Cryptosporidium parvum and other instestinal parasites among diarrhoeal patients referred to EHNRI in Ethiopia

The occurrence of intestinal parasites in patients referred to the Parasitology Laboratory of the Ethiopian Health and Nutrition Research Institute (EHNRI), was recorded for four consecutive years, 1998-2001. Based on the stool appearance i.e. watery, loose, muciod and bloody, 442 diarrhoeal samples were particularly selected to allow diagnosis of intestinal parasites with emphasis on coccidian intestinal parasites. Wet saline mounts and formol ether concentration method with logul's iodine were performed for the detection of cysts, ova, trophozoites and larvae of intestinal parasites. Modified Ziehel Nelseen staining of stool smears was used to identify Cryptosporidum parvum and Isospora belli. The overall detection rate was 79.4% (351/442). The spectrum of positivity with any protozoa was 54.3% (240/442) and helminthes 25.1% (111/442). Cryptosporidium parvum was identified in 92/442 (20.8%). Isopora belli was identified among 35/442 (7.9%): Entamoeba histolytica/dispar scored second with positivity rate of 17.0% (75/442) and Giardia lamblia was found in 38/442 (8.6%) stool samples. As compared to protozoan parasites, detection rate with helminthes was very low. Among the helminthes. Strongyloides stercoralis was found in 38/442 (8.6%). This information strengthens the importance of intestinal protozoan parasites with recognition of the opportunistic parasites as major causes of diarrhoea. Their role in HIV/AIDS patients cannot be over-emphasized. Further awareness for the need of establishing different parasitological techniques at health service giving centers would enhance better understanding and management of diarrhoeal illness.