Incidence of Extended Spectrum β-Lactamase Genes (ESBLs) among community and health care infection in Mansoura University Hospital, Egypt.

Abstract

Background: Multidrug-resistant (MDR) Gram-negative bacteria pose a significant challenge due to their limited treatment options. The production of extended-spectrum β-lactamases (ESBLs) is an important mechanism of resistance. This study aimed to identify the incidence and characteristics of ESBL-encoding genes (bla_CTX-M, bla_TEM, bla_SHV, and bla_OXA) in MDR isolates.

Materials and methods: A cross-sectional study was conducted from September 2022 to May 2023. ESBL-producing isolates (n = 105) out of 412 were recovered from hospitalized and outpatient settings and analyzed. Standard microbiological methods were used for isolates identification, susceptibility testing, and phenotypic ESBL detection. Additionally, bla_CTX-M, bla_TEM, bla_SHV, and bla_OXA genes were identified using conventional PCR.

Results: Molecular profiling of β-lactamase determinants was conducted via PCR targeting bla_CTX-M, bla_TEM, bla_SHV, and bla_OXA genes. Among phenotypically confirmed (100%) ESBL producers, 98% harbored one or more target genes, with bla_CTX-M predominant (81%), followed by bla_SHV (70.4%), bla_TEM (62%), and bla_OXA (30.4%). Carbapenem resistance was higher in ESBL-producing strains compared to non-ESBL strains. Extensively drug-resistant (XDR) isolates were the most common across hospital departments and outpatients.

Discussion: This study highlights the significant prevalence of ESBL genes and multidrug resistance among Gram-negative bacteria. The dominance of bla_CTX-M and the existence of multiple resistance genes raise concerns about limited treatment options. The findings emphasize the need for stricter antibiotic stewardship and infection control measures to curb the spread of MDR pathogens.

Conclusion: This study provides valuable insights into the alarming incidence of ESBL genes and MDR in Mansoura, Egypt. Continuous surveillance and implementation of effective control strategies are crucial to combat this growing public health threat.