Detection and Enumeration of the Commonest Stool Parasites Seen in a Tertiary Care Center in South India

The aim of this study was to identify common stool parasites in patients attending a tertiary care centre in South India. We evaluated 2355 stool samples and parasites were detected in 7.9% of samples. 41.1% of our patients were in the 45–58-year age group. Protozoal infections were the commonest seen in 7.8% of samples. Entamoeba histolytica was the commonest protozoa (4.6%) followed by Entamoeba coli (1.2%) and Giardia (0.8%). Entamoeba histolytica and Entamoeba coli were together seen in 0.63%, and they were the commonest organisms seen in samples with multiple-organism infection. Both were equally detected in diarrheal samples. 1. Introduction Approximately, 60% of the world’s population is infected with intestinal parasites [1]. Commonest parasites seen worldwide are Ascaris (20%), Ancylostoma (18%), Trichuris (10%), and Entamoeba histolytica (10%) [2]. The incidence of protozoa and helminthes in stool varies with geographical location. In a study in food handlers in Iran, it was seen that Giardia was the commonest pathogen (4.5%). Other pathogens were Hymenolepis nana (1.29%), Entamoeba histolytica (1.39%), and Ascaris lumbricoides (0.57%). Entamoeba coli was seen in 9.1%, Iodamoeba in 5% and Blastocystis hominis in 11.3% [3]. In an Ethiopian study, prevalence of hookworm was highest (60.2%), followed by Schistosoma mansoni (21.2%), Trichuris (14.7%), Taenia species (13.9%), Entamoeba histolytica (12.7%), Ascaris lumbricoides (6.2%), Giardia (6.2%), and Strongyloides (5.8%) [4]. Eligail et al. reported that the commonest stool parasites reported in Riyadh, Saudi Arabia, were E. coli (4.08%), Iodamoeba (1.79%), Endolimax nana (1.75%), Ascaris (0.67%), Giardia (0.67%), Chilomastix (0.41%), Hookworm (0.36%), E. histolytica (0.14%), Hymenolepis nana (0.10%), Strongyloides (0.07%), Trichomonas (0.06%), Schistosoma mansoni (0.04%), Balantidium (0.04%), Enterobius vermicularis (0.02%), and Taenia species (0.01%) [5]. In western Nepal, Giardia was the commonest (13.2%) followed by Ascaris (2.1%) and Entamoeba histolytica (1.7%) [6]. Study by Sehegal et al. found that prevalence rate of protozoa infection was 81.2% whereas that of helminthes was 18.8% [7]. They found that the commonest pathogen in children and pregnant women was Giardia (21.4% and 6.9%, resp.) followed by E. histolytica (5.3% and 4.6%). In a recent study by Srihari et al., it was found that E. histolytica was the commonest parasite (43.8%) followed by Cryptosporidium parvum (29.8%) and Giardia (10.53%) [8]. In Marothi and Singh’s study, E. histolytica was the commonest (10.5%) followed by