Severe undernutrition in children affects tuberculin skin test performance in Southern India

PLoS One. 2021 Jul 16;16(7):e0250304. doi: 10.1371/journal.pone.0250304. eCollection 2021.

Abstract

Background: Undernutrition impairs immunity to Mycobacterium tuberculosis and is a risk factor for tuberculosis disease (TB). We aim to investigate if severe undernutrition affects the tuberculin skin test (TST) response among household contacts (HHCs) of pulmonary TB cases.

Methods: We analyzed data from HHCs (> five years) of pulmonary TB cases in Southern India. Undernutrition was defined as per World Health Organization based on body mass index (BMI) for adults (undernutrition 16-18.4 and severe undernutrition <16 kg/m2) and BMI relative to the mean for children (undernutrition 2SD-3SD and severe undernutrition < 3SDs below mean). Univariate and multivariate models of TST positivity (> five mm) were calculated using logistic regression with generalized estimating equations.

Results: Among 1189 HHCs, 342 were children (age 5-17 years) and 847 were adults. Prevalence of TST positivity in well-nourished, undernourished and severely undernourished children was 135/251 (53.8%), 32/68 (47.1%), and 7/23 (30.4%) respectively; among adults, prevalence of TST positivity was 304/708 (42.9%), 43/112 (38.4%) and 12/26 (46.2%), respectively. Severe undernutrition in children was associated with decreased odds of TST positivity (adjusted odds ratio 0.3; 95%CI 0.1-0.9).

Conclusion: Severe undernutrition in children was associated with decreased odds of TST positivity. False-negative TSTs may result from undernutrition; caution is warranted when interpreting negative results in undernourished populations.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Humans
  • India
  • Infant
  • Malnutrition*
  • Prevalence
  • Risk Factors
  • Tuberculin Test*

Grants and funding

This work was supported by US Civilian Research & Development Foundation [Award Number USB1-31150-XX-13]; and National Science Foundation [Cooperative Agreement No. OISE-9531011]. This project was funded in whole or in part with Federal funds from the Government of India’s Department of Biotechnology; the Indian Council of Medical Research; the United States National Institutes of Health; National Institute of Allergy and Infectious Diseases; Office of AIDS Research; and distributed in part by US Civilian Research & Development Foundation Global (award to JJE and GR). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.