Phenotypic and genotypic screening of multidrug resistant Klebsiella pneumoniae isolated from ready to eat street food in Tanta, Egypt

Abstract

Background

Ready-To-Eat-Street-Foods (RTESF) have food safety concerns, since they are prepared with less-structured food safety guidelines in small and roadside outlets. Klebsiella pneumoniae has become a dangerous foodborne-pathogen worldwide due to its virulence and resistance profile.

Objective

This study aimed at evaluating the potential burden of antibiotic-resistant Klebsiella pneumoniae contaminating RTESF and assessing the microbiological quality of RTESF in Egypt.

Methods

A total of 242 RTESF (green salad) samples was collected, different media were used for isolation of different bacterial species. Klebsiella pneumoniae isolates were identified biochemically and by Gram and capsular staining then isolates were assessed for antimicrobial resistance phenotypically. The ability of biofilm formation was assessed using crystal violet and molecular characterization of ESBLs and virulence genes was done using PCR.

Results

A total of 77/242(31.8%) of the recovered isolates was identified as Klebsiella pneumoniaeand the resistance percentages were as follow: cefuroxime and cephradine (100%, 77/77), amoxicillin-clavulanic acid (98.7%, 76/77), while (27.3%, 21/77) of the isolates were MDR. Biofilm assay revealed that (31/77, 41/77 and 5/77) isolates were strong, moderate, and weak biofilm-producers, respectively. Among ESBLs-encoding-genes, bla_SHV was the most prevalent (71.4%) while bla_TEMand bla_CTX−M−2were equally-present (55.8%).The most prevalent virulence genes were mrkD (92.2%) followed by K2 (63.3%).

Conclusion

The contaminated RTESF could be a reservoir for Klebsiella pneumoniae, therefore much care must be taken during preparation and consumption to avoid dissemination of MDR Klebsiella pneumoniae leading to subsequent treatment challenges. Our finding indicating that RTESF, if not prepared under hygienic conditions, could be a source of serious Klebsiella pneumoniae infection.