title: Validation of a rapid stool antigen test for diagnosis of Helicobacter pylori infection.
abstract: The aim of this study was to validate the rapid lateral flow Helicobacter pylori stool antigen test (One step H. pylori antigen test, ACON laboratories, San Diego, USA; Prime diagnostics, São Paulo), using 13C-Urea Breath Test as the gold standard for H. pylori infection diagnosis. A total of 98 consecutive patients, asymptomatic or dyspeptic, entered the study. Sixty-nine were women, with a mean age of 45.76 +/- 14.59 years (14 to 79 years). In the H. pylori-positive group, the rapid stool antigen test detected H. pylori antigen in 44 of the 50 positive patients (sensitivity 88%; 95% CI: 75.7-95.5%), and six false-negative; and in the H. pylori-negative group 42 presented negative results (specificity 87.5%; 95% CI: 74.7-95.3%), and six false-positive, showing a substantial agreement (Kappa Index = 0.75; p < 0.0001; 95% CI: 0.6-0.9). Forty four of fifty patients that had positive stool antigen were H. pylori-positive, the PPV of the stool antigen test was 88% (95% CI: 75.7-95.5%), and 42 patients with negative stool antigen test were H. pylori-negative, the NPV of the stool antigen test was 87.5% (95% CI: 74.7-95.3%). We conclude that the lateral flow stool antigen test can be used as an alternative to breath test for H. pylori infection diagnosis especially in developing countries.
authors.affiliation: Department of Gastroenterology, University of São Paulo School of Medicine, São Paulo, SP, Brazil. jmkino@hcnet.usp.br
authors.forename: Joyce Matie Kinoshita da
authors.initials: JM
authors.lastname: Silva
authors.forename: Cibele Aparecida
authors.initials: CA
authors.lastname: Villares
authors.forename: Maria do Socorro
authors.initials: Mdo S
authors.lastname: Monteiro
authors.forename: Carlos
authors.initials: C
authors.lastname: Colaúto
authors.forename: Anibal Ferreira
authors.initials: AF
authors.lastname: dos Santos
authors.forename: Rejane
authors.initials: R
authors.lastname: Mattar
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000032:analysis*; D005243:Feces / Q000737:chemistry* / Q000382:microbiology; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial