RESUMO
An outbreak of enterohemorrhagic Escherichia coli (EHEC) occurred in Toyama and other prefectures in Japan during 2011. Some patients, including adults, showed complications such as encephalopathy, disseminated intravascular coagulation, and hemolytic-uremic syndrome, and the disease course was extremely aggressive. This report describes the clinical features of four patients infected with Escherichia coli (E. coli) O111 who developed very severe to fatal complications. The initial symptoms in all patients included abdominal pain, diarrhea, and bloody stools, and neurological abnormalities started to appear from 1 to 3 days after admission. Vomiting and pyrexia developed in three patients. Leukocyte counts, lactate dehydrogenase (LDH), and fibrin/fibrinogen degradation products were elevated, and thrombocytopenia was evident. Extremely elevated LDH and severe thrombocytopenia were characteristic at the time encephalopathy became apparent. All patients received oral fosfomycin, intravenous antibiotics, and anticoagulant therapy, three received gamma globulin, plasma exchange, and blood transfusion, and two received steroids and dialysis. Three patients required mechanical ventilation, and two adult patients died. E. coli O111 positive for Shiga toxin 2 was detected in stool culture in two patients, and serological tests for E. coli O111 were positive in the other two patients. In conclusion, EHEC O111 can cause severe illness in children and adults, and the prognosis becomes poorer as the severity of complications increases. Close monitoring including platelet counts and LDH are useful. Once these clinical parameters change, intensive treatment should be provided to prevent the development of severe complications.