Measurement of serum total bile acid levels in long-term postoperative follow-up of patients with congenital bile-duct dilatation.

Serum total bile acid levels (STBA), a sensitive indicator of cholestasis, were measured during the long-term postoperative period in patients with congenital bile-duct dilatation (CBDD) (choledochal cyst) and the factors contributing to elevation of STBA were analyzed in 44 patients. Their ages at operation ranged from 1 month to 16 years. A STBA level over 12 nmol/ml on two or more measurements during outpatient follow-up was considered abnormal. Patients were classified into three groups: group 1, STBA, 12-50 nmol/ml; group 2, STBA > or = 50 nmol/ml; group N, STBA normal. In 19 patients (43.2%) STBA was normal. Of the 25 patients (56.8%) with elevated STBA, groups 1 and 2 comprised 12 (27.3%) and 13 patients (29.5%), respectively. The mean age in group N was 5.1 +/- 4.2 years, which was higher than in groups 1 (2.6 +/- 2.3) and 2 (2.3 +/- 2.5 years) ( P< 0.05). Preoperative STBA and total bilirubin were higher in group 2 (79.2 +/- 75.1 nmol/ml resp. 5.2 +/- 4.2 mg/dl) than in groups N (20.1 +/- 32.6, 1.3 +/- 1.4) and 1 (22.8 +/- 37.2, 1.4 +/- 1.0) ( P< 0.05). Preoperative alkaline phosphatase and gamma-glutamyl transpeptidase were higher in group 2 (1,006 +/- 872 IU/l, 452 +/- 326 IU/l) than in group N (573 +/- 371, 205 +/- 238) ( P< 0.05). Histologic findings on liver biopsy showed fibrosis in 38.5% of group 2 patients, which was significantly higher than in groups N (15.8%) and 1 (16.7%) ( P< 0.05). Cholestasis was detected in 41.7% of group 1 and 61.5% of group 2 patients, compared to 10.5% of group N patients ( P< 0.05). Postoperative elevation of STBA may thus persist in more than one-half of patients with CBDD, and is likely to occur in patients of young age who have severe cholestasis or liver fibrosis preoperatively. Further investigations may be required in regard to the development of postoperative complications.