Effect of octreotide on intestinal motility and bacterial overgrowth in scleroderma

Patients with scleroderma may have abnormal motility of the small intestine, with pseudoobstruction and bacterial overgrowth. Standard stimulatory agents are often ineffective in such patients. Because the somatostatin analogue octreotide evokes intestinal motor activity in normal subjects, we hypothesized that it might increase motility in patients with scleroderma.

We studied the effects of octreotide on intestinal motility and plasma motilin concentrations in five fasting patients with scleroderma who had bacterial overgrowth and in six fasting normal subjects. The motor effects of octreotide were correlated with its effects on abdominal symptoms and bacterial overgrowth as determined by the level of breath hydrogen excretion.

In the normal subjects, octreotide (10 micrograms subcutaneously) increased the mean (+/- SD) frequency of intestinal migrating complexes, which reflect intestinal motility, from 1.5 +/- 1.0 to 4.1 +/- 1.1 every three hours. In the patients with scleroderma, who had no spontaneous migrating complexes, octreotide (100 micrograms) induced 3.6 +/- 2.3 complexes every three hours. These complexes propagated at the same velocity and had two-thirds the amplitude of the spontaneous complexes in normal subjects. Plasma motilin concentrations, which were higher in the patients with scleroderma (229 +/- 74 pmol per liter) than in the normal subjects (112 +/- 37 pmol per liter), were inhibited by octreotide, suggesting that intestinal activity evoked by octreotide is independent of motilin. Treatment of the patients with scleroderma with octreotide (50 micrograms every evening) for three weeks reduced breath hydrogen excretion while they were fasting from 25 +/- 5 to 4 +/- 2 ppm (P = 0.001) and breath hydrogen excretion after they ingested 50 g of glucose from 46 +/- 24 to 8 +/- 7 ppm (P = 0.015); these reductions were accompanied by a significant decrease in nausea, bloating, and abdominal pain and by less frequent emesis.

Octreotide stimulates intestinal motility in normal subjects and in patients with scleroderma. In such patients, the short-term administration of octreotide reduces bacterial overgrowth and improves abdominal symptoms. This agent may be useful for the treatment of intestinal dysmotility in patients with scleroderma.