Effect of an Amino Acid-based Milk—Neocate®—on Gastro-Oesophageal Reflux in Infants Assessed by Combined Intraluminal Impedance/pH

Cow's milk protein allergy-related gastro-oesophageal reflux (GOR) may be due to episodes of inappropriate lower oesophageal sphincter relaxation. The hypothetical physiological mechanism invoked to explain this involves a neurological consequence of the inflammatory infiltration induced from lamina propria vessels into the epithelial compartment. However, the efficacy of this approach has so examined with a physiologically-appropriate denominator to define the degree of GOR. We intend to conduct an investigation of the influence of Neocate® an amino acid-based milk, on GOR in infants by using a combined pH and intraluminal oesophageal impedance measurement. 11 infants (6 male, median age 151 days, range 75 to 345 days) bottle-fed with either expressed breast milk or formula milk, with symptoms clinically suggestive of GOR, underwent two 24-hour studies of intra-oesophageal 6 channel impedance and dual-channel pH monitoring before and 14 days after establishment on Neocate® amino acid formula. Impedance/ pH reflux data were recorded and analysed blind by one observer. Ten out of 11 infant's parents reported a decrease in the reflux score (p = 0.001). The median number of: reflux events/hour (1.58 vs. 1.68); acid reflux events/hour (0.26 vs. 0.43); minimum distal or proximal pH; total acid clearance time per hour (time with pH below pH 4); reflux height proximally up the oesophagus; and total reflux duration per hour were not statistically significantly different with presenting formula compared to that after 14 days ingestion of Neocate®. This trial reveals a symptomatic improvement on while Neocate®, but this improvement cannot be attributed to any positive effect on GOR as has been previously postulated. (Pediatr Asthma Allergy Immunol 2006; 19[4]:205–213.)