Epidemiology of Human Intestinal Coccidia in Immunocompromised Patients Across Three Tertiary Hospitals in Lagos State

Human intestinal coccidia including Cryptosporidium, Cyclospora cayetanensis, and Cystoisospora belli cause severe and life-threatening diarrhoea in immunocompromised patients, yet their comparative epidemiology in Nigerian tertiary care settings remains poorly described. This analytical cross-sectional study investigated the prevalence, species distribution, and clinical correlates of intestinal coccidia infections among immunocompromised patients at three tertiary hospitals in Lagos State, Southwest Nigeria. Stool samples from 360 immunocompromised patients comprising HIV-positive individuals, cancer patients on chemotherapy, and organ transplant recipients were examined using modified Ziehl-Neelsen staining, auramine-rhodamine fluorescence staining, and coproantigen ELISA. CD4 counts, immunosuppressive drug regimen details, and diarrhoeal severity scores were documented. Overall coccidian prevalence was 27.5 percent. Cryptosporidium was the most prevalent at 18.3 percent, followed by Cystoisospora belli at 6.4 percent and Cyclospora at 2.8 percent. Patients with CD4 counts below 100 cells per microlitre had seven times higher odds of coccidian infection. Co-infection with two coccidian species was identified in 4.2 percent of patients. Fluorescence microscopy demonstrated superior sensitivity over modified acid-fast staining. The study recommends adoption of fluorescence-based methods in tertiary hospital parasitology laboratories and routine coccidian screening for all immunocompromised patients admitted with diarrhoea in Lagos State. Keywords: intestinal coccidia, Cryptosporidium, immunocompromised patients, Lagos State, coccidiosis.