title: 13C-urea breath test for the diagnosis of Helicobacter pylori infection in children: a systematic review and meta-analysis.
abstract: BACKGROUND
  The (13) C-urea breath test ((13) C-UBT) is a safe, noninvasive and reliable method for diagnosing H. pylori infection in adults. However, the test has shown variable accuracy in the pediatric population, especially in young children. We aimed to carry out a systematic review and meta-analysis to evaluate the performance of the (13) C-UBT diagnostic test for H. pylori infection in children.
  
  
  METHODS
  We conducted a systematic review of the PubMed, Embase and Liliacs databases including studies from January 1998 to May 2009. Selection criteria included studies with at least 30 children and reporting the comparison of (13) C-UBT against a gold standard for H. pylori diagnosis. Thirty-one articles and 135 studies were included for analysis. Children were stratified in subgroups of <6 and ≥6 years of age, and we considered variables such as type of meal, cutoff value, tracer dose, and delta time for the analysis.
  
  
  CONCLUSIONS
  The (13) C-UBT performance meta-analyses showed 1, good accuracy in all ages combined (sensitivity 95.9%, specificity 95.7%, LR+ 17.4, LR- 0.06, diagnostic odds ratio (DOR) 424.9), 2, high accuracy in children >6 years (sensitivity 96.6%, specificity 97.7%, LR+ 42.6, LR- 0.04, DOR 1042.7), 3, greater variability in accuracy estimates and on average a few percentage points lower, particularly specificity, in children ≤6 years (sensitivity 95%, specificity 93.5%, LR+ 11.7, LR- 0.12, DOR 224.8). Therefore, the meta-analysis shows that the (13) C-UBT test is less accurate for the diagnosis of H. pylori infection in young children, but adjusting cutoff value, pretest meal, and urea dose, this accuracy can be improved.
authors.affiliation: Unidad de Investigación Médica Yucatán, Unidad Médica de Alta Especialidad de Mérida, Instituto Mexicano del Seguro Social, Mérida, Yuc, México. yelda_leal03@yahoo.com.mx
authors.forename: Yelda A
authors.initials: YA
authors.lastname: Leal
authors.forename: Laura L
authors.initials: LL
authors.lastname: Flores
authors.forename: Ezequiel M
authors.initials: EM
authors.lastname: Fuentes-Pananá
authors.forename: Roberto
authors.initials: R
authors.lastname: Cedillo-Rivera
authors.forename: Javier
authors.initials: J
authors.lastname: Torres
mesh_terms: D000293:Adolescent; D001944:Breath Tests / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000378:metabolism*; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D012680:Sensitivity and Specificity; D014508:Urea / Q000378:metabolism*
chemical_list: D014508:Urea