Impact of Helminth Infection on the Clinical and Microbiological Presentation of Chagas Diseases in Chronically Infected Patients

PLoS Negl Trop Dis. 2016 Apr 26;10(4):e0004663. doi: 10.1371/journal.pntd.0004663. eCollection 2016 Apr.

Abstract

Background: Helminth infections are highly prevalent in tropical and subtropical countries, coexisting in Chagas disease endemic areas. Helminth infections in humans may modulate the host immune system, changing the Th1/Th2 polarization. This immunological disturbance could modify the immune response to other infections. The aim of this study is to evaluate the relationship between clinical, microbiological and epidemiological characteristics of Chagas disease patients, with the presence of helminth infection.

Methods: A prospective observational study was conducted at Vall d'Hebron University Hospital (Barcelona, Spain). Inclusion criteria were: age over 18 years, diagnosis of Chagas disease, and not having received specific treatment for Chagas disease previously to the inclusion. The study protocol included Chagas disease assessment (cardiac and digestive evaluation, detection of T. cruzi DNA measured by PCR in peripheral blood), and helminth infection diagnosis (detection of IgG anti-Strongyloides stercoralis by ELISA, microscopic examination of stool samples from three different days, and specific faecal culture for S. stercoralis larvae).

Results: Overall, 65 patients were included, median age was 38 years, 75.4% were women and most of them came from Bolivia. Cardiac and digestive involvement was present in 18.5% and 27.7% of patients respectively. T. cruzi PCR was positive in 28 (43.1%) patients. Helminth infection was diagnosed in 12 (18.5%) patients. No differences were observed in clinical and epidemiological characteristics between patients with and without helminth infection. Nevertheless, the proportion of patients with positive T. cruzi PCR was higher among patients with helminth infection compared with patients without helminth infection (75% vs 35.8%, p = 0.021).

Conclusions: We observed a high prevalence of S. stercoralis infection among chronic Chagas disease patients attended in our tropical medicine unit. Strongyloidiasis was associated with significantly higher proportion of positive T. cruzi RT-PCR determined in peripheral blood.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Animals
  • Antibodies, Helminth / blood
  • Chagas Disease / complications*
  • Chagas Disease / epidemiology*
  • Chagas Disease / parasitology
  • Chronic Disease
  • DNA, Protozoan / genetics
  • DNA, Protozoan / isolation & purification
  • Enzyme-Linked Immunosorbent Assay
  • Feces / parasitology
  • Female
  • Hospitals, University
  • Humans
  • Male
  • Middle Aged
  • Polymerase Chain Reaction
  • Prospective Studies
  • Spain / epidemiology
  • Strongyloides stercoralis / immunology
  • Strongyloides stercoralis / isolation & purification
  • Strongyloidiasis / complications*
  • Strongyloidiasis / parasitology
  • Trypanosoma cruzi / genetics
  • Trypanosoma cruzi / isolation & purification
  • Young Adult

Substances

  • Antibodies, Helminth
  • DNA, Protozoan

Grants and funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. This study was supported by the 6th National Plan (PN) of Research + Development + Innovation (I+D+I) 2008-2011, ISCIII-General Division Networks and Cooperative Research Centres + FEDER funds + Collaborative Research Network on Tropical Diseases (RICET): RD12/0018/0020 and RD12/0018/0011. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.