Disaccharidases in coeliac disease.

In 30 children presenting with complaints characteristic of malabsorption in whom congenital enzyme deficiency could be excluded, determination of the enzymes lactase, saccharase and maltase was performed in the tissue sample obtained by jejunal biopsy; histology was also carried out in all cases. In 23 cases the diagnosis of coeliac disease could subsequently be confirmed, in the other 7 cases the diagnosis could neither be rejected nor established with certainty. All three enzymes had a decreased activity in cases displaying subtotal or total villous atrophy, the most sensitive among them being lactase: in 69% of cases no lactase activity could be shown while saccharase and maltase were absent in 29 respectively 4% of the cases. No close correlation exists between the light-microscopic findings and the activity of enzymes since total absence of enzyme activity may be associated with only moderate villous atrophy. Lack of disaccharidase activity in the upper section of the small bowel does not necessarily mean disaccharide malabsorption exhibiting clinical symptoms, it only indicates a reduced capacity of disaccharide splitting. It has been concluded that routine determination of disaccharidase activities is not justified within the diagnostic procedure of coeliac disease.