SCREENING DYSPEPTIC PATIENTS FOR HELICOBACTER-PYLORI PRIOR TO ENDOSCOPY - LABORATORY OR NEAR-PATIENT TESTING

Background It is unclear whether near-patient whole-blood diagnostic t ests for Helicobacter pylori are of comparable accuracy to laboratory based ELISA for screening of dyspeptic patients prior to endoscopy. Ai m To compare two ELISA and two whole-blood tests in order to determine whether near-patient H. pylori diagnostic tests are an acceptable alt ernative to laboratory based ELISA tests for screening of dyspeptic pa tients prior to endoscopy, Method One hundred and seven consecutive pa tients with dyspepsia (median age, 32 years; range, 16-45 years) were evaluated with Helico-G ELISA, Hmcap ELISA and Helisal whole-blood tes ts. A further 111 dyspeptic patients (median age, 51 years; range, 16- 96 years) were evaluated with the Immunocard whole-blood test only. Th e 'gold standard' for infection was based on histology and the rapid u rease test (CLO), Results Compared to the Helico-G test, both near-pat ient tests had a higher false negative rate (23-37% vs 5%, P< 0.003), and lower sensitivity and negative predictive value. The Immunocard ha d a higher specificity than did the Helisal (87% vs 63%, P = 0.006); o therwise both near-patient whole-blood tests had similar performance, At a sensitivity of 95%, the Hmcap ELISA was more specific than the He lico-G ELISA (75% vs 67%) and had fewer false positives (25% vs 32%). The near-patient tests would wrongly classify up to 40% H. pylori posi tive dyspeptic patients and exclude them from endoscopy, compared to 5 -6% for ELISA, Conclusions Near-patient whole-blood H. pylori diagnost ic tests are less accurate and thus not an acceptable alternative to l aboratory based ELISA tests. fur J Gastroenterol Hepatol 10:843-846 (C ) 1998 Lippincott Williams & Wilkins.