Development of hydrogen excretion between feeds in breast and artificially fed full-term normal neonates

The breath hydrogen test for carbohydrate malabsorption has been proved to be sensitive, specific and noninvasive. This study was performed to determine its applicability in the newborn period. Postprandial hydrogen excretion in the first 5 days of life was measured in 105 full-term normal newborns, who were either artificially or breast fed. Samples of expired air were collected via a nasopharyngeal catheter at 30 min intervals between feeds. Some babies showed no hydrogen production after 5 days, while others produced high (200 parts/10(6] levels. The incidence of hydrogen production increased postnatally--more than 80% of babies produced hydrogen by 5 days of age. None of the babies was unwell or developed frequent or loose stools suggestive of clinical carbohydrate malabsorption. It is therefore postulated that these high hydrogen levels reflect biochemical evidence of clinically insignificant carbohydrate malabsorption in this age group. This study shows clearly that an interfeed interval of 4 h in these babies is insufficient to cause breath hydrogen levels to fall in a predictable way. The ethical and practical difficulties in fasting these infants for longer periods suggest that conventional carbohydrate challenges with breath hydrogen estimations will be difficult in the neonate.