Molecular detection and antibiotic resistance pattern of extended-spectrum beta-lactamase producing Escherichia coli in a Tertiary Hospital in Enugu, Nigeria

Abstract

Background: The use of antibiotic agents in the treatment of infectious diseases has greatly contributed to the decrease in morbidity and mortality, but these great advances in treatment are being undermined by the rapidly increasing antimicrobial resistant organisms. Extended-spectrum beta-lactamases are enzymes hydrolyzing the beta lactam antibiotics, including third generation cephalosporins and monobactams but not cephamycins and carbapenems. They pose a serious global health threat and have become a challenge for health care providers. The aim of this research was to assess the prevalence of extended-spectrum beta-lactamase producing Escherichia coli in University of Nigeria Teaching Hospital Ituku-Ozalla Enugu and to detect the risk factors for acquisition of the resistant organism. To proffer advice on antibiotic stewardship in clinical practice and public health interventions, to curb the spread of the resistant organisms in the hospital. Results: Out of the 200 E. coli isolates, 70 (35.00%) were confirmed positive for extended-spectrum beta-lactamase production. Fifty-three (75.7%) were from hospital acquired infections. All the isolates were resistant to ampicillin, tetracycline and chloramphenicol while 68 (97.14%) of the 70 isolates were susceptible to imipenem. Bla TEM, bla SHV and bla TEM were detected in 66 (94%) of the 70 isolates. The ESBL bla genes detected were bla CTX-M (n = 26; 37.14%), bla TEM (n = 7; 10.00%), bla SHV (n = 2; 2.86%), bla CTX-M/TEM (n = 7; 10.0%), bla CTX-M/SHV (n = 14; 20.0%) and bla CTX-M/TEM/SHV (n = 10; 14.29%). The three bla genes were not detected in 4 (5.71%) of the isolates. Recent surgery, previous antibiotic and intensive care unit admission were the associated risk factors to infections caused by extended-spectrum beta-lactamase producing E. coli. Conclusion: There is a high rate of infections caused by extended-spectrum beta-lactamase producing E. coli. Recent surgery, previous antibiotic and intensive care unit admission were associated risk factors.