Hyperglycaemia attenuates erythromycin-induced acceleration of solid-phasegastric emptying in idiopathic and diabetic gastroparesis

Background: Erythromycin has recently been found to be a gastrointestinal p rokinetic agent in humans. Acute hyperglycaemia has been associated with de layed gastric emptying in both healthy controls and diabetic patients. Our aim was to investigate in gastroparetic patients (diabetics and idiopathies ) whether hyperglycaemia, per se, reduces gastric motility during erythromy cin-induced acceleration of gastric emptying of solids, Methods: In 12 gast roparetic patients, 6 diabetics and 6 idiopathies, gastric emptying of soli ds was measured scintigraphically after giving placebo in normoglycaemia (5 -8.9 mmol/l glucose) or 200 mg erythromycin lactobionate intravenously in n ormo- or hyperglycaemia (16-19 mmol/l glucose) induced by intravenous gluco se infusion in random order on separate days. Results: Erythromycin in norm oglycaemia accelerated solids gastric emptying compared with placebo in all patients by abolishing the lag-phase duration and by decreasing the retain ed percentage of a meal in the stomach at 120 and 150 min (14.5% +/- 5.3% v ersus 88.4% +/- 10.6% and 3.5% +/- 2.1% versus 70.1% +/- 15.4%, respectivel y) (P < 0.001). The retained isotopic percentage in the stomach after eryth romycin in induced hyperglycaemia compared with erythromycin in normoglycae mia, at 120 and 150 min, was increased (51.9% +/- 9.8% versus 14.5% +/- 5.3 % and 24.5% +/- 5.9% versus 3.5% +/- 2.1%, respectively) (P < 0.001) but wa s decreased in comparison with placebo (P < 0.001). A significantly increas ed percentage of isotope was retained in the stomach of the diabetic patien ts at 110 and 150 min, compared with the idiopathies, only after giving ery thromycin in the hyperglycaemic condition (57.6% +/- 8.7% versus 46.1% +/- 7.6% (P = 0.036) and 27.8% +/- 5.7% versus 21.1 +/- 4.4% (P = 0.040), respe ctively). Conclusions: Hyperglycaemia attenuates erythromycin-induced accel eration of solid-phase gastric emptying in idiopathic and diabetic gastropa resis and increases the retained isotopic meal in the stomach. Hyperglycaem ia reduces gastric motility more in the diabetic patients with gastroparesi s than in idiopathic patients.