Purpose: Prednisolone is used routinely after portoenterostomy (PE) in patients with biliary atresia (BA).The authors reviewed their patients with BA post-PE to assess prednisolone protocols.Methods: Severity of fibrosis at PE (moderate or severe), age at PE (30-70 days), size of bile ductules in the fibrotic biliary remnant at the porta hepatis (>100 μm), and type of BA (uncorrectable type) were used as criteria for selecting 63 subjects from our patients with BA post-PE.Subjects were divided into 5 groups according to prednisolone dosage: group 1, no prednisolone; groups 2 to 4, single courses of intravenous prednisolone commencing on day 7 post-PE administered in decreasing dose for 3 days each as follows: group 2, 6, 4, and 2 mg; group 3, 10, 5, and 2.5 mg; group 4, 20, 15, 10, 5, and 2.5 mg; group 5, same as group 4, but stool color was used to monitor bile excretion and a course was restarted from 20 mg whenever stools began to turn pale.If necessary, single courses were repeated until serum total bilirubin was less than 2.0 mg/dL.Protocol efficacy was assessed by comparing the number of patients who became jaundice free, the period taken to become jaundice free, and the incidence of side effects related to prednisolone.Results: The number of patients who became jaundice free in the no prednisolone group (group 1, 7/12 or 58.3%) was not significantly different from the number in the single-course groups (group 2, 8/12 or 66.6%; group 3, 10/13 or 76.9%; and group 4, 11/15 or 73.3%).The number in the stool-monitored group (group 5, 10/11 or 90.9%) was significantly greater (P <.05).The mean period taken to become jaundice free in group 1 (82.6 ±29.1 days) was not significantly different from the single-course groups (group 2, 74.5 ±29.3 days; group 3, 49.6 ±19.8 days; and group 4, 48.3 ±26.0 days).The mean period taken in the stool-monitored group (group 5, 33.3 ±6.4 days) was significantly shorter (P <.05).The number of subjects who developed cholangitis after becoming jaundice free was not significantly different (group 1, 2/7; group 2, 2/8; group 3, 2/10; group 4, 2/11; group 5, 2/10).There were no prednisolone-related complications identified in any subject.Conclusions: These results provide strong evidence that large-dose prednisolone therapy with stool color monitoring of bile flow has a positive impact on the time taken for patients with BA post-PE to become jaundice free and the number of patients who remain jaundice free. Purposes: Prednisolone is used routinely after portoenterostomy (PE) in patients with biliary atresia (BA). The authors reviewed their patients with BA post-PE to assess prednisolone protocols. Methods: Severity of fibrosis at PE (moderate or severe), age at PE (30-70 days), size of bile ductules in the fibrotic biliary remnant at the porta hepatis (> 100 μm), and type of BA (uncorrectable type) were used as criteria for selecting 63 subjects from our patients with BA post- PE. Subjects were divided into 5 groups according to prednisolone dosage: group 1, no prednisolone; groups 2 to 4, single courses of intravenous prednisolone commencing on day 7 post-PE administered in decreasing dose for 3 days each as follows: group 2, Group 4, 20, 15, 10, 5, and 2.5 mg; group 5, same as group 4, but stool color was used to monitor bile excretion and a course was restarted from 20 mg whenever stools began to turn pale.If necessary, single courses were repeate d until serum total bilirubin was less than 2.0 mg / dL. Protocols efficacy was comparing by the number of patients who became jaundice free, the period taken to become jaundice free, and the incidence of side effects related to prednisolone. Results: The number of patients who became jaundice free in the no prednisolone group (group 1, 7/12 or 58.3%) was not significantly different from the number in the single-course groups (group 2, 8/12 or 66.6%; group 3, 10 / 13 or 76.9%; and group 4, 11/15 or 73.3%). The number in the stool-monitored group (group 5, 10/11 or 90.9%) was significantly greater (P <.05) taken to become jaundice free in group 1 (82.6 ± 29.1 days) was not significantly different from the single-course groups (group 2, 74.5 ± 29.3 days; group 3, 49.6 ± 19.8 days; and group 4, 48.3 ± 26.0 days) The mean period taken in the stool-monitored group (group 5, 33.3 ± 6.4 days) was significantly shorter (P <.05). The number of subjects who developed cholangitis afterbecome jaundice free was not significantly different (group 1, 2/7; group 2, 2/8; group 3, 2/10; group 4, 2/11; group 5, 2/10) .There were no prednisolone-related complications identified in any subject.Conclusions: These results provide strong strong that that large-dose prednisolone therapy with stool color monitoring of bile flow has a positive impact on the time taken for patients with BA post-PE to become jaundice free and the number of patients who remain jaundice free.