Research of congenital biliary atresia using analysis of DELTA^4-3-oxo-bile acids in urine

从新生儿到成人，尿Δ ^4 -3-氧代-胆汁酸的正常值均已确立。出生后，3-氧代-DELTA ^4-类固醇5 β-还原酶（5 β-还原酶）的活性立即增加，此后尿DELTA ^4 -3-氧代-胆汁酸逐渐减少，直至3个月大。然而，1岁后，我们再次检测到尿液中有少量的Δ ^4 -3-氧代-胆汁酸，Δ ^4 -3-氧代-胆汁酸是由肠道内的细菌植物群产生的，胆道闭锁患者尿液中Δ ^4 -3-氧代-胆汁酸占总胆汁酸（TBA）的百分比显著高于新生儿胆汁淤积或健康对照组（p<0.05）。然而，根据尿中TBA中Δ ^4 - 3-氧代胆汁酸的百分比，不能将胆道闭锁与特发性新生儿肝炎区分开来。和肝硬化显示这些患者表现出较高百分比的7 α-羟基-3-氧代喹啉-4-烯-24-酸和3-氧代喹啉-4，6-二烯-24-酸在TBA中比7 α，12 α-二羟基-3-氧代胆甾-4-烯-24-酸和12 α-羟基-3-氧代胆甾-4，6-二烯-24-酸更高。这些患者与预后不良呈正相关。这一发现表明，在5 β-还原酶活性的减少，由于严重的肝损伤导致减少12 α-hydroxylase.We报道的第一个日本患者与5 β-还原酶缺乏症在这项研究中。因此，确定肝病是原发性还是继发性5 β-还原酶缺乏症是非常重要的。总之，在肝病的早期阶段，确定异常尿胆汁酸（如Δ ^4 -3-氧代胆汁酸）的谱对于确定预后和/或治疗是很重要的。我们还认为，分析尿中的Δ ^4 -3-氧代胆汁酸对识别胆汁酸合成的先天性缺陷非常有用。

Normal values of urinary DELTA^4-3-oxo-bile acids were established in the present from neonates to adults. Activity of 3-oxo-DELTA^4-steroid 5beta-reductase (5beta-reductase) increased immediately after birth, and thereafter the urinary DELTA^4-3-oxo-bile acids gradually decreased until 3 months of age. However, after 1 year of age we again detected small amounts of DELTA^4-3-oxo-bile acids in the urine, DELTA^4-3-oxo-bile acids produced in the intestine by bacterial flora.The percentage of DELTA^4-3-oxo-bile acids in total bile acids (TBAs) in urine of biliary atresia significantly exceeded that of neonatal cholestasis or healthy controls (p<0.05). However, biliary atresia could not be distinguished from idiopathic neonatal hepatitis based on the percentage of DELTA^4-3-oxo-bile acids in TBAs in urine.In this study, moreover, analysis of DELTA^4-3-oxo-bile acids in patients with 5beta-reductase, fulminant hepatie failure, and cirrhosis showcd that these patients exhibited a higher percentage of 7alpha-hydroxy-3-oxochol-4-en-24-oic acid and 3-oxochola-4,6-dien-24-oic acid in TBAs than 7alpha, 12alpha-dihydroxy-3-oxochol-4-en-24-oic acid and 12alpha-hydroxy-3-oxochola-4,6-dien-24-oic acid. These patients were positively correlated with poor prognosis. This finding suggests that a reduction in 5beta-reductase activity due to severe liver damage leads to reduction in 12alpha-hydroxylase.We reported the first Japanese patient with 5beta-reductase deficiency during this study. It will very important to determine whether this disease should be defined as primary or secondary 5beta-reductase deficiency.In conclusion, to determine the profile of unusual urinary bile acids, such as DELTA^4-3-oxo-bile acids, at an early stage of liver disease is important to define prognosis and/or treatment. We also think that analysis of urinary DELTA^4-3-oxo-bile acids is very useful to identify inborn errors in bile acid synthesis.