This study was conducted to study the prevalence of diarrheagenic Escherichia coli (DEC) in dysentery cases with special reference to Shiga-like toxin producing Escherichia coli (STEC).
During a two-year period, 1066 stool samples were collected from hospitalized patients with diarrhea and dysentery. After taking detailed clinical history and observing the gross and microscopic findings of the stool samples, they were cultured on MacConkey and Sorbitol MacConkey agars and E.coli isolates were identified by standard biochemical tests.
Of the 100 E.coli strains isolated in pure culture and sent for sero typing to Central Research Institute (CRI), Kasauli, 43% were found to be DEC, giving an isolation rate of 4.03%. Results of sero typing showed 37.21% STEC which were more common in children. Abdominal pain and stool with mucus flakes were statistically significant parameters (p less than 0.01) in patients with dysentery due to E.coli strains. Though E.coli O157 was not encountered, it was seen that 25% of STEC did not ferment sorbitol. The DEC strains showed maximum in vitro sensitivity to amikacin (83.72%) and all strains were resistant to nalidixic acid. Antibiotics along with ORS and intravenous fluids had to be given in 68.42% patients. As complications, about 16.67% of children developed hemolytic uremic syndrome (HUS),and 10.53% of patients developed acute renal failure. No mortality was reported.
Though Enterohemorrhagic E.coli (EHEC) O157:H7 was not encountered in this study, STEC caused by E.coli non O157 was reported. STEC is also known to cause hemorrhagic colitis (HC) and HUS. In this study HUS was reported in 16.67% children. Therefore, proper isolation and identification of STEC is essential in a tertiary care centre, to initiate prompt management and reduce morbidity and mortality in children.