Clinically, isosporiasis is indistinguishable from other coccidian
infection such as cryptosporidiosis and cyclosporiasis. It usually
causes self-limiting diarrhea in the immunocompetent host and protracted,
severe diarrhea in the immunocompromised adult and child. Diarrhea
may be acute or chronic. Watery stool, crampy abdominal pain, and
weight loss are characteristic symptoms of isosporiasis. Other patients
may have flulike symptoms, nausea, and vomiting. Fecal blood and
leukocytes are absent. However, Charcot-Leyden crystals and, occasionally,
mucus may be present in the stool.1 Peripheral
eosinophilia is not uncommon.14,15 Severe wasting,
malabsorption, lactose intolerance, and steatorrhea have been reported,
particularly in the immunosuppressed patient. Extraintestinal presentations
such as acalculous cholecystitis and involvement of the lymph nodes,
liver, or spleen are rare but have been reported
in severely immunosuppressed individuals infected with HIV.12,13,16,17