Duration of fecal shedding of Shiga toxin-producing Escherichia coli among children with hemolytic uremic syndrome.

Introduction: Knowing the duration of fecal shedding of Shiga toxin-producing Escherichia coli (STEC) among patients with hemolytic uremic syndrome would be useful to control disease transmission.

Objectives: 1) To analyze the characteristics of STEC shedding duration. 2) To assess the association with sex, age, need of dialysis, antibiotics, and STEC serotypes.

Population And Methods: Prospective, observational, longitudinal, and analytical study in the 2013-2019 period. Stool cultures were done upon admission and every 5-7 days until 2 negative results were obtained. Shedding duration was defined as the period from diarrhea onset to the first negative result. STEC was confirmed with polymerase chain reaction detection of stx1, stx2, and rfbO157 genes. The mean (95 % CI) and percentile values of the STEC shedding duration were estimated, and the studied outcome measures were compared using the t test.

Results: A total of 43 patients were included. The mean duration of shedding was 10.2 days (95 % CI: 8.92-11.59), range: 3-22 days. After 15 days, 90 % of patients had a negative stool culture. There were no differences in terms of sex (p = 0.419), age (p = 0.937), need of dialysis (p = 0.917), antibiotics (p = 0.147) or serotype (p = 0.231).

Conclusion: Fifteen days after the onset of diarrhea, 90 % of patients had a negative stool culture, and all patients had one after 22 days. No association was observed between the duration of shedding and studied outcome measures.