Disaccharidase activities in small intestinal mucosa in patients with cystic fibrosis.

The disaccharidase activities in small intestinal biopsies were related to the morphology 
of the mucosa and the ages of 63 patients with cystic 
fibrosis and 177 healthy control subjects of Caucasian origin. In patients 
with CF and in the healthy control subjects under 5 years 
of age with normal intestinal mucosa, no low lactase activity was 
found. In those patients with CF who were over 5 years 
of age, one group had high and one group had low 
lactase activity, as occurs in healthy Caucasian control subjects of the 
same age. This finding supports the view that in patients with 
CF, lactase deficiency is not related to the disease entity. In 
patients with or without CF who had the same degree of 
mucosal atrophy, the decrease of disaccharidase activities followed the same pattern, 
indicating that enzyme activities are affected to the same extent by 
the damage of the mucosa. In patients with CF with pancreatic 
insufficiency, the disaccharidase activities were significantly (P less than 0.001) higher 
when compared to those in control subjects of the same age 
and ethnic group, although the increase was not uniform in all 
patients with cystic fibrosis. 