Cryptosporidium infection in patients with major histocompatibility complex class II deficiency syndrome in Tunisia: description of five cases

In Tunisia, Cryptosporidium is frequently identified in diarrheic stools of children and immunocompromised patients. The infection is usually self-limited in immunocompetent populations, but can be severe and life-threatening in immunocompromised individuals. Cryptosporidiosis is well-documented in patients with the human immunodeficiency virus; however, few data are available concerning children with primary immunodeficiencies (PIDs). A retrospective study was conducted on 5 cryptosporidiosis cases diagnosed in 11 children with PIDs. Cryptosporidium was systematically investigated when patients presented chronic diarrhea. Stool samples were examined for the parasite oocysts by modified Ziehl-Neelsen staining, and DNA was systematically extracted for a nested polymerase chain reaction (PCR). The species were identified by the analysis of restriction patterns. Epidemiological and clinicobiological data were presented for each patient. All cryptosporidiosis cases presented a CMH class II deficiency syndrome. Chronic diarrhea was associated with failure to thrive in all cases. PCR provided the diagnosis in all patients, while Ziehl-Neelsen staining revealed Cryptosporidium oocysts in only 3 cases. Species identification yielded Cryptosporidium hominis in 2 cases, Cryptosporidium meleagridis in 1 case, and Cryptosporidium parvum in 1 case; a C. hominis/C. meleagridis co-infection was observed in the last case. C. hominis was isolated in children from rural areas, suggesting that the infection could have been contracted in the hospital and thus a probability of nosocomial transmission. One of the C. hominis carriers developed sclerosing cholangitis with a high parasite load. Cryptosporidiosis with serious clinical symptoms is observed in PID patients, particularly those with CMH class II deficiency syndrome. Early, regular, and repeated screening, improved by PCR, is recommended in this group of patients. The predominance of C. hominis, the anthropophilic species, in children from rural areas should emphasize hygiene measures in care centers where PID cases are treated.