Cryptosporidiosis and inflammatory bowel disease. Experience from the Milwaukee outbreak.

The 1993 Milwaukee Cryptosporidium outbreak posed several questions regarding appropriate management and prognosis of inflammatory bowel disease patients acutely infected with this organism. We prospectively identified and monitored 12 patients with stable ulcerative colitis or Crohn's disease who suffered abrupt clinical decompensation during the outbreak. All recovered to baseline at < or = 60 days. In patients receiving immunosuppressive therapy, mean duration of symptoms was no longer than in patients without it. Antibiotics did not clearly reduce duration of illness. Two additional patients without a history of intestinal disease presented with ileitis and colitis, respectively, initially suggesting Crohn's disease. Both recovered completely without specific therapy. We conclude that cryptosporidiosis may present as an acute relapse of inflammatory bowel disease and responds to standard therapy; antibiotics confer no obvious benefit. Immunosuppressive therapy does not predispose to chronic or severe illness in these patients. Cryptosporidiosis may present with acute findings initially mimicking Crohn's disease.