Abnormal colonic motility in progressive systemic sclerosis.

Progressive systemic sclerosis alters smooth muscle function throughout the gastrointestinal tract. In 10 consecutive patients with the disease, colonic spike activity and contractile activity were measured after a 1000-kcal meal, intramuscular injection of neostigmine, or intravenous injection of metoclopramide. The 1000-kcal meal stimulated a significant increase in spike and contractile activity in normal subjects. Nine of the 10 patients had no increase in motility after eating. Neostigmine or metoclopramide stimulated colonic spike (p less than 0.01) and contractile (p less than 0.02) activity in normal subjects and stimulated colonic motility (p less than 0.01) in four of 10 patients with less severe systemic manifestations of the disease (Group 1). The drugs had no effect on patients with severe progressive systemic sclerosis (Group II). The patients with severe scleroderma had significant gastrointestinal roentgenographic abnormalities and severe cardiac, renal, or pulmonary dysfunction. Four of six Group II patients died from the disease; all four had marked smooth muscle atrophy in the colonic wall. These findings suggest that the gastrocolonic response is absent early in the disease process and that the smooth muscle atrophy occurring with progression of the disease may lead to a more severe colonic motor disturbance.