Diagnostic Accuracy of Cartridge Based Nucleic Acid Amplification Test (CBNAAT) in Stool Samples in Pediatric Tuberculosis.

OBJECTIVES

To find out the diagnostic accuracy of stool Cartridge-based nucleic acid amplification test (CBNAAT) as an alternate method as compared to CBNAAT in gastric aspirate (GA) samples in pediatric tuberculosis (TB).

METHODS

This cross-sectional study was performed at Department of Pediatrics of a tertiary care hospital. Children aged 0-18 y diagnosed as presumptive tuberculosis were consecutively enrolled. Gastric aspirate and corresponding stool sample was subjected to CBNAAT and its performance was compared in both samples using appropriate statistical tests.

RESULTS

Total 100 patients were enrolled in the study. Diagnostic accuracy of CBNAAT was 81% and 80% in gastric aspirate and stool sample respectively. On comparing gastric aspirate with corresponding stool sample there was 97% agreement, with Cohen's kappa value of 0.94. There was a statistically significant association observed between gastric aspirate CBNAAT and stool CBNAAT p <0.001 using chi square test. Sensitivity of gastric aspirate CBNAAT and stool CBNAAT was 75% and 73% respectively and specificity was 100% for both the samples compared against Composite Reference Standard (CRS).

CONCLUSIONS

The diagnostic accuracy of stool CBNAAT is comparable to GA CBNAAT in children and can be used as a good alternative to gastric aspirate for diagnosis of pulmonary and disseminated tuberculosis in children.