An Outbreak of Shiga Toxin-Positive Enteroaggregative Escherichia coli O104:H4 Related Hemolytic Uremic Syndrome in Turkey: A Multicenter Study.

Introduction: Serious outbreaks of Shiga toxin-producing Escherichia coli-associated hemolytic uremic syndrome (STEC-HUS) have been reported globally. In 2011, Germany experienced a significant outbreak of HUS caused by enteroaggregative E. coli (EAEC) O104:H4 strain. Since then, no other outbreaks of this strain have been reported. This study aims to evaluate pediatric patients affected by the second documented worldwide outbreak of STEC-HUS (EAEC O104:H4 serotype) contaminating local drinking water.

Methods: Medical records of patients hospitalized in five pediatric intensive care units (PICUs) diagnosed with STEC-HUS between July and September 2022 were evaluated retrospectively.

Results: Eighteen patients (14 girls and 4 boys) were enrolled in the study. The median age was 7.4 (Interquartile range [IQR] 1.3-17) years. Abdominal pain was the most common symptom (100%). The mean duration between symptom onset and development of STEC-HUS was 3 days (IQ 1-9). EAEC O104:H4 serotype was detected in the stool samples of 8 patients. Neurological involvement was observed in 3 patients, cardiac involvement in 2 patients, and both in 1 patient. Two patients required respiratory support and dialysis was performed in 16 (88.8%) patients. Plasmapheresis was administered to 2 patients, and eculizumab was given to four. No mortality was reported during follow-up; the mean durations of PICU and hospital stays were 11.3 and 31.6 days, respectively.

Conclusion: Outbreaks of HUS can have serious impacts on both mortality and morbidity. However, timely diagnosis and implementation of appropriate supportive care, including dialysis, respiratory support, and medical treatment for eligible patients, can lead to favorable outcomes.