C septicum Complicating Hemolytic Uremic Syndrome: Survival Without Surgical Intervention

Clostridium septicum is an anaerobic bacterium that causes rapidly progressive myonecrosis, bacteremia, and central nervous system infection. It has been reported as a complication of Escherichia coli hemolytic uremic syndrome (HUS) in 8 children worldwide; 5 children died, and the 3 reported survivors had surgically treated disease. We present 3 cases of C septicum complicating HUS in children, including the first 2 reported cases of survival without surgical intervention. All patients presented with classic cases of HUS with initial clinical improvement followed by deterioration. Patient 1 had rising fever, tachycardia, and severe abdominal pain 24 hours after admission. She developed large multifocal intraparenchymal cerebral hemorrhages and died 12 hours later. Autopsy revealed C septicum intestinal necrosis, myonecrosis, and encephalitis. Patient 2 had new fever, increasing leukocytosis, and severe abdominal pain on hospital day 4. She was diagnosed with C septicum bacteremia and treated with metronidazole, meropenem, and clindamycin. Patient 3 had new fever and increasing leukocytosis on hospital day 3; blood cultures grew C septicum, and she was treated with penicillin. Patients 2 and 3 improved rapidly and did not require surgery. C septicum is a potential co-infection with E coli. It thrives in the anaerobic environment of E coli–damaged intestinal mucosa and translocates to cause systemic infection. Fever, tachycardia, a rising white blood cell count, and abdominal pain out of proportion to examination are key findings for which physicians should be vigilant. Timely evaluation by anaerobic blood culture and early initiation of antibiotics are necessary to prevent fatalities.