Intestinal protozoa in HIV-infected patients in Apulia, South Italy

Protozoa are important enteric pathogens in patients with human immunodeficiency virus (HIV) infection. In this study the prevalence of intestinal protozoa in 154 HIV-infected patients, with or without diarrhoea, in our region (Apulia, South Italy) was evaluated between December 1993 and February 1998. In the majority of patients CD4+ T cell count was below 200/mu l. The overall prevalence of intestinal protozoa was 43/154 (27.92%). Twenty-eight (43.08 %) out of 65 patients with diarrhoea and 15 (16.85 %) out of 89 non-diarrhoeic patients were parasitized. In particular, in the group of 65 patients with diarrhoea the following protozoa were identified: Cryptosporidium parvum in 14 (21.54 %), Blastocystis hominis in 7 (10.77 %), microsporidia in 6 (9.23 %), Giardia lamblia in 4 (6.15 %) and Isospora belli in 1 (1.54%). Three patients were Cryptosporidium parvum-microsporidia co-infected. In patients without intestinal symptoms, prevalence was 3/89 (3.37 %) for Cryptosporidium parvum, 9/89 (10.11 %) for Blastocystis hominis, 1/89 (1.12 %) for microsporidia and 2/89 (2.25 %) for Giardia lamblia. A significant (P < 0.001) correlation was observed between protozoan infection and the presence of diarrhoea. In particular, Cryptosporidium parvum and microsporidia infections were significantly (P < 0.001) and P = 0.046, respectively) associated with diarrhoeal illness. Moreover, the majority of cases of cryptosporidiosis were first diagnosed in the periods of heaviest rainfall. Therefore, drinking water contamination may be a possible source of human infection in our area.