Comparative Assessment of Helicobacter pylori stool Ag and serum Antibodies Tests with Urea Breath Test among Symptomatic Patients at a Tertiary Hospital in Kabul, Afghanistan

Background: Helicobacter pylori infection is a major cause of gastrointestinal disorders. Accurate diagnosis is essential for proper management, particularly in resource-limited settings. We compared the diagnostic performance of stool antigen (Ag) and serum antibody (Ab) tests with the Urea Breath Test (UBT), the gold standard for detecting H. pylori infection, among symptomatic patients at a tertiary hospital in Kabul, Afghanistan, in 2023. Methods: This case series study included dyspeptic patients attending the outpatient department of Cure Hospital, Kabul, Afghanistan, who had not used proton pump inhibitors in the previous two weeks or antibiotics in the past four weeks. All patients underwent stool antigen testing, serum antibody testing, and UBT. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) were calculated to assess diagnostic accuracy. Results: Of the 66 patients enrolled (mean age = 36.4 ± 13.2 years; 68.2% were female), abdominal pain (93%) was the most common symptom. The stool antigen test showed high sensitivity (96%) and specificity (97.5%), while the serum antibody test exhibited lower sensitivity (73%) and specificity (67.5%). Sex-stratified analysis showed consistently high accuracy across for the stool antigen test across both sexes, while the performance of the antibody test varied by sex. Conclusion: The stool antigen test shows high sensitivity and specificity and performs better than the serum antibody test for diagnosing H. pylori infection among symptomatic patients. It can be considered a reliable alternative to UBT in resource-limited settings.