Abstract
Author summary Infection with Blastocystis, a neglected enteric pathogen, is frequently reported in tropical and sub-tropical countries. However, the epidemiology, pathogenicity and associated outcomes of Blastocystis in relation to enteric infections and Environmental Enteric Dysfunction (EED) remain inconclusive. In this study, the authors investigated the factors associated with Blastocystis infection and examined its association with enteric infections as well as fecal biomarkers of environmental enteric dysfunction among slum-dwelling malnourished adults in Bangladesh. The study findings exhibited that nearly 80% of the participants were infected with Blastocystis demonstrating a positive association with crowded living conditions. The authors observed a positive association of Blastocystis with atypical strain of Enteropathogenic Escherichia coli and Trichuris trichiura. The study results also corroborate that infection with Blastocystis had significant negative association with alpha-1 antitrypsin and Reg1B concentrations measured in the stool samples of the study participants. The findings of this study would help to reveal the pathogenic potential of Blastocystis and determine its role in contributing to altered gut health as well as EED in malnourished adults living in resource limited environments.
Background Blastocystis spp. (Blastocystis) is a widely distributed gastrointestinal protist frequently reported in countries with tropical and sub-tropical climate. We sought to determine the factors associated with Blastocystis infection and investigate its role on biomarkers of intestinal health among slum-dwelling malnourished adults in Bangladesh. Methodology Total 524 malnourished adults with a body mass index <= 18.5 kg/m(2) were included in this analysis. Presence of Blastocystis in feces was evaluated by TaqMan Array Card assays. Principal findings Blastocystis was tested positive in 78.6% of the participants. Prevalence of infection with atypical strains of enteropathogenic Escherichia coli (aEPEC) (56% vs. 38%, p<0.001), and Trichuris trichiura (28% vs. 15%, p-value = 0.02) was significantly greater in adults with Blastocystis, while Giardia intestinalis was significantly lower (8% vs. 14%, p-value = 0.04) in Blastocystis positive adults. Malnourished adults who were living in households with high crowding index (aOR = 2.18; 95% CI = 1.11, 4.65; p-value = 0.03), and infected with aEPEC (aOR = 2.14; 95% CI = 1.35, 3.44; p-value = 0.001) and Trichuris trichiura (aOR = 1.97; 95% CI = 1.08, 3.77; p = 0.03) were more likely to be infected with Blastocystis. A significant negative relationship was observed between Blastocystis and fecal concentrations of alpha-1 antitrypsin (beta = -0.1; 95% CI = -1.7, -0.1; p-value<0.001) and Reg1B (beta = -3.6; 95% CI = -6.9, -3.0; p-value = 0.03). Conclusions The study findings suggest that the presence of Blastocystis in human intestine influences gut health and may have potential pathogenic role in presence of other pathogens.