Measurement and demonstration of lactase and sucrase activities in jejunal mucosa.

Jejunal lactase and sucrase activities were demonstrated on endoscopically obtained biopsy specimens by a rapid test which had been developed earlier. The results were compared with enzyme activities found by Dahlquist's method. The data suggest that the rapid test is suitable for the semiquantitative determination of lactase and sucrase, and the results correlate with enzyme activities measured by the Dahlquist assay. The main advantage of the test is that it is rapid, simple, and cheap, and because no special equipment is necessary, it can be used in any endoscopic department.