Risk factors associated with fulminant amebic colitis.

Amebic colitis is associated with serious complications and a high fatality rate if it progresses to its fulminant form. The purpose of this retrospective study was to determine the risk factors associated with fulminant amebic colitis. From February 1978 to February 1993, 60 adults were diagnosed with intestinal amebiasis at Chang Gung Memorial Hospital. Sixteen patients with massive bloody diarrhea, persistent systemic toxicity or signs of peritonitis were classified as having fulminant colitis, five of whom progressed to fulminant colitis after admission to the hospital. Forty-four patients with good responses to amebicides and without complications were classified as having moderate colitis. There was no amebiasis-related mortality among patients with moderate colitis. In contrast, five patients with fulminant colitis died. Early diagnosis and surgical treatment significantly decreased mortality when compared with conservative treatment. Significant factors associated with the development of fulminant intestinal amebiasis in univariate analyses were being male, age over 60 years, having an associated liver abscess, progressive abdominal pain, signs of peritonitis, leukocytosis, hyponatremia, hypokalemia and hypoalbuminemia. Only the factors of being over 60 years of age and hypokalemia were important in multivariate analyses. We conclude that early and extensive surgical treatment is mandatory for patients with typical presentations of fulminant amebic colitis on admission to the hospital, such as progression to peritonitis, persistent systemic toxemia and explosive bloody diarrhea. For other patients, especially the elderly and those with low serum potassium levels, close monitoring and observation for signs of fulminant colitis is important.