Intestinal Parasitic Infections in HIV and non-HIV Infected Patients with Chronic Diarrhea in Thailand

Abstract

Chronic diarrhea is a common problem in AIDS patients, and enteric parasites are re-cognized as important causes. This study determined the prevalence of parasitic infections in HIV infected patients with chronic diarrhea. Ninety-one patients with AIDS who presented with chronic diarrhea and 103 patients who were HIV negative were enrolled in the study. Detection of stool parasites was made by microscopy of simple smear, formalin-ether concentration method, modified acid-fast and modified trichrome staining techniques. Species identification of microsporidia spores was made by transmission electron microscopy (TEM). Cases in which serial fecal examinations were negative were subjected to gastroduodenoscopy and/or colonoscopy. Parasitic infections were found in 51 (56%) AIDS patients with chronic diarrhea and in 18 (17%) non-HIV cases (p < 0.001). Microsporidia and Cryptosporidium parvum were the most common parasites found in HIV infected patients and were also significantly more prevalent than in non-HIV infected cases [29% vs 0% for microsporidia, (p < 0.001), and 25% vs 1% for C. parvum, (p < 0.001)]. Species identification of microsporidia spores in 26 patients using TEM revealed Enterocytozoon bieneusi in 19 cases. This study indicated that microsporidia and C. parvum are important pathogenic causes of chronic diarrhea in AIDS patients in Thailand.