Klebsiella pneumoniae isolates in clinical samples was statistically significant with patient’s population with p value <0.05. Carbapenem-resistant Escherichia coli and Klebsiella pneumoniae accounted for 37(7.4 %) comprising of 24(13.7) and 13(4.0 %) among in-patients and out-patients respectively while carbapenem-susceptible Escherichia coli and Klebsiella pneumoniae accounted for overall detection rate of 111(22.2 %) consisting of 71(40.6 %) and 40(12.3 %) among in-patients and out-patients respectively. The isolates resistance rate to cephalosporins were relatively high i.e., Cefotaxime, Cefoxtin Ceftazidime, Ceftriaxone resistance was observed at 60-100% while amoxicillin/clavulanate, azetronam, tetracycline nitrofurantoin and Ticarcillin-clavulanic acid recorded 100 % with MDR index ranged from 0.5-0.8, but were 100 % and 85.0 % sensitive to ciprofloxacin and ofloxacin.

Conclusion: These results strongly hypothesize that MDR bacteria, including Carbapenem-resistant isolate, have become common residents in various hospital environments, however with substantial evidence in this study, ciprofloxacin and ofloxacin as drugs of choice could be used for treatment of UTI. Therefore, its importance that good antibiogram evaluation of other drug classes beside fluoroquinoles reported in this study need to be establishes as baseline for empirical diagnosis, epidemiological surveillance, drug prescriptions and infection management.