LACK OF STIMULATION OF SUCRASE AND ISOMALTASE WITH FRUCTOSE IN CHILDREN WITH SUCROSE-ISOMALTOSE MALABSORPTION |[lpar]|S-IM|[rpar

Abstract

Top of pageAbstract In normal adults fructose stimulates the activity of sucrase and maltase. In a single patient with S-IM Greene et al. (1) found an increase in the sucrase activity after fructose ingestion (~ 40-60% of the caloric intake (c.i.)) and suggested dietary fructose as a form of therapy to these patients. In order to elucidate this possibility we have by methods earlier described (2) investigated the activity and rocket immunoelectrophoretic pattern of the dissaccharidasis in small intestinal biopsies from 2 children with S-IM (age 13 and 16 yrs) before and 2 weeks after a daily intake of an otherwise isocaloric diet containing 300 g of fructose (~50% of c.i.). Before the diet both children showed a sucrase activity below detection level (1 U/g prot.) and a residual isomaltase activity of 7, 9 and 2, 9 U/g prot., respectively. After the diet there was still no sucrase activity and the changes in the in the isomaltase level were not significant. The immunoelectrophoretic studies were in complete concordance with these findings. In conclusion even a very high dietary supplement with fructose can not initiate an increase of the missing enzymes in S-IM and represents no therapeutic alternative. (1) Greene, H L et al. Biochem Med 1972; 6: 409. (2) Skovbjerg, H, Krasilnikoff, P A. Pediatr. Res 1981; 15: 214.