Azithromycin Induces Migrating Motor Complexes in Pediatric Patients Undergoing Antroduodenal Motility Studies

Abstract

OBJECTIVE Erythromycin (ERY) is used in the treatment of gastroparesis; however, this medication is associated with serious side effects, such as cardiac arrhythmias and consequent cardiorespiratory arrest. Azithromycin (AZM) has been suggested as an alternative to ERY as a result of its improved safety profile. Intravenous ERY (1 mg/kg) is administered during antroduodenal motility studies to induce migrating motor complexes (MMCs), the presence or absence of which helps diagnose motility disorders like gastroparesis and gastrointestinal dysmotility. However, there are no pediatric studies comparing the effects of AZM and ERY on antroduodenal pressure profiles. The goal of this study is to determine if AZM is comparable in inducing MMCs in pediatric patients undergoing antroduodenal motility studies. METHODS We performed a retrospective chart analysis of gastric and small bowel manometric data in 2 adolescent patients, both age 15 years, who were given AZM (1 mg/kg) during antroduodenal motility studies. The pressure profiles obtained during motility studies were compared to those of patients of similar age and symptomology who were given the standard intravenous ERY dose during motility studies. We then compared the total duration of effect, mean amplitude of contractions, number of cycles per minute, and duration of highest antral and duodenal contractions. RESULTS Intravenous AZM induces migrating motor contractions in the stomach followed by contractions in the small intestine. The mean amplitude of the stomach contractions was 259 mm Hg in patients who received AZM vs 241 mm Hg in patients who received ERY. The mean amplitude of small intestinal MMCs was 68 mm Hg in patients who received AZI and 72 mm Hg in patients who received ERY. Additionally, the frequency and duration of stomach and small intestinal contractions were also similar in the 2 groups. CONCLUSIONS Intravenous AZM has similar prokinetic effects to intravenous ERY. Our study suggests that AZM is a suitable alternative to ERY in inducing MMCs without the concerning side effects related to ERY and may potentially be used in the management of gastroparesis and other small bowel motility disorders. However, larger prospective studies are required to better understand the long-term efficacy of AZM.

Comparative Effectiveness of Intravenous Azithromycin Versus Erythromycin Stimulating Antroduodenal Motility in Children

“…Like ERY, AZM can bind to the motilin receptor, resulting in a concentration-dependent increase in intracellular calcium and stimulation of cholinergic mediated smooth muscle contractions in adults to a level comparable to ERY (11,22,23); however, AZM and ERY have different pharmacodynamic and pharmacokinetic profiles, resulting in non-equivalent recommended dosing (24,25). AZM has a large volume of distribution (23 L/kg) and low peak serum level (0.4 mg/mL), demonstrating extensive tissue distribution and intracellular accumulation.…”

“…There is data in adults comparing the use of AZM with ERY during antroduodenal manometry (7). To date, published studies that examine the effectiveness of AZM as an alternative to ERY for prokinetic therapy in children are scarce and have examined only small numbers of patients (11). Due to an interruption in the supply of intravenous ERY, we were forced to turn to AZM as an alternative to ERY for pediatric ADM.…”

“…Intestinal obstruction was ruled out in all patients with a history of GI surgery. Patients underwent ADM as a part of the diagnostic workup, using a protocol that was adapted from previously published studies (9,11). Patients were asked to stop taking medications that alter GI motility, such as prokinetics and anticholinergics, three days before the study.…”

Effects of Provocative Testing on Phase III Migrating Motor Complex in Children

“…We used intravenous azithromycin in our protocol due to the shortage of erythromycin during the study period. Azithromycin has also been used as a provocative agent during ADM study and shown to have similar effects as erythromycin (22–24). Our data revealed fewer phase III MMC induced by azithromycin compared to the previously reported.…”