title: Helicobacter pylori infection in infants and toddlers in South America: concordance between [13C]urea breath test and monoclonal H. pylori stool antigen test.
abstract: Accurate noninvasive tests for diagnosing Helicobacter pylori infection in very young children are strongly required. We investigated the agreement between the [(13)C]urea breath test ([(13)C]UBT) and a monoclonal ELISA (HpSA) for detection of H. pylori antigen in stool. From October 2007 to July 2011, we enrolled 414 infants (123 from Brazil and 291 from Peru) of ages 6 to 30 months. Breath and stool samples were obtained at intervals of at least 3 months from Brazilian (n = 415) and Peruvian (n = 908) infants. [(13)C]UBT and stool test results concurred with each other in 1,255 (94.86%) cases (kappa coefficient = 0.90; 95% confidence interval [CI] = 0.87 to 0.92). In the H. pylori-positive group, delta-over-baseline (DOB) and optical density (OD) values were positively correlated (r = 0.62; P < 0.001). The positivity of the tests was higher (P < 0.001; odds ratio [OR] = 6.01; 95% CI = 4.50 to 8.04) in Peru (546/878; 62.2%) than in Brazil (81/377; 21.5%) and increased with increasing age in Brazil (P = 0.02), whereas in Peru it decreased with increasing age (P < 0.001). The disagreement between the test results was associated with birth in Brazil and female gender but not with age and diarrhea. Our results suggest that both [(13)C]UBT and the stool monoclonal test are reliable for diagnosing H. pylori infection in very young children, which will facilitate robust epidemiological studies in infants and toddlers.
authors.affiliation: Laboratory of Research in Bacteriology, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Dulciene Maria Magalhães
authors.initials: DM
authors.lastname: Queiroz
authors.forename: Mayuko
authors.initials: M
authors.lastname: Saito
authors.forename: Gifone Aguiar
authors.initials: GA
authors.lastname: Rocha
authors.forename: Andreia Maria Camargos
authors.initials: AM
authors.lastname: Rocha
authors.forename: Fabrício Freire
authors.initials: FF
authors.lastname: Melo
authors.forename: William
authors.initials: W
authors.lastname: Checkley
authors.forename: Lúcia Libanez Bessa C
authors.initials: LL
authors.lastname: Braga
authors.forename: Igor Simões
authors.initials: IS
authors.lastname: Silva
authors.forename: Robert H
authors.initials: RH
authors.lastname: Gilman
authors.forename: Jean E
authors.initials: JE
authors.lastname: Crabtree
mesh_terms: D000942:Antigens, Bacterial / Q000032:analysis; D001938:Brazil / Q000453:epidemiology; D001944:Breath Tests / Q000379:methods*; D002675:Child, Preschool; D019411:Clinical Laboratory Techniques / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005243:Feces / Q000382:microbiology; D005260:Female; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D010568:Peru / Q000453:epidemiology; D015995:Prevalence; D014510:Urease / Q000032:analysis
chemical_list: D000942:Antigens, Bacterial; D014510:Urease