POSSIBLE ROLE OF HELICOBACTER-PYLORI SEROLOGY IN REDUCING ENDOSCOPY WORKLOAD

We validated a commercial enzyme-linked immunosorbent assay (ELISA), H elico-G, in diagnosing H. pylori in 129 patients (mean age 50 years, r ange 15-86). We analysed the results of endoscopy against serology to see whether there was a possibility of adopting the strategy of not en doscoping dyspeptic subjects under the age of 45. H. pylori infection was considered present if either histology and/or culture were positiv e. The ELISA had a sensitivity of 88%, specificity of 72%, positive pr edictive value of 85%, negative predictive value of 77% and accuracy o f 82% in detecting H. pylori. In a subgroup of 52 subjects aged 45 or less (mean age 35 years, range 15-45), 17 out of 25 patients with posi tive endoscopic findings were H. pylori seropositive while 16 out of 2 7 patients had normal endoscopic findings. Eighteen out of the 52 pati ents (35%) were H. pylori seronegative and normal endoscopically excep t for five patients (10%) who had mild to moderate oesophagitis and tw o who had non-erosive gastritis (4%). All patients with duodenal ulcer disease (7) were seropositive giving predictive values of positive an d negative serology for a diagnosis of duodenal ulcer disease as 28% a nd 100%, respectively. Therefore adopting a strategy of endoscoping su bjects under the age of 45 only if they were H. pylori seropositive wo uld have saved 35% of endoscopies in this age group but missed oesopha gitis in 10%. Negative serology would tend to exclude duodenal ulcer d isease while positive serology discriminates poorly for it. Serology m ay be a useful adjunct in screening to reduce endoscopy workload provi ded that patients with gastro-oesophageal reflux symptoms are excluded . Introduction