Changes in enzyme activity in normal and histologically inflamed oesophageal epithelium

Oesophageal biopsies were obtained from 74 patinets undergoing upper gastrointestinal fibreoptic endoscopy. Thirteen patients with histological evidence of inflammation had a raised alkaline phosphatase activity (2.7 +/- 1.6 nmol/mg protein/min) compared with 49 normal controls (1.2 +/- 0.68 nmol/mg protein/min: P less than 0.001). The acid phosphatase level was lower (8.4+/- 4.0 vs. 5.8 +/- 2.2 nmol/mg protein/min: P less than 0.05) and the glucuronidase activity raised (0.44 +/- 0.17 vs 0.81 +/- 0.32 nmol/mg protein/min: P less than 0.001) and their ratio declined (24.0 +/- 1.9 nmol/mg protein/min: P less than 0.001) in patients with oesophagitis. This may be due to differential secretion of membrane coating granules, a form of lysosome found isophagitis--was assessed by point counting. The volume density rose from 10.9 +/- 4.25% in normal biopsies to 46.4+/-12.5% (P less than 0.001) in oesophagitis. These results show a consistent pattern that possibly indicates an intermediate stage between the clinically, histologically, and biochemically normal oesophagus and one that is inflamed on endoscopy.