[Assessment of the lactose test and its value in detecting intolerance to milk sugar]

In 109 healthy and sick subjects suffering from diverse affections of the digestive organs the lactase activity in the mucosa of the large intestine was determined and a lactose test set up (1 g of lactose per 1 kg of body weight). In the test the following factors were considered: clinical symptoms, the rate of passage in the intestines (till the appearance of carmine), blood glucose content, pH and sugar in the feces. To appraise the activity of lactase the most accurate indicator in the test appeared to be the estimated degree of the rising blood glucose concentration as against the area of its ascent (23% of erroneous results). Because of a great variability of the test indicators the assessment of the lactase activity by combination of the latter did not increase the total number of correct results. However, in cases when there appeared combinations of indicators most characteristic for different activity of the lactase, the significance of the test results proved much higher (11.5-7% of erroneous results). Since in the lactose tolerance tests it is the total lactase activity, covering the entire surface of the small intestine that is recorded and subject to assessment are also possible changes, adaptive inclusive, of the gastro-intestinal tract motoricity, this test characterizes in the final analysis more correctly the tolerance of food products containing lactic sugar, than does direct determination of the lactase activity.