Objective: To determine the prevalence and clinical manifestations of Cyclospora in Haitians infected with human immunodeficiency virus (HIV) who have diarrhea and to evaluate therapy and prophylaxis.
Design: Cohort study. From 1990 to 1993, stool samples were collected from adults seropositive for HIV who had had diarrhea for at least 3 weeks.
Setting: A clinic in Haiti.
Interventions: Stool samples were examined for enteric protozoa after acid-fast staining. Patients with Cyclospora infection were treated with trimethoprimsulfamethoxazole (160 mg and 800 mg, respectively) given orally four times a day for 10 days. After completion of therapy, patients were evaluated weekly and re-treated if clinical and parasitologic recurrences occurred, followed by trimethoprim-sulfamethoxazole prophylaxis three times a week.
Results: 804 of 2400 patients (33%) seropositive for HIV had a history of chronic or intermittent diarrhea; 502 of these 804 patients (62%) currently had diarrhea, and 450 patients each provided two stool specimens for examination. Enteric protozoa identified included Cryptosporidium (30%), Isospora belli (12%), Cyclospora species (11%), Giardia lamblia (3%), and Entamoeba histolytica (1%). Forty-three patients with diarrhea and Cyclospora infection were studied; their symptoms were indistinguishable from those seen in patients with isosporiasis or cryptosporidiosis. In all patients, diarrhea ceased and results from stool examinations were negative within 2.5 days after beginning oral trimethoprim-sulfamethoxazole therapy. Recurrent symptomatic cyclosporiasis developed in 12 of 28 patients (43%) followed for 1 month or more, but it also responded promptly to trimethoprim-sulfamethoxazole therapy. These 12 patients received trimethoprim-sulfamethoxazole three times a week as secondary prophylaxis, with only a single recurrence after 7 months.
Conclusion: Cyclospora infection is common in Haitian patients with HIV infection, responds to trimethoprim-sulfamethoxazole therapy, and has a high recurrence rate that can be largely prevented with long-term trimethoprim-sulfamethoxazole prophylaxis.