Thickening milk feeds may cause necrotising enterocolitis
Extremely low birthweight infants have the highest risk of developing necrotising enterocolitis (NEC). We report on two infants who developed fatal NEC while established on enteral feeds. A common antecedent was recent treatment with Carobel.
An 820 g boy and a 752 g girl, both of 25 weeks gestation, were fully established on enteral feeds with expressed breast milk by day 12 and 18 respectively. Non-specific symptoms were attributed to gastro-oesophageal reflux (GOR), which was empirically managed by thickening milk feeds. Instant Carobel (Cow & Gate) was started on postnatal day 12 and 24. Onset of NEC was day 26 and 30, with death one day later.
Carobel is unlicensed in the United Kingdom. The manufacturer advises that two to three level scoops may be added per 60–90 ml milk, but mentions no precautions or contraindications for preterm infants. Its use in preterm infants may have crept in since the withdrawal of cisapride in July 2000. Although feed thickening may reduce the frequency and volume of regurgitation, acid reflux remains unaffected, and a paradoxical increase in the occurrence of GOR has been described. Moreover, milk thickened with carob bean gum is less nutritive because of decreased bioavailability of essential elements.1 Two recent reviews found no evidence to support the practice of feed thickening in infants with GOR.2,3
We are concerned that carob thickened milk may have played a role in the demise of these infants. The exact pathophysiology could not be further investigated because neither infant underwent postmortem examination. Thickened feeds may have led to NEC as a result of bowel obstruction with subsequent bacterial overgrowth or following direct mucosal injury by calorific dense milk. Bacterial overgrowth is plausible because feed thickeners have been shown to significantly increase microbial population and enzyme activities in the weanling rat caecum.4 Enterocolitis has previously been reported in an infant secondary to feeds thickened with pectin and cellulose,5 as has neonatal intestinal obstruction and gastric lactobezoar.
Thickening feeds with carob bean gum is of unproven value in GOR. We feel that in preterm infants the practice may not be free from serious adverse effects and should not become widely adopted without a formal randomised trial.
