Vitamin A Supplementation for Modulation of Mycobacterium Tuberculosis Immune Responses in Latent Tuberculosis
Status:
Withdrawn
Trial end date:
2012-12-01
Target enrollment:
Participant gender:
Summary
In populations with high prevalence of latent tuberculosis infection (LTBI), malnutrition
(PEM) may influence incident rates of TB. PEM and specific micronutrient deficiencies
compromise cell mediated immunity (CMI) and increase susceptibility to, or severity of
infections. Vitamin A supplementation significantly reduces all-cause child mortality. The
mechanism of the benefits of supplementation on clinical outcomes is largely unknown, but is
likely to be related to an influence on the immune system. Vitamin A supplementation promotes
lymphogenesis and induces a higher proportion of CD4 naïve T-cells in children. Most cases of
LTBI that progress to active disease are vitamin A deficient. Vitamin A deficiency is common
in most TB endemic countries. At the MRC, 32% of TBCC contacts were vitamin A deficient.
Hypothesis:
The investigators plan to test the hypotheses: that supplementation with vitamin A will
affect the magnitude and quality of immune responses to mycobacterial antigens and
progression to clinical disease.
Phase:
N/A
Details
Lead Sponsor:
Medical Research Council Unit, The Gambia
Collaborators:
Department of State for Health and Social Welfare, The Gambia European and Developing Countries Clinical Trials Partnership (EDCTP)