Diagnosis and Management of Biliary Atresia
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THOMSON gave the first accurate description of the natural history of biliary atresia in 1892. During the following 67 years the condition was generally considered to be untreatable although a few rare cases, in which there was a residual segment of patent proximal bile duct, were corrected by hepatico-jejunostomy. Kasai l959), was the first to recognise that excision of the atretic bile ducts in the porta hepatis could result in bile flow. He described the operation of portoerterostomy in which a loop of jejunum is anastomosed to the devided bile duct tissue or the under surface of the liver. He also demonstrated that satisfactory bile flow was achieved more frequently if operation performed before 6 or 7 weeks of age. However, the world results of surgery between 1965and 1975 remained very poor. A survey of 539 cases from 11 centres in Australia, Europe, Japan and USA in 1977 revealed that corrective surgery had been performed in 381 children and that there were only 67 survivors, (17.7%), (Carcassonne and Bensoussan, 1977). For a few years there was vigorous debate of effectiveness, or otherwise, of portoenterostomy, but after 1975 the results gradually improved.
It is no agreed that early diagnosis within the first few weeks of lf is essential for satisfactory surgical results. Affected infants present with conjugated hyperbilirubinaemia, dark urine and pale acholic stools and a few present with abnormal bleeding secondary to vitamin K malabsorption. Recently a number of cases have been diagnosed on prenatal ultras sound scans (Redkar et al 1998). Liver biochemistry in the jaundiced infant is non-specific and does not differentiate atresia from other cause s of prolonged neonatal jaundice such as neonatal hepatitis. Radionuclide hepatobiliary imaging shows an absence of biliary excretion cases of atresia and abdominal ultrasound will exclude other causes of jaundice such as choledochal cyst. Percutaneous liver biopsy is diagnostic in approximately 85% of cases. If the diagnosis remains unclear then endoscopic retrograde cholangiography is used in centres with access to this technique.
There have been no large-scale randomized trials to determine the effectiveness of these various regimens. For example steroids have been used frequently but a small study by Karrer and Lily (1985), suggested that although steroids increased the volumes of bile drainage, the total excretion of bilirubin remained constant. There was no significant difference in this study between a group of patients treated with, and a group treated without, steroids. Currently we advise a month of post operative treatment with a broad-spectrum antibiotic, and long-term treatment with phenobarbitone, vitamin K and multivitamin supplements.
Ascending bacterial cholangitis occurs most frequently in the first ye- after portoenterostomy. Infection is confirmed with blood culture or per-cutaneous liver biopsy and culture and treatment is with an intravenou. broadspectrurn antibiotic. Roux loop obstruction should be excluded as a cause of cholangitis in an older infant or child who has previously, well and anicteric for a long period of time.
Portal hypertension is a common finding in long-term portoenterostomy survivors, and oesophageal varices are visible on endoscopy of the patients after 2 years of age. Endoscopic sclerotherapy, or variceal banding, is generally successful in controlling variceal hemorrhage. More recently, transjugular intrahepatic portosystemic shunt procedure have been used before liver transplantation in patients with portal hypertention secondary to advanced cirrhosis. Severe portal hypertension an anicteric child is a difficult problem although it can now be regard as one of the indications for transplantation. Other possible complications of bilary atresia include metabolic abnormalities, cyanosis hepatopulmonary syndrome and malignant change in a fibrotic liver.
Liver transplantation is considered for patients who fail to established isfactory bile drainage after portoenterostomy, and for those who uncontrollable, later, complications of cirrhosis. However, it is gradually agreed that portoenterostomy should remain as the first line of treatment.
It is not possible to predict the outcome of the portoenterostomy position at the time of surgery. There has been a gradual improvement results since the operation was first introduced and Kasai’s department. Japan have reported a success rate improving from 13% during the 18 years, to 44% during the next 7 years, followed by an overall stay rate of 50% in the next 6 years. There are nowsignificant numbers of patients who have lived for 10 years after portoemtomy. From the results in our own unit concluded that portoenterostomy is an effective long-term procedure for the atresia in 4050% of cases, but that the remainder will require transportation, mostly within the first 2 years of life.