Prevalence of Multidrug Resistant Escherichia coli O157:H7 Causing Diarrhoea in Children at District Khairpur

Aim: Multidrug resistance (MDR) is a major public health problem worldwide. The aim of this study was to assess the prevalence, levels of antimicrobial susceptibility and extended-spectrum beta lactamase (ESBL) production by Escherichia coli O157: H7.

Methodology: A cross sectional study was performed and a total of 116 stool samples were collected from children aged ≤ 5 years presenting diarrhoea from hospital located at district Khairpur. E. coli O157: H7 was isolated on Sorbitol MacConkey agar and isolates were initially characterized by Gram staining. Subsequently biochemical characteristics except oxidase test (which was performed manually) and drug sensitivity test was performed by using Automated MicroScan® walkaway machine. ESBL production by isolates was determined by disc diffusion method as per Clinical & Laboratory Standards Institute (CLSI) guidelines.

Results: Out of 116 diarrheal samples tested, 16 (13.79%) samples were positive for E. coli O157:H7. High number of E. coli O157: H7 were isolated from children aged up to 1 year followed by 2-3 years aged. Isolates were frequently found in summer season (12 times) followed by winter (3 times) and Autumn (1 time). The isolates were found 100% resistant against Nalidixic acid, Imipenem, Amoxycillin /Clavulanic Acid, Norfloxacin, Chloramphenicol, Vancomycin, Doxycycline, and Ampicillin and 90% resistant to Cifixime. ESBL production was noted in 12 (75%) out of 16 E. coli O157:H7 isolates as confirmed by CLSI protocol.

Conclusion: This study revealed that E. coli O157: H7 should be considered as major pathogenic bacterium causing diarrhea in children less than three years. The prevalence of ESBL producer MDR E. coli O157: H7 is of great concern, which requires monitoring of infection control measures through efficient antimicrobial management to ensure an uncompromised public health.