Validation of a rapid stool antigen test for diagnosis of Helicobacter pylori infection Validação de teste rápido de antígeno fecal para diagnóstico de infecção por Helicobacter pylori

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Joyce Matie Kinoshita da Silva, Cibele Aparecida Villares, Maria do Socorro Monteiro, Carlos Colaúto, Anibal Ferreira dos Santos, Rejane Mattar
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 2010
• Subjects: 13C-urea breath test; H. pylori stool antigen test; H. pylori diagnosis; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic; Falso
• Online Access: https://doi.org/10.1590/S0036-46652010000300002; https://doaj.org/article/dea637993b9746f1a9bcc15dc9c0cd13

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. O objetivo desse trabalho foi avaliar o teste rápido de antígeno de H. pylori nas fezes (One step H. pylori antigen test, ACON laboratories, San Diego, USA; Prime diagnostics, São Paulo), usando teste respiratório com uréia marcada com 13C (TRU-13C), como padrão ouro. Noventa e oito pacientes assintomáticos ou com dispepsia participaram do estudo. Sessenta e nove eram mulheres; a média de idade dos pacientes foi de 45.76 ± 14.59 (14 a 79 anos). No grupo H. pylori positivo, o teste rápido detectou antígenos de H. pylori nas fezes em 44 dos 50 pacientes positivos (sensibilidade de 88%; 95% IC: 75.7-95.5%), com seis falso-negativos; e no grupo H. pylori negativo, 42 apresentaram resultados negativos (especificidade de 87,5%; 95% IC: ...