Are intestinal helminths risk factors for developing active tuberculosis?

Abstract

Summaryobjectives To determine the prevalence of intestinal helminth infections in active tuberculosis patients and their healthy household contacts and to assess its association with active TB in an area endemic for both types of infections.methods Smear-positive pulmonary TB patients and healthy household contacts were tested for intestinal helminths using direct microscopy and the formol-ether concentration techniques. Three consecutive stool samples were examined before the start of TB chemotherapy. Sputum microscopy was done using the sodium hypochlorite concentration techniques. Participants were also tested for HIV by commercial sandwich enzyme linked immunosorbent assay.results The study population consisted of 230 smear-positive TB patients and 510 healthy household contacts. The prevalence of intestinal helminths was 71% in patients and 36% in controls. HIV seroprevalence was significantly higher in patients than in controls (46.7% vs. 11.6%, P < 0.001). Conditional logistic regression analysis showed a strong association between TB and intestinal helminth infection (OR ¼ 4.2, 95% CI 2.7-5.9, P < 0.001), and between TB and HIV infection (OR ¼ 7.8, 95% CI 4.8-12.6, P < 0.0001). The odds of being a TB patient increased with the number of helminth species per person: in individuals with mono-infection it was 4.3 (95% CI 2.8-6.8); in people infected with two species was 4.7 (95% CI 2.5-8.7), and in patients infected with three or more helminths was 12.2 (3.9-52.6).conclusion Intestinal helminth infection may be one of the risk factors for the development of active pulmonary TB in addition to HIV infection. This finding may have important implications in the control of TB in helminth endemic areas of the world.

Enteroparasitosis prevalence and parasitism influence in clinical outcomes of tuberculosis patients with or without HIV co-infection in a reference hospital in Rio de Janeiro (2000-2006)

“…Recent in vitro studies showed significant correlations between helminthic infections and tuberculosis [10, [18][19][20][21]. In this study, initially, we evaluated the prevalence of enteroparasitosis in tuberculosis patients, HIV-infected or non infected, and we found a prevalence of helminthes similar to that observed by other authors, Strongyloides stercoralis being the most frequent parasite [10,20].…”

Podoconiosis and Soil-Transmitted Helminths (STHs): Double burden of Neglected Tropical Diseases in Wolaita zone, Rural Southern Ethiopia.

“…The overall prevalence of STH infection exceeded that of several other studies in otherwise healthy adult populations in Ethiopia [11,12,23]. However, our study showed similar prevalence of STH infection as other studies investigating STH coinfection in patients with HIV and TB in Hawassa (southern Ethiopia), Jimma (south-western Ethiopia) and north Gonder (northern Ethiopia) [24,25,26]. Higher prevalence of STH in patients than healthy controls in the latter two studies was related to disease progression and immune responses, suggesting that investigation of the effects of the STH infections on disease progression and immune response in podoconiosis would be useful.…”

Intestinal Parasite Co-infection among Pulmonary Tuberculosis Cases without Human Immunodeficiency Virus Infection in a Rural County in China

“…5 Although it was not possible to obviate the impact of participants' sociodemographic characteristics on the difference of infection spectrum between two studies, both findings indicated that infection rates of intestinal parasites in humans were lower in central China than in southern and western China, where infection rates were 40%. 7,8 Previous studies focusing only on the effect of helminth infections on TB suggested that helminth infections may be the risk factor for active PTB in addition to HIV infection, 18 as well as have a negative influence on human immunity against TB. 9,19 However, a review showed that PTB and parasitic diseases were shown to be risk factors for each other.…”