Genetic Determinants of Antibiotic Resistance in Hospital and Community Isolates of Klebsiella pneumoniae and Escherichia coli

Background Multi-drug resistant Escherichia coli and Klebsiella pneumoniae with various resistance determinants are a major concern in hospital and community acquired infections around the world. Objectives To describe the presence of bla_CTX-M, bla_TEM, bla_PER, bla_VEB, and integrons class 1, 2, 3 and extended spectrum β lactamase (ESBL) phenotype in E. coli and K. pneumoniae isolates from clinical samples of inpatients and outpatients. Methods One hundred and eighty six E. coli and fifty-eight K. pneumoniae were collected. Antimicrobial susceptibility test was performed by disk diffusion method. Extended-spectrum beta-lactamase phenotype were screened by phenotypic confirmatory test. PCR assay was performed for bla_TEM, bla_CTX-M, bla_PER and bla_VEB and class 1, 2, 3 integrase genes. Statistical analysis was performed by chi-squared test. Results Extended-spectrum beta-lactamase phenotype was detected in 49 (26.3%) E. coli and 19 (32.8%) K. pneumoniae isolates. Bla_VEB gene in 32 (17.2%) E. coli and 5 (8.6%) K. pneumoniae isolates. Bla_PER gene in 4 (2.1%) E. coli and 0 (0%) K. pneumoniae isolates. Bla_CTX-M gene in 113 (60.7%) E. coli and 34 (58.6%) K. pneumoniae isolates. Bla_TEM gene in 106 (57%) E. coli and 25 (43.1%) K. pneumoniae isolates. One hundred and nine (58.6%) of E. coli and 33 (56.9%) of K. pneumoniae were carrying Class 1 integron and 18 (9.7%) of E. coli and 3 (5.2%) of K. pneumoniae were carrying Class 2 integron. Class 3 integron was not detected. Conclusions High prevalence of ESBLs in E. coli and K. pneumoniae isolated from the community and hospital acquired infections could lead to the wide spread of multi-drug resistance clones that also contain new mechanism of resistance.