Radionuclide scintigraphy in the evaluation of gastroesophageal reflux in symptomatic and asymptomatic pre-term infants

Abstract

Purpose: Gastroesophageal reflux (GER) is very common in pre-term infants. The diagnosis based on symptoms is always questionable. The incidence of GER in symptomatic babies varies from 22% to 85%, but literature regarding the incidence of reflux in asymptomatic pre-term infants is lacking. We used radionuclide scintigraphy to evaluate the incidence of GER in symptomatic as well as asymptomatic pre-term neonates and to assess whether symptoms have any relation with positive scintigraphy. Methods: We studied 106 pre-term infants (52 symptomatic, 54 asymptomatic) of less than 34 weeks of gestation, who fulfilled the eligibility criteria. Babies were considered symptomatic in the presence of vomiting, regurgitation, apnea, de-saturations, unexplained bradycardia and recurrent lung collapses. Radionuclide scintigraphy was conducted at post-conceptional age of 32-34 weeks when they were clinically stable for 72 h. Feeding was avoided for 2 h preceding the study. 99mTc sulphur colloid was administered in a dose of 1.85 MBq (0.05 mCi) in 1 ml, followed by milk (full feed) through an orogastric tube, prior to imaging under a gamma camera. Reflux was graded as low or high, and reflux episodes during the study were counted. Results: The incidence of GER in the symptomatic group was 71.2% and in asymptomatic babies 61.1% (p=0.275). High-grade reflux was more common (71.4%) than low-grade (28.6%) in both groups (p=0.449). Mean number of reflux episodes in 20 min was 4.4±2.4 in symptomatic babies and 4.9±2.2 in asymptomatic babies (p=0.321). Babies with positive scintigraphy were similar in birth weight, gestation, time to achieve full feeds, weight and age at discharge to those with negative scintigraphy. Conclusions: GER is common in pre-term infants of less than 34 weeks gestation. The incidence of positive scintigraphy and grade of reflux is not significantly different in symptomatic vs. asymptomatic babies. Though radionuclide scintigraphy is a simple, quick and non-invasive investigation in suspected cases of GER, positive scintigraphy has no correlation with symptoms. © 2008 Springer-Verlag.