Extraintestinal amebiasis in infancy: report of three patients and epidemiologic investigations of their families.

Three infants (aged 6 weeks, 7 weeks, and 10 months) had severe Entamoeba histolytica infections characterized by colitis, hepatic abscesses, and peritonitis. The two younger children died after fulminant illnesses while the third recovered. Diagnosis was delayed in all three children by a low index of suspicion and negative stool examinations for parasites. Epidemiologic investigations of the infants' families revealed a high prevalence of amebic infections and elevated antibody titers to E histolytica; however, most family members were asymptomatic. The original source of the infections could not be identified but person-to-person spread within the families was implicated.