Histology of symptomatic gastroesophageal reflux disease: is it predictive of response to proton pump inhibitors?
BACKGROUND AND AIM
To examine the differences in esophageal histopathology between non-erosive reflux disease (NERD) and reflux esophagitis (RE), and to investigate whether baseline esophageal histopathology can predict the therapeutic response to proton pump inhibitors (PPIs).


METHOD
The subjects comprised 94 patients with NERD (n = 71) or mild RE (n = 23). Tissue was biopsied from 5 cm above the squamo-columnar junction (SCJ), and the degree or presence of nine histopathological markers was assessed. The patients were treated with rabeprazole (RPZ) 10 mg once daily for 4 weeks. If complete heartburn relief was not achieved, RPZ was increased to 10 mg twice daily for another 2 weeks, and then to 20 mg twice daily for another 2 weeks if heartburn remained.


RESULTS
Features of esophageal histopathology 5 cm above the SCJ differed between NERD and RE patients. The esophageal histopathology in patients unresponsive to RPZ was characterized by Protein Gene Product (PGP) 9.5 negativity in those with NERD, and intraepithelial bleeding in those with RE. In addition, the combination of dilated intercellular spaces (DIS) (+)/PGP 9.5 (-) was indicative of strong resistance to PPI therapy in NERD patients.


CONCLUSION
The therapeutic efficacy of PPI can be predicted from the features of biopsied esophageal tissue. Factors predictive of resistance to treatment with PPI are negativity for PGP 9.5 in NERD patients and intraepithelial bleeding in RE patients.