肠外营养相关性肝病婴儿碱性磷酸酶升高更反映骨病而非肝病

　　背景：肠衰竭（IF）婴儿血清碱性磷酸酶（ALP）升高可能由肠外营养相关性肝病（PNALD）或代谢性骨病（MBD）引起。本研究旨在通过检测IF和PNALD婴儿组织特异性ALP水平，明确血清ALP用于PNALD诊断标准的效用。

　　方法：我们对2012年12月至2013年8月期间被诊断为PNALD的15例婴儿的病历资料进行了回顾性分析。当存在连续2次血清直接胆红素（DB）水平＞2mg/dL即被诊断为PNALD。当DB＞2mg/dL时，检测婴儿血清ALP组织亚型。尽可能记录甲状旁腺素（PTH）、维生素D3、钙以及磷酸盐水平的数据。

　　结果：在15例PNALD婴儿中，ALP总水平升高是因为骨组织特异性ALP升高。肝特异性ALP中位数仍维持在正常范围之内。PTH、维生素D3、钙以及磷酸盐水平均在正常界限内。

　　结论：虽然ALP升高可以反映胆汁淤积，但在IF和PNALD婴儿中，ALP升高主要为骨源性而非肝源性。因此，当PNALD婴儿ALP升高时，应怀疑潜在骨病而非仅仅归因于肝病。

JPEN J Parenter Enteral Nutr. 2015;39(8):973-6.

Elevated Alkaline Phosphatase in Infants With Parenteral Nutrition-Associated Liver Disease Reflects Bone Rather Than Liver Disease.

Nandivada P, Potemkin AK, Carlson SJ, Chang MI, Cowan E, O'Loughlin AA, Gura KM, Puder M.

Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.

BACKGROUND: Elevated serum alkaline phosphatase (ALP) in infants with intestinal failure (IF) can be due to parenteral nutrition-associated liver disease (PNALD) or metabolic bone disease (MBD). The purpose of the study was to determine the utility of serum ALP in the diagnostic criteria for PNALD by measuring tissue-specific levels in infants with IF and PNALD.

METHODS: A retrospective review of patient data for 15 infants diagnosed with PNALD between December 2012 and August 2013 was performed. PNALD was defined as the presence of 2 consecutive direct bilirubin (DB) levels >2 mg/dL. Fractionated serum alkaline phosphatase was measured in each patient, while the DB was >2 mg/dL. Parathyroid hormone (PTH), vitamin D3, calcium, and phosphate levels were recorded where available.

RESULTS: In 15 infants with PNALD, elevation in total ALP was due to marked elevations in bone-specific ALP. The median liver-specific ALP remained within the normal range. PTH, vitamin D3, calcium, and phosphate levels were within normal limits.

CONCLUSION: While elevated ALP can reflect biliary stasis, the ALP elevation observed in infants with IF and PNALD is predominantly of bone rather than hepatic origin. An elevated unfractionated ALP in infants with PNALD should therefore raise suspicion of underlying bone disease, rather than being attributed to liver disease alone.

KEYWORDS: gastroenterology; life cycle; neonates; nutrition; parenteral nutrition; research and diseases

PMID: 25106918

DOI: 10.1177/0148607114545995