Cryptosporidiosis in HIV/AIDS patients in Kenya: clinical features, epidemiology, molecular characterization and antibody responses

Abstract

We investigated the epidemiological and clinical features of cryptosporidiosis, the molecular characteristics of infecting species and serum antibody responses to three Cryptosporidium-specific antigens in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients in Kenya. Cryptosporidium was the most prevalent enteric pathogen and was identified in 56 of 164 (34%) of HIV/AIDS patients, including 25 of 70 (36%) with diarrhea and 31 of 94 (33%) without diarrhea. Diarrhea in patients exclusively infected with Cryptosporidium was significantly associated with the number of children per household, contact with animals, and water treatment. Cryptosporidium hominis was the most prevalent species and the most prevalent subtype family was Ib. Patients without diarrhea had significantly higher serum IgG levels to Chgp15, Chgp40 and Cp23, and higher fecal IgA levels to Chgp15 and Chgp40 than those with diarrhea suggesting that antibody responses to these antigens may be associated with protection from diarrhea and supporting further investigation of these antigens as vaccine candidates.

Figure 1.

Schematic showing numbers of human immunodeficiency virus (HIV)-infected patients enrolled in the study with and without diarrhea and with and without Cryptosporidium infection. OEP = other enteric pathogens.

Figure 2.

Serum immunoglobulin G (IgG) antibodies to Chgp15, Chgp40, and Cp23: Serum IgG antibodies to specific antigens in Cryptosporidium spp.-infected human immunodeficiency virus (HIV)-positive patients with or without diarrhea were measured by enzyme-linked immunosorbent assay (ELISA) as described in the Materials and Methods.

Figure 3.

Fecal immunoglobulin A (IgA) antibodies to Chgp15 and Chgp40: Fecal IgA antibodies to specific antigens in Cryptosporidium spp.-infected human immunodeficiency virus (HIV)-positive patients with or without diarrhea were measured by enzyme-linked immunosorbent assay (ELISA) as described in the Materials and Methods.