title: Diagnosis of pediatric pulmonary tuberculosis with special reference to polymerase chain reaction based nucleic acid amplification test.
abstract: OBJECTIVE
  To determine the utility of polymerase chain reaction (PCR) for diagnosing pediatric pulmonary tuberculosis (PPTB).
  
  
  METHODS
  A prospective cross-sectional study was carried out on 100 children less than 14 years of age, with strong clinical suspicion and radiological evidence suggestive of pulmonary tuberculosis (TB). Sputum samples/gastric lavage were collected. Direct smears and culture on Lowenstein Jensen (LJ) media were performed. DNA extraction and amplification was performed using Genei™ Amplification Reagent set for Mycobacterium tuberculosis (MTB) (by Genei, Bangalore, India). This test is based on the principle of single-tube nested PCR which amplifies the repetitive insertion sequence IS6110.
  
  
  RESULTS
  When compared with culture, sensitivity and specificity of PCR was 93.55% and 92.75%, respectively. The PPV was 85.29% and the NPV was 96.97%. When intention to treat (ITT) was used as the standard, sensitivity, specificity, PPV and NPV of PCR was 47.88%, 93.1%, 94.4%, and 42.19%, respectively, and that of culture was 40.85%, 100%, 100% and 40.85%, respectively. Against response to treatment (RTT), PCR demonstrated sensitivity, specificity, PPV and NPV of 50.9%, 93.1%, 93.33% and 50%, respectively, and for culture it was 43.64%, 100%, 100% and 48.33%, respectively.
  
  
  CONCLUSIONS
  The present study reinforces better case detection rate with PCR-based nucleic acid amplification test as compared with microscopy and culture in pediatric pulmonary TB. PCR showed a higher correlation with clinical diagnosis as compared with microscopy and solid culture. Hence, a molecular platform should be the test of choice for detecting PPTB.
authors.affiliation: Department of Microbiology, Seth GSMC & KEM Hospital, Parel, Mumbai 400012, India; AIIMS Bhopal, India. Electronic address: shreshtha.tiwari@gmail.com.
authors.forename: Shreshtha
authors.initials: S
authors.lastname: Tiwari
authors.affiliation: Department of Microbiology, Seth GSMC & KEM Hospital, Parel, Mumbai 400012, India. Electronic address: gitanataraj@gmail.com.
authors.forename: Gita
authors.initials: G
authors.lastname: Nataraj
authors.affiliation: Department of Microbiology, Seth GSMC & KEM Hospital, Parel, Mumbai 400012, India. Electronic address: swapnakanade71@gmail.com.
authors.forename: Swapna
authors.initials: S
authors.lastname: Kanade
authors.affiliation: Department of Microbiology, Seth GSMC & KEM Hospital, Parel, Mumbai 400012, India. Electronic address: prm.kem@gmail.com.
authors.forename: Preeti
authors.initials: P
authors.lastname: Mehta
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005751:Gastric Lavage; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009169:Mycobacterium tuberculosis / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology
keywords: PCR; Pediatric pulmonary tuberculosis