OBJECTIVE: Pulmonary tuberculosis (TB) in children still be a high burden in developing countries, including Indonesia. There are wide varieties in clinical presentation and it is challenging to make diagnosis. Aim of this study was to assess sputum GeneXpert MTB/RIF (Xpert) and tuberculin skin test (TST) as a diagnostic tools of childhood pulmonary TB.
METHOD: A descriptive analytic cross-sectional study was done in TB outpatient clinic of Prof. Dr. R.D. Kandou General Hospital from January 2014 to January 2019. Samples were taken concecutively. Inclusion criteria were children aged 3 months-18 years old and diagnosed as pulmonary TB based on clinical symptoms from World Health Organization (WHO) Guidance for National Tuberculosis Programmes 2014. Exclusion criteria was parents who reject to participate in the study. All samples were examined for TST and sputum Xpert. Results of samples characteristics, TST, and Xpert were described with SPSS ver 22.0. Analysis were also done to search correlation between TST and Xpert using pearson chi-square test (significant if p?0.05).
RESULT: Eighty-nine children met the inclusion criteria. Median age was 11 (1-18) years old with median weight of 28 (7-60) kg. Twenty eight (31.5%) children were TST positive. Twenty four (27%) children were Xpert “detected” with only one (0.04%) rifampicin resistent. From 28 children with TST positive, 13 (46.4%) were Xpert “detected”. From 61 children with TST negative, 11 (18%) were Xpert “detected”. When combine, both TST and Xpert were positive in 39 (43%) children. Person chi-square test results were showing positive correlation between TST and Xpert, with positive Xpert results were found more frequently in children with positive TST (OR 3.93 1.466-10.589 CI 95%, p=0.05). 
CONCLUSION: Sputum Xpert and TST, each had low detection rate of pulmonary TB in children. Both diagnostic tools must be used concurrently to support the diagnosis of pulmonary TB in children.