Altered Cervical Mucosal Gene Expression and Lower Interleukin 15 Levels in Women With Schistosoma haematobium Infection but Not in Women With Schistosoma mansoni Infection.

BACKGROUND: Schistosomiasis increases the risk of human immunodeficiency virus (HIV) acquisition in women by mechanisms that are incompletely defined. Our objective was to determine how the cervical environment is impacted by Schistosoma haematobium or Schistosoma mansoni infection by quantifying gene expression in the cervical mucosa and cytokine levels in cervicovaginal lavage fluid. METHODS: We recruited women with and those without S. haematobium infection and women with and those without S. mansoni infection from separate villages in rural Tanzania with high prevalences of S. haematobium and S. mansoni, respectively. Infection status was determined by urine and stool microscopy and testing for serum circulating anodic antigen. RNA was extracted from cervical cytobrush samples for transcriptome analysis. Cytokine levels were measured by magnetic bead immunoassay. RESULTS: In the village where S. haematobium was prevalent, 110 genes were differentially expressed in the cervical mucosa of 18 women with versus 39 without S. haematobium infection. Among the 27 cytokines analyzed in cervicovaginal lavage fluid from women in this village, the level of interleukin 15 was lower in the S. haematobium-infected group (62.8 vs 102.9 pg/mL; adjusted P = .0013). Differences were not observed in the S. mansoni-prevalent villages between 11 women with and 29 without S. mansoni infection. CONCLUSIONS: We demonstrate altered cervical mucosal gene expression and lower interleukin 15 levels in women with S. haematobium infection as compared to those with S. mansoni infection, which may influence HIV acquisition and cancer risks. Studies to determine the effects of antischistosome treatment on these mucosal alterations are needed.

Schistosomiasis and hydration status: Schistosoma haematobium, but not Schistosoma mansoni increases urine specific gravity among rural Tanzanian women.

OBJECTIVES: Schistosome infections can damage organs important for water homeostasis, especially the kidneys. Urogenital schistosomiasis (caused by Schistosoma haematobium) increases protein and blood in urine and intestinal schistosomiasis (caused by S. mansoni) affects total body water. However, no data exist on how different schistosome species affect urine specific gravity (USG), a hydration biomarker. Therefore, we assessed the relationship between S. haematobium- and S. mansoni-infected and uninfected women and USG in rural Tanzania. MATERIALS AND METHODS: Surveys were conducted and stool and urine samples were collected among 211 nonpregnant women aged 18-50. S. haematobium eggs were detected using the urine filtration method. S. mansoni eggs were detected using the Kato Katz method. USG was measured using a refractometer and analyzed as both a continuous and dichotomous variable. Regression (linear/logistic) models were estimated to test the relationship between infection and hydration status. RESULTS: The prevalence of S. haematobium was 5.9% and S. mansoni was 5.4% with no coinfections. In regression models, S. haematobium-infected women had significantly higher USG (Beta = 0.007 g mL-1 ; standard error = 0.002; p = 0.001) and odds (Odds ratio: 7.76, 95% CI: 1.21-49.5) of elevated USG (>1.020 g mL-1 ) than uninfected women, whereas S. mansoni-infected women did not. DISCUSSION: Schistosoma haematobium, but not S. mansoni, infection is associated with higher USG and risk of inadequate hydration. Future work should determine whether findings are attributable to parasite-induced debris in urine or urinary tract pathologies and signs of renal damage. Human and non-human primate studies using USG in schistosome-endemic areas should account for schistosomiasis.