Vitamin D status in under-five children with a history of close tuberculosis contact in Padang, West Sumatra

Background and Objective: Serum vitamin D influences cellular immunity against Mycobacterium tuberculosis, particularly in under-five children. Vitamin D insufficiency and deficiency as well as tuberculosis (TB) are highly prevalent in Indonesia. This study described the association of serum vitamin D in the incidence of latent TB in under-five children with a history of close TB contact. Methods and Study Design: This cross-sectional study examined 178 under-five children with a history of close TB contact, with 98 index cases from primary health care facilities in Padang. Latent TB was defined based on a positive tuberculin skin test. Serum vitamin D was determined using ELISA method. General characteristics for age, sex, socioeconomic status, contact score, BCG scars, and nutritional status were also collected. Results: Of 168 eligible subjects, 40.5% had latent TB, however no differences between 'latent TB' and 'without latent TB' were observed in participant characteristics. Vitamin D deficiency, insufficiency, and sufficiency were observed in 23.3%, 43.5%, and 33.3% of children, respectively. In general, the 'latent TB' group had lower serum vitamin D than those in the 'without latent TB' group, stratified by age, contact score and nutritional status; however, significant differences were observed in children age < 1 years (18.0±2.6 vs 31.2±10.5, respectively, p=0.013). Nevertheless, no associations between the two groups were observed using multivariate analysis. Conclusion: Vitamin D status was not associated with the incidence of latent TB among under-five children with a history of close TB contact, although this may not obtain in children aged < 1 year old.