Gastro-esophageal reflux disease (GERD): an appraisal of different tests for diagnosis

Fifty symptomatic patients with GERD, 20 each of non ulcer dyspepsia (NUD) & duodenal ulcer (DU) and 10 healthy controls were subjected to various tests employed for diagnosis of GERD. Among these endoscopy and histology had highest sensitivities (92% & 91% respectively) followed by Bernstein's test (overall 88%; early positivity 72%) and oesophagography (70%). The specificities of various tests were: endoscopy (86%), histology (82%) and Bernstein's test (overall 80%; early positive 94%). The false positivity was mainly in DU subjects where majority (greater than 84%) had two or more of these tests offitive. Any two of the three tests (endoscopy, histology & Bernstein's test) in combination had a sensitivity of 80-91% and a specificity of 90-92%. Our observations suggest that these tests, particularly in combination, are useful in establishing the diagnosis of GERD and that subclinical oesophagitis in DU might be responsible for the false positivity of these tests.