title: Evaluation of the Xpert MTB/RIF assay in gastric lavage aspirates for diagnosis of smear-negative childhood pulmonary tuberculosis.
abstract: BACKGROUND
  The diagnosis of pulmonary tuberculosis (TB) in children presents problems worldwide. The Xpert MTB/RIF assay serves as a useful alternative for the rapid diagnosis of childhood TB, with various clinical specimens.
  
  
  METHODS
  In this study, we evaluated the Xpert for diagnosis of smear-negative childhood pulmonary TB using gastric lavage aspirates (GLA). A total of 211 eligible children with suspected TB were consecutively recruited and had GLA obtained for analysis between October 2012 and October 2013 in Beijing Children's Hospital.
  
  
  RESULTS
  The percentages of TB children in <1 year [Odds ratio (95% confidence interval): 4.66 (1.81-11.97)], >5 years group [2.59 (1.30-5.16)] and of living in a rural region [3.78 (2.02-7.08)] were significantly higher than in control groups. The sensitivity in detecting children with a clinical diagnosis of TB for MGIT and Xpert was 12.1% (95% confidence interval: 9.3-14.9%) and 48.6% (95% confidence interval: 44.4-52.8%), respectively. The statistical analysis revealed that GeneXpert showed significantly better sensitivity than MGIT technology (P < 0.001).
  
  
  CONCLUSIONS
  We conclude that Xpert MTB/RIF assay is an excellent tool for the diagnosis of smear-negative childhood with GLA samples. The high proportion of very low mycobacterial load in the GLA samples from smear-negative TB cases may increase the frequency for obtaining indeterminate RIF resistance results by Xpert. In addition, the age <1 year, >5 years and living in a rural region are all high risk factors for childhood TB cases in China.
authors.affiliation: From the *Beijing Children's Hospital, Capital Medical University; and †National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Pang
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Shunying
authors.initials: S
authors.lastname: Zhao
authors.forename: Jinrong
authors.initials: J
authors.lastname: Liu
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Zhao
authors.forename: Huimin
authors.initials: H
authors.lastname: Li
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002681:China; D005751:Gastric Lavage / Q000379:methods*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D009161:Mycobacterium / Q000235:genetics / Q000302:isolation & purification*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*