Abstract

The nosocomial infections associated with bacterial resistance are a public health problem in hospitals. The aim of the present study was to determine the antibiotic susceptibility patterns and distribution of the blaTEM, blaCTX M, blaSHV and blaOXA ESBL resistance genes in Escherichia coli and Klebsiella species isolated from specimen of patients suffering from nosocomial infections. This was a prospective study that included the results of specimen exahation, their corresponding antibiotic susceptibility testing, and the results of conventional polymerase chain reaction concerning the beta-lactamase genes of identified isolates. The study was conducted over a period of nine months, from January 2023 to September 2023. Eighty-four isolates with a phenotypic beta-lactamase profile were isolated from urine and pus specimens collected from patients suffering from nosocomial infections. Of the 84 isolates, Escherichia coli represented 83.33% and Klebsiella 16.67%. These bacteria were isolated from urine in 84.30 and 64.30% of cases for Escherichia coli and Klebsiella, respectively. The pathogens also showed a high level of resistance and co-resistance to the tested antibiotics. E. coli showed 100% resistance to amoxicillin, 100% to amoxicillin + clavulanic acid, 98.57% to ceftriaxone, and 94.29% to gentamicin but was sensitive to meropenem at 97.14%. Klebsiella isolates showed 100% resistance to amoxicillin + clavulanic acid, 75% to ceftriaxone, 91.67% to gentamicin, but were sensitive to meropenem at 91.66%. Concerning the beta-lactamase genes, the CTX-M 1 was the most prevalent in the isolates, ranging from 97.14 to 78.57% for E. coli and Klebsiella, respectively. Improving hospital hygiene and prescribing antibiotics appropriately after conducting antibiotic sensitivity tests are fundamental in the fight against nosocomial infections.

Key words: Extended-spectrum beta-lactamases genes, Escherichia coli, Klebsiella species, Niamey, nosocomial infections.