Prevalence and antimicrobial sensitivity of Shiga-toxin-producing Escherichia coli among underfives presenting with diarrhoea at hospitals in Mwanza City, Tanzania

Abstract

Background: Escherichia coli is among the most common causes of diarrhoea in children below five years of age in developing countries. Diarrhoeal diseases rank the second most common cause of morbidity and mortality in developing countries. Here we report the magnitude of Shiga toxin-producing Escherichia coli (STEC) infection among underfives with diarrhoea in Mwanza, Tanzania.

Methods: This study was carried out at Nyamagana and Sekou Toure hospitals in Mwanza, Tanzania. Between July, 2015 and March, 2016, children aged < 5 years with diarrhoea were included in the study. Demographics and relevant information were recorded. Stool specimens were cultured onto MacConkey and Salmonella-Shigella Agars. CHROMagar STEC was used to identify STEC. Antimicrobial susceptibility testing was performed to all pathogenic bacteria using disc diffusion method.

Results: A total of 304 children were include in the study. The mean (±standard deviation) age of the enrolled children was 1.4 (±1.03) years. Out of 304 diarrhoea cases, 32 (10.5%) were positive for STEC and 12 (3.9%) were due to other pathogenic bacteria (Salmonella and Shigella species.). Of 32 STEC isolates, 22 (68.8%) and 20 (62.5%) were resistant to amoxicillin/clavulanic acid and trimethoprim-sulfamethoxazole respectively and 3 (9.4%) were found to produce extended spectrum beta lactamases (ESBL). Use of water from wells (p=0.006) was found to be the predictor of the presence of pathogenic bacteria.

Conclusion: Clinicians should consider STEC as the potential pathogens causing diarrhoea in the region. More than 60% of pathogenic bacteria were resistant to commonly prescribed antimicrobials like amoxicillin/clavulanic acid and trimethoprim-sulfamethoxazole. There is a need to emphasize on the provision of safe water, health education together with improvements in sanitation and personal hygiene as key strategies to reduce these infections.