Commentary: biopsy to diagnose GERD - better, but not yet a stand-alone test

Abstract

Empiric medical therapy with a proton pump inhibitor (PPI) is recommended in patients with typical heartburn. These patients are presumed to have gastro-oesophageal reflux disease (GERD). However, the sensitivity and specificity of the history and PPI response to diagnose GERD are mediocre.1, 2 As such, many with continued heartburn require a diagnostic work up that typically includes endoscopy and pH or impedance-pH studies, to differentiate refractory GERD3 from functional heartburn (FH). Routine biopsies of the distal oesophagus to diagnose GERD are not recommended by the recent ACG guidelines.4 Kandulski et al. report a well-designed, prospective study examining the potential for biopsy to distinguish non-erosive reflux disease (NERD) from FH in these refractory patients.5 Endoscopy and impedance-pH study were used as the gold standard tests for NERD and FH. Refractory heartburn (RH), NERD, FH and control groups were clearly defined. Confirmatory tests were carried out off PPI. The pathologist was blinded to other results. Statistical analyses were robust and included correction for multiple comparisons. A semi-quantitative score of 0–3 (absent to severe) for basal cell hyperplasia, papillary elongation and dilated intercellular spaces was given by the pathologist. These scores, individually and collectively, were significantly different between NERD and FH patients (Pm <0.05). A score of ≥5 had 85% sensitivity and 64% specificity to distinguish NERD from FH. The results of this study are encouraging, offering new insights into the potential for oesophageal biopsy to help with diagnosis in these difficult patients. However, the sensitivity and specificity needs substantial improvement and the scoring system requires validation before the results would allow us to recommend routine biopsy. Most importantly, an expert pathologist is needed, particularly to make an accurate assessment of dilated intracellular spaces. At this time, patients with RH still require pH or impedance-pH study after a normal endoscopy to confirm the diagnosis of NERD or FH. Declaration of personal and funding interests: None.