SevereIsospora (Cystoisospora) belliDiarrhea Preceding the Diagnosis of Human T-Cell-Leukemia-Virus-1-Associated T-Cell Lymphoma

Abstract

Isospora (Cystoisospora) belli diarrhea can sometimes be fulminant in immunocompromised patients. It is endemic in tropical and subtropical areas, and sporadic episodes have been reported in nonendemic areas in nursing homes, day-care centers, and psychiatric institutions. We describe isosporiasis in an HIV-negative Sudanese-American female who presented with a debilitating diarrheal illness and profound weight loss. Isospora belli was detected in her stool by modified acid-fast staining. Serologic testing was negative for HIV but positive for HTLV-1 infection. Treatment with TMP-SMZ led to improvement in her diarrhea which recurred after stopping antibiotics. Subsequently, she developed generalized lymphadenopathy which was diagnosed as ATLL on immunohistochemical staining. Chemotherapy was initiated, but her condition continued to worsen due to persistent diarrhea and resulting profound electrolyte abnormalities. The patient opted for comfort measures and died a few weeks later at a nursing facility. This case emphasizes that the detection of I. belli should trigger testing for HIV, HTLV-1, and other causes of immunocompromise. We suggest that treatment with TMP-SMZ should be initiated and continued for a prolonged period of time in immunocompromised patients with I. belli diarrhea.

Molecular Testing for Clinical Diagnosis and Epidemiological Investigations of Intestinal Parasitic Infections

“…While cystoisosporiasis may be common in nonhuman hosts, human infection by Cystoisospora appears to be relatively rare, and symptomatic infections are probably seen mostly in immunocompromised individuals, including patients with HIV/AIDS or lymphoproliferative disorders, in whom infections are often chronic and severe (198)(199)(200)(201). Superinfection of the small bowel during administration of systemic corticosteroids for eosinophilic gastroenteritis has been documented (202).…”

Eosinophilia in Infectious Diseases

“…In the setting of immunosuppression, diarrhea with malabsorption, dehydration, and weight loss is common. Symptoms may persist for months, and may be the presenting manifestation of underlying malignancy, HIV, or primary immunodeficiency [64-67]. In approximately 50% of patients a mild eosinophilia is seen over the course of illness [68, 69].…”

Update of Human Infections Caused by Cryptosporidium spp. and Cystoisospora belli, Honduras

“…It is assumed that Cryptosporidium does not represent a special threat to patients with malignancies, except for leukemia, where the infection can be severe [33]. On the other hand, many case reports of cystoisosporiasis come from patients with different types of malignancies [34][35][36]. Moreover, as this analysis showed, in 50% of patients <20 years old, C. belli infection was superimposed to an underlying illness.…”