As E. coli O157:H7 can present with signs and symptoms often ascribed to the acute abdomen, it is imperative that doctors are all familiar with this infection and its clinical ramifications.
Originally described in 1983, E. coli O157:H7 is now recognized as a common cause of bloody and nonbloody diarrhea and is responsible for most cases of hemolytic-uremic syndrome in children in North America. In the United States alone, E. coli O157:H7 is believed to cause more than 20,000 infections and approximately 250 deaths each year.
Ingestion of undercooked bovine meat such as hamburger patties has been responsible for many of the large outbreaks of E. coli O157:H7, but other modes of transmission have been reported as well. Infection from pork, chicken, steak, unpasteurized milk, yogurt, vegetables from manured gardens, apple cider, and municipal drinking water have occurred. Sporadic cases have also been attributed to swimming in contaminated lakes, and person-to-person transfers have also been documented in child-care centers, nursing homes, and between family members in the home.
The range of symptoms are broad, often making diagnosis difficult. Patients may be asymptomatic or present with nonbloody diarrhea, bloody diarrhea, the hemolytic-uremic syndrome, thrombocytopenia purpura, seizure, coma, or death. Typically, patients experience crampy abdominal pain and diarrhea, which becomes bloody after 48 hours, and some may have nausea, vomiting, and low-grade fever.
No specific therapy has been proved effective in the treatment of E. coli O157:H7 colitis. Management of HUS includes meticulous attention to fluid balance and electrolyte replacement. Quite often, transfusion of blood products and plasmapheresis is required.
When seeing the patient in consultation, as always, obtaining a thorough history and physical at the time of presentation is of paramount importance. Early suspicion of E. coli O157:H7 infection should lead to more rapid diagnosis, improved hospital courses, and decreased long-term morbidity and mortality.