Low incidence of colonic complications after severe Shiga toxin-producing E. coli O104:H4 infection.

BACKGROUND: In summer 2011, Shiga toxin producing Escherichia coli (EHEC) serotype O104:H4 caused the most severe EHEC outbreak in Germany to date. The case of a previously recovered patient with symptomatic postinflammatory colonic stenosis following EHEC- infection prompted us to conduct a prospective study to assess the macro- and microscopic intestinal long-term damage in a cohort of patients who had suffered from severe EHEC colitis. METHODS: Following EHEC infection in 2011, 182 patients were offered to participate in this study between January 2013 and October 2014 as part of the post-inpatient follow-up care at the University Medical Center Hamburg-Eppendorf and to undergo colonoscopy with stepwise biopsies. Prior to colonoscopy, medical history and persistent post-infectious complaints were assessed. RESULTS: Out of 182 patients, 22 (12%) participated in the study, 18 (82%) were female. All patients had been hospitalized due severe EHEC enterocolitis: 20 patients (90%) had subsequently developed hemolytic uremic syndrome (HUS), 16 patients (72%) had additionally required dialysis. On assessment prior to colonoscopy, all patients denied any abdominal complaints before EHEC-infection but 8 (36%) patients reported persistent post-infectious symptoms. According to the ROME IV criteria, 4 (18%) patients met the definition for post-infectious irritable bowel syndrome (PI-IBS). In all patients with persistent symptoms, colonoscopies and histological examination were unremarkable. Only in one symptom-free patient, biopsy revealed a locally limited cryptitis of the caecum, while all patients without complaints had inconspicuous histological and endoscopical findings. CONCLUSION: Following infection colonic stenosis is a serious but rare long-term complication in patients who had suffered from severe enterocolitis. However, a significant proportion of these patients develop PI-IBS.