Elevated Serum Bone Morphogenetic Protein 7 Levels and Clinical Outcome in Children with Biliary Atresia

Abstract

Background and Aim: Biliary atresia (BA) is one of the most serious liver disorders in children. The purposes of the present study were to investigate serum levels of bone morphogenetic protein 7 (BMP7) in BA children compared with healthy controls and to evaluate the association between serum BMP7 and the clinical outcome of BA patients post Kasai operation.

Methods: Sixty-two BA patients post Kasai operation and 14 healthy controls were enrolled. The patients were divided into two groups according to their serum total bilirubin levels (TB<2, no jaundice vs. TB≥2 mg/dL, persistent jaundice) and alanine aminotransferase levels (ALT<45, normal ALT vs. ALT≥45 IU/L, elevated ALT). Serum BMP7 levels were determined by commercial enzyme-linked immunoabsorbent assay.

Results: The mean serum BMP7 was higher in BA patients compared with that of healthy controls (35.4±3.6 vs. 20.6±2.7 pg/mL, p=0.002). The BA patients with persistent jaundice had more elevated serum BMP7 levels than those without jaundice (59.5±6.5 vs. 20.3±1.6 pg/mL, p=0.001). There was also a correlation between serum total bilirubin and serum BMP7 levels (r=0.57, p<0.001). Moreover, the levels of serum BMP7 in BA patients with elevated ALT were significantly higher than those with normal ALT (41.6±4.7 vs. 22.4±4.2 pg/mL, p=0.003). Additionally, BA patients with portal hypertension had higher increased serum BMP7 levels compared to those without portal hypertension (45.3±4.9 vs. 18.7±2.8 pg/mL, p<0.001).

Conclusion: The significant increment of serum BMP7 was associated with a deterioration of hepatic function and the progression of liver fibrosis. Serum BMP7 could be used as a prognostic marker to reflect disease severity and monitor disease progression in BA patients post Kasai operation.

Key words

biliary atresia - BMP7 - clinical outcome - jaundice

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