Abstracts: 38th Annual Meeting of the European Society for Pediatric Gastroentrology, Hepatology and Nutrition: Porto, Portugal, June 1-4, 2005
Previous in vivo studies (1) have shown that unconjugated bilirubin may be responsible for an increase of intestinal permeability (IP). This can be relevant for neonatal health. Aim of the study is to investigate the effects of unconjugated bilirubin on intestinal permeability of healthy, term neonates.
IP was measured by the sugar absorption test (SAT) performed at the third day of life in 12 healthy term jaundiced AGA newborns (total bilirubin >13 mg/dl) and compared to that of 12 healthy term non-jaundiced AGA newborns (total bilirubin <8 mg/dl) matched for sex, GA, birth weight and Apgar score. In the SAT, the urinary lactulose/mannitol ratio (La/Ma) was measured after oral ingestion of a solution containing 86 mg of lactulose (La) and 1.4 mg of mannitol (Ma) per 1 ml water at a dose of 2 ml/kg. Urine was then collected for five hours, La and Ma concentrations were measured by HPLC (high liquid phase chromatography) (mg/l) and La/Ma calculated.
Jaundiced newborns have a significantly higher La/Ma than non-jaundiced [mean 0.31 (sd ± 0.28) vs. mean 0.054 (sd ± 0.04)]. A significant correlation was found between hyperbilirubinemia and La/Ma (r2 = 0.526 p = 0.008).
This first pilot clinical study shows that hyperbilirubinemia is responsible for an increase of IP in term, healthy newborns with uncomplicated jaundice.
We speculate that such an increase of IP may facilitate the passage of food allergens through the intestinal epithelial barrier. Further studies are needed to detect the underlying mechanisms of this liaison.
(1) Jaerhrig K, Balke EH, Koenig A, Meisel P, Transepithelial electric potential difference in newborns undergoing phototherapy. Ped Res