Background:  The difficulty in diagnosing lung tuberculosis (TB) in children is still challenging and contribute to high morbidity. Recent study in adult have found an association between low level of vitamin D and less immunity of the host against tuberculosis. The aim of this study is to evaluate vitamin D levels and its role as predictor in diagnosing lung TB in children ?5 years old.
Methods: This comparative study with a cross-sectional design was conducted in our outpatient clinic from February 2018 – February 2019. We selected children ?5 years old, diagnosed with lung TB; control group were random siblings or neighbors who didn’t have tuberculosis. Children with liver or kidney abnormalities, immunocompromized and already receive vitamin D supplementation are excluded. Differences in vitamin D levels in both groups were statistically analyzed with t-test. Receiver operating characteristic (ROC) curve analysis was used to identify optimal cutoff values of Vitamin D level.
Results: The subjects were 35 children with lung TB and 35 healthy children. Mean Vitamin D level in TB group is 42.72 nmol/L and 97.74 nmol/L in healthy children. Vitamin D levels in TB group is significantly lower than healthy children (p<0,001). The best cutoff point level for vitamin D is 80nmol/L, with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 100%, 97.1%, 97.2%, and 100%, respectively.
Conclusion: Serum levels of vitamin D in lung TB is significantly lower than healthy children. Vitamin D level can be considered as predictor for diagnosis of lung TB in children.