Age at Kasai, spleen issues key to biliary atresia outcomes
Surgery after 60 days, spleen problems predict worse results
Babies who had standard Kasai surgery when they were more than 60 days old or had spleen malformations were more likely to have poor outcomes from biliary atresia, a study found.
These factors were better than blood markers of liver damage measured before surgery at predicting long-term liver survival.
“Age at surgery and BASM [biliary atresia splenic malformation] are stronger determinants of the long-term outcome compared to liver biochemistry,” the researchers wrote.
The study, “Multicenter Study on Early Predictors of Biliary Atresia Outcomes,” was published in the Journal of Pediatric Surgery.
Biliary atresia is a congenital disorder where the bile ducts, a series of tubes that carry the digestive fluid bile from the liver to the small intestine, are blocked or absent. As a result, bile builds to toxic levels in the liver, causing liver damage, and leaks into the bloodstream. This can cause biliary atresia symptoms such as dark urine, pale stools, and jaundice (yellowing of the skin and whites of the eyes).
Predicting survival, jaundice clearance odds
The standard first-line treatment for biliary atresia is an operation called the Kasai portoenterostomy. The surgery aims to restore bile flow by creating an alternate route into the small intestine that bypasses the blocked ducts.
This procedure is typically done in infancy and can help minimize liver damage. It has been reported to help more than half of children achieve jaundice clearance within six months, reflected by normalization of blood bilirubin levels. Bilirubin is an orange-yellow pigment of bile that accumulates in biliary atresia patients’ blood and is thought to underlie jaundice.
However, many patients undergoing the Kasai procedure eventually need liver transplants.
An international team of scientists set out to identify factors that could predict the odds of jaundice clearance and of being alive without needing a liver transplant at the latest follow-up (native liver survival).
They retrospectively analyzed outcomes from 630 infants with biliary atresia who underwent the Kasai procedure at any of seven centers across Europe. Their median age at surgery was 54 days.
Slightly more than half (58%) achieved clearance of jaundice, and about half (51%) kept their livers two years after the surgery. Liver transplant was performed on about half of the children at a median age of 1 year.
The researchers examined several factors, including age at surgery, the presence of BASM — spleen abnormalities affecting some biliary atresia patients — and a history of infection with cytomegalovirus (CMV), a virus that can infect the liver. BASM was present in 11% of the infants, and CMV infection was confirmed before surgery in an equal proportion of infants.
The scientists also analyzed blood markers of liver damage, including aspartate aminotransferase (AST) and the aspartate aminotransferase-to-platelet ratio index (APRI).
Statistical models accounting for multiple variables simultaneously showed that a history of CMV infection and having cirrhosis (irreversible liver scarring) prior to surgery were significant predictors of failure to achieve jaundice clearance at six months. In contrast, AST and APRI were found to be weak predictors of jaundice clearance.
When the team looked at factors predicting native liver survival, they found that children who did not achieve jaundice clearance at six months were about 15 times more likely to die or need a liver transplant.
These data indicate that outcomes in the first months after surgery may predict likely long-term outcomes, the researchers noted.
The statistical models also showed that children who underwent surgery when they were more than 60 days old were 30% more likely to need a liver transplant or to die, and children with BASM were 90% more likely.
BASM was a significant predictor of poor native liver survival in infants achieving jaundice clearance, increasing the risk of liver transplant or death by about twofold.
In statistical models accounting for multiple variables, blood markers of liver damage showed no strong predictive potential for long-term outcomes.
“Our results demonstrate that [the chance of native liver survival] is significantly affected by age at [surgery] and BASM whereas CMV infection and cirrhosis are the most important determinants of [clearance of jaundice],” the team wrote.
About the Author
