An activating gucy2c mutation causes impaired contractility and fluid stagnation in the small bowel

AbstractObjective: Familial GUCY2C diarrhoea syndrome (FGDS) is caused by an activating mutation in the GUCY2C gene encoding the receptor guanylate cyclase C in enterocytes. Activation leads to increased secretion of fluid into the intestinal lumen. Twenty percent of the patients have increased risk of Crohn’s disease and intestinal obstruction (CD, 20%) and the condition resembles irritable bowel syndrome with diarrhoea. We aimed to describe fluid content, contractility, peristaltic activity and bowel wall thickness in the intestine in fasting FGDS patients, using ultrasound, with healthy volunteers serving as controls.Methods: Twenty-three patients with FGDS and 22 healthy controls (HC) were examined with a Logiq E9 scanner in a fasting state. Bowel wall thickness was measured and fluid-filled small bowel loops were counted using three-dimensional (3D) magnetic positioning navigation. The HC ingested 500 ml PEG solution, an electrolyte balanced, non-absorbable solution, in order to investigate the contr...