Blood marker may predict biliary atresia liver transplant need: Study
APRI score distinguished adults needing transplant from those who didn’t
A non-invasive liver function score called the aspartate aminotransferase to platelet ratio index (APRI) may help accurately predict whether adult biliary atresia (BA) patients will need liver transplants, a study showed.
Using an APRI cut-off value of 1.8, the team of researchers in Japan was able to discriminate between patients who ended up needing a liver transplant and those who didn’t with an accuracy of 91.4%.
Other liver function markers evaluated in the study showed lower predictive ability.
“Identifying prognostic markers at 18 years of age that can predict poor outcomes […] during adulthood is crucial for optimal patient management and follow-up,” the researchers wrote.
The study, “Factors predicting the need for liver transplantation in biliary atresia patients after 18 years of age,” was published in Pediatric Surgery International.
Biliary atresia procedure delays transplant need
The most common indication for liver transplant in pediatric biliary atresia patients is when the ducts that  transport the digestive fluid bile from the liver to the small intestine are blocked or absent. This leads to bile accumulation within the liver that results in progressive tissue scarring, or fibrosis, that damages the organ.
The first-line treatment is the Kasai procedure, a surgery that creates an alternate route of bile into the small intestine to restore bile flow. It allows children with BA to delay or eliminate the need for a liver transplant well into adulthood.
“Patients who are spared from transplantation may live for many years with their native [natural] livers despite the progression of cirrhosis [irreversible liver scarring] and chronic liver disease,” the researchers wrote.
These patients are at risk for liver-related complications that can increase the chance of needing a liver transplant in the future. These include cholangitis, or bile duct inflammation, and portal hypertension, or high blood pressure in a major liver vein that is linked to serious complications.
A liver biopsy can evaluate the severity of fibrosis and cirrhosis and help decide if a transplant is needed. But biopsy is an invasive procedure that carries organ injury and bleeding risks, and infants need to be sedated.
Non-invasive biomarkers like APRI, albumin-bilirubin (ALBI), and biliary atresia liver fibrosis (BALF) scores have been shown to predict liver problems. APRI is a ratio between levels of the liver enzyme aspartate aminotransferase and the number of platelets, which are involved in blood clotting.
ALBI is a formula based on blood levels of bilirubin, a marker of liver damage, and albumin, a protein produced by the liver whose lower levels indicate liver problems. BALF is based on blood levels of bilirubin, albumin, and another liver enzyme, as well as age. In all three biomarkers, higher levels are linked to worse liver outcomes.
Whether these non-invasive biomarkers can predict liver transplant need in adult BA patients remains unknown. Identifying such predictors is particularly important because as BA patients grow into adulthood, their more obvious liver donors — their parents — can “surpass the age threshold for liver donation,” the team wrote.
Cholangitis, portal hypertension
With this in mind, researchers in Japan retrospectively examined clinical records of 48 adult BA patients who were followed at their clinic between January 1990 and September 2023. All had their native livers at age 18, and 14 of them (29.2%) had undergone liver transplants at a median age of 24.5.
The most common indications for liver transplant were repeated cholangitis and portal hypertension (28.6% each), and in all but three cases, transplants came from living donors.
The researchers looked for potential predictors at age 18 of future need of a liver transplant.
They found that patients who remained with their native livers had significantly higher albumin levels and platelet counts compared with the transplant group. Native liver survivors also had significantly lower blood levels of several markers of liver damage, including bilirubin, bile acids (a component of bile), and certain liver enzymes.
APRI, ALBI, and BALF scores were significantly lower in the native-liver group relative to the transplant group at age 18. Further statistical analyses showed that the APRI score showed the best potential for predicting the need for liver transplant later in life.
A cut-off value of 1.8 was able to discriminate between patients continuing to live with their native livers and those who subsequently needed liver transplants in 91.4% of the cases.
The rates of native liver survival were significantly higher for patients with APRI scores below 1.8 than for those with higher values after 20 years (96.7% vs. 88.9%), 25 years (96.7% vs. 50%), and 30 years (96.7% vs. 33.3%).
The APRI score may be a way of predicting the need for liver transplant in adult BA patients, the researchers wrote. Larger studies involving multiple centers could validate the study’s findings and establish standardized times and approaches for predicting liver transplant need in BA patients using APRI scores, they said.
About the Author
