SEROLOGY FOR HELICOBACTER-PYLORI COMPARED WITH SYMPTOM QUESTIONNAIRESIN SCREENING BEFORE DIRECT ACCESS ENDOSCOPY

This prospective study aimed to compare serology for Helicobacter pylo ri with two, symptom questionnaires in screening patients before direc t access endoscopy. Methods were compared in terms of the number of en doscopies saved and pathology missed in 315 patients referred to a gas troenterology unit by 65 local GPs. The serology used was based on an acid glycine extract of H pylori. One in-house questionnaire was based on the Glasgow dyspepsia (GLADYS) system and the other questionnaire was that reported by Holdstock et al. A cut off point of 6.3 U/ml for H pylori serology was selected for screening patients (97% sensitive a nd 75% specific). Serology was combined with a history of NSAID usage in determining who should have endoscopy. For the inhouse questionnair e, a cut off score of more than 8 out of a possible maximum of 18 was chosen, after prior evaluation in 118 patients referred for direct acc ess endoscopy (the sensitivity for detection of peptic ulcer was 88%, specificity 61%). A cut off score of more than 412 was used for the Ho ldstock questionnaire. In patients under 45 years, serology detected m ore peptic ulcers than the in-house questionnaire and the Holdstock qu estionnaire(27/28 v 24/28, NS and v 20/28, p<0.05 respectively). The H oldstock questionnaire saved significantly more endoscopies than the o ther two methods (76/149 v 57/149 for the in-house questionnaire, p=0. 05 and 59/149 for serology, p=0.05). In all age groups combined, serol ogy was significantly better than the in-house and Holdstock questionn aires at detecting peptic ulcers and gastric cancer (61/63, 52/63, p<0 .02, and 50/63, p<0.01 respectively). But serology saved significantly fewer endoscopies (89/315, 135/315, p<0.005, and 119/315, p<0.05 resp ectively). Serology was inferior to the Holdstock questionnaire at det ecting severe oesophagitis. It is concluded that serology is the metho d of choice in screening before direct access upper gastrointestinal e ndoscopy in those under 45 years. It best combines a high sensitivity for peptic ulcer disease with a large reduction in unnecessary negativ e endoscopies.