Vitamin D levels in patients with a clinical diagnosis of tuberculosis

Introduction Vitamin D influences the immune response in TB and low Vit D levels are associated with increased TB risk. Aims and objectives This prospective study looked at Vit D levels in patients with a confirmed diagnosis of TB and aimed to correlate the levels with various parameters including the site of disease. Methods All confirmed patients with TB (Jan-Dec 2012) had Vit D level (IDS 1,25-di(OH)vitamin D 3 ELISA) assayed. Levels ≤ 25 nmol/L considered deficient and 25-50 nmol/L considered insufficient. Data were expressed as median ± SEM. Correlations were drawn with sex, site of disease, ethinicity and AAFB isolation. Results 40 patients had confirmed TB over the period analysed, 26 had Vit D levels assayed. The mean age was 38.2 ± 16.7 with 14 males, 12 females. The median Vit D level was 33 ± 4.8 nmol/L. 17/26 (65.4%) had AAFB isolated by smear and/or culture. 5/26 (19%) were born in the UK. 20/26 (76.9%) had pulmonary disease and the rest extra-pulmonary. There was no difference in levels among different ethnic groups. The Vit D levels are shown in the table below. Conclusions The Vit D levels in most patients with confirmed TB were insufficient. While Vit D levels in the males were significantly lower, there was no significant difference with site of disease, ethnicity, being born in the UK or if the patients isolated AAFB. Further studies with larger sample size with normal controls and patients with latent TB would provide useful data to evaluate the significance.