Brush border enzyme activities in relation to histological lesion in pediatric celiac disease

In celiac disease (CD), abnormalities of brush border enzyme activities have been detected in the course of the disease activity. There are conflicting results on intestinal mucosal enzyme activities and its correlation to mucosal injury in CD. The aim of the present study was to evaluate the brush border enzyme activities (disaccharidases and alkaline phosphatase) in the duodenal mucosa of North Indian children with CD and to examine their correlation to duodenal mucosal morphological alterations.

This prospective study included 71 children with CD and 29 controls (patients with gastroesophageal reflux disease) in whom upper gastrointestinal endoscopy was performed and distal duodenal biopsies were taken for histological assessment, and estimation of disaccharidases and alkaline phosphatase activities. Each biopsy sample was classified according to the modified Oberhuber classification. Lactase, sucrase, maltase and alkaline phosphatase activities were estimated in duodenal biopsy homogenates from patients with CD and from controls. The association between enzyme activities and duodenal morphology was examined.

The mean age of the 71 patients with CD (M:F, 43:28) was 6.0 +/- 0.3 years and mean age of onset of symptoms was 2.7 +/- 0.4 years. Sixty-four of 71 (90.1%) CD patients showed type 3 (destructive) lesion, whereas it was grade 0 in all patients with gastroesophageal reflux disease. In CD and patients with gastroesophageal reflux disease, the mean level (IU/g protein) of lactase was 12.1 +/- 0.9 versus 24.4 +/- 1.0 (P < 0.001), mean level of sucrase was 25.9 +/- 1.9 versus 42.5 +/- 1.9 (P < 0.001), mean level of maltase was 56.6 +/- 3.5 versus 76.1 +/- 13.0 (NS), and mean level of alkaline phosphatase was 602.8 +/- 56.2 versus 1359.3 +/- 51.2 (P < 0.001), respectively. The mean disaccharidases and alkaline phosphatase levels were not significantly different in patients with milder lesions (type 2 and type 3a) compared with those of control. However, mean lactase, sucrase and alkaline phosphatase levels were significantly lower (P < 0.001) in CD patients with moderate (type 3b) and severe (type 3c) lesions compared with control.

A generalized decrease of disaccharidases and alkaline phosphatase activity was seen in the duodenal mucosa of children with CD. The depressed activities of lactase, sucrase and alkaline phosphatase were well correlated with the histological grade of duodenal mucosal lesions in children with CD.