Bile acid synthesis and excretion following release of total extrahepatic cholestasis by percutaneous transhepatic drainage

Abstract. Urinary, biliary and serum bile acids were studied in three patients before and after percutaneous transhepatic drainage for total bile duct obstruction.
Before drainage high urinary excretion often different bile acids occurred. The percentage distribution was: cholic and chenodeoxycholic acid (66–86%), hyo-cholic (3–16%), 3β 12α-dihydroxy-5-cholenoic (3–6%) and 3β-hydroxy-5-cholenoic acid (2–8%). These acids were regularly found in serum. In addition small amounts (less than 2%) of norcholic, allocholic, 3β, 7α-dihydroxy-5β-cholanoic, 3α, 7α-dihydroxy-5α-cholanoic and lithocholic acid were excreted in urine. Trace amounts of these bile acids were found in serum.
After start of drainage biliary bile acid excretion increased rapidly during the first day, dropped to a minimum during the second or third day and then slowly increased again. In spite of normal volumes of bile produced, the total serum bile acids and the urinary excretion of bile acids remained increased during a drainage period of 19 days. The bile acids were of the same type as observed during cholestasis. In serum the increase was mainly due to high concentrations of chenodeoxycholic and 3β-hydroxy-5-cholenoic acid, as sulphate esters.
Glycine and taurine conjugates of cholic, chenodeoxycholic and hyocholic acid were mainly excreted in bile. Bile acid sulphate esters were only present in trace amounts in bile and were mainly excreted in urine. This, combined with low renal clearance, explains the elevated serum levels of sulphate esters of chenodeoxycholic and 3β-hydroxy-5-cholenoic acid conjugates.