Antroduodenal motor effects of intravenous erythromycin in children with abnormalities of gastrointestinal motility

Background: The macrolide antibiotic erythromycin (EM) affects gastrointestinal motor activity by acting as agonist of motilin receptors located on the smooth muscle cells of the gastroduodenal tract. We studied the effect of intravenous EM on fasting antroduodenal motility in controls and children with gastrointestinal dysmotility. Methods: EM lactobionate (rate, 3.0 mg/kg/h) was infused intravenously while antroduodenal manometry was recorded in 10 controls, in 7 patients with functional dyspepsia and in 6 patients with gut pseudo-obstruction. The mean (SD) age (years) was 5.7 (1.4), 6.5 (2.4), and 6.7 (3.2), respectively. Manometry was performed by means of a four- or six-lumen catheter introduced through the nose and perfused with a low compliance pneumohydraulic system. Five controls received EM and five received saline. Results: EM, infused 5 minutes after passage of an activity front (AF), induced in controls a premature antroduodenal AF occurring 15.4 +/- 3.2 minutes after starting infusion; no motor changes were seen after saline; duration and propagation velocity of EM-induced AFs did not differ from spontaneous AFs. In patients with functional dyspepsia EM induced various patterns such as premature antroduodenal AFs, antral phase III-like pattern with short duodenal bursts or prolonged phasic antral waves and no duodenal activity. In patients with neurogenic pseudoobstruction rare or absent antral activity with incoordinated or absent duodenal activity was induced; no contractions were elicited in two patients with myogenic pseudo-obstruction. Conclusions: It is confirmed that EM, given at subtherapeutic doses, is a powerful prokinetic agent that can have clinical applications in patients with gastrointestinal dysmotility; however, the effect of the drug seems to be influenced by the nature of the underlying disorder.