Outbreak of hemolytic uremic syndrome with unusually severe clinical presentation caused by Shiga toxin-producing Escherichia coli O26:H11 in France

Background: In spring 2019, an outbreak of Shiga toxin-producing Escherichia coli-associated hemolytic ure-mic syndrome (STEC HUS) occurred in France. Epidemiological investigations made by Sante publique France in connection with microbiological investigations at the national reference center for STEC promptly identi-fied a common exposure to consumption of raw cow's milk cheese, and confirmed a cluster affiliation of the E. coli O26:H11 outbreak strain. Here, we report the clinical characteristics of the patients, the treatment used, as well as the outcome at 1 month. Method: Patients with STEC HUS linked to the E. coli O26:H11 outbreak strain were identified from the national surveillance network of pediatric STEC HUS cases coordinated by Sante publique France. Clinical data were analyzed from the patients' hospital records obtained from the treating physicians. Results: Overall, 20 pediatric cases of STEC HUS linked to the outbreak strain were identified. Their median age of the patients was 16 months (range: 5-60). Most of them presented with diarrhea but none had received prior antibiotherapy. A total of 13 patients required dialysis; 10 patients and four patients had central nervous system (CNS) and cardiac involvement, respectively. No deaths occurred. At the 1-month follow-up, only two patients had a decreased glomerular filtration rate, below 80 mL /min/ 1.73m(2) and four had hypertension. One patient had neurological sequelae. Conclusion: The E. coli O26:H11 strain identified as the cause of an STEC HUS outbreak in France in spring 2019 is notable for the initial severe clinical presentation of the patients, with a particularly high frequency of CNS and cardiac involvement similar to the German E. coli O104:H4 outbreak described in 2011. However, despite the initial severity, the 1-month outcome was favorable in most cases. The patients' young age in this outbreak highlights the need to improve information and caregiver awareness regarding consumption of at -risk foods by young children as key preventive measures against STEC infections. (C) 2022 French Society of Pediatrics. Published by Elsevier Masson SAS. All rights reserved.

Automated summary

In spring 2019, an outbreak of STEC HUS associated with E. coli O26:H11 occurred in France. The outbreak was linked to the consumption of raw cow's milk cheese. The patients presented with severe clinical symptoms, particularly involving the central nervous system and the heart. However, most cases had a favorable outcome after one month. The young age of the patients highlights the importance of improving information and caregiver awareness regarding at-risk foods for young children as preventative measures against STEC infections.