Relationship between Escherichia coli O157:H7 and diabetes mellitus

Ingestion of Escherichia coli O157:H7 can cause a spectrum of acute illness, ranging from overt hemolytic-uremic syndrome (HUS), to gastroenteritis with bloody diarrhea, to no symptoms. This organism has been responsible for dozens of outbreaks of gastroenteritis and HUS in industrialized nations, and thus is a major public health concern. Although the acute effects of E. coli O157:H7 ingestion are well understood, the long-term complications are less well known. Here, we review the biological and empirical evidence supporting a link between E. coli O157:H7 and long-term diabetes mellitus. Survivors with diarrhea-associated HUS have a significantly increased incidence of diabetes due to complete insulin deficiency, which may recur several years after the initial infection. However, less severe forms of infection, such as E. coli O157:H7 gastroenteritis without overt HUS, do not appear to result in an increased risk of type 2 diabetes.