Two-step screening strategy for biliary atresia in newborns shows promise

Last Updated: 2020-03-24

By Reuters Staff

NEW YORK (Reuters Health) - Newborn screening for biliary atresia using direct or conjugated bilirubin measurements has a high diagnostic yield, detecting all known infants with the rare liver disorder in a large cross-sectional study of infants born at 14 Texas hospitals.

Timely diagnosis of biliary atresia is a "critical challenge in pediatric hepatology. Treating biliary atresia in newborns earlier can delay or prevent the need for liver transplant; however, treatment typically occurs later because biliary atresia is difficult to detect during its early stages," the authors note in JAMA.

Dr. Sanjiv Harpavat of Texas Children's Hospital in Houston and colleagues assessed the diagnostic yield of a two-stage screening approach for biliary atresia using direct or conjugated bilirubin measurements.

In the first stage, all newborns were tested within the first 60 hours of life. A positive screen was defined as bilirubin levels exceeding derived 95th percentile reference intervals. Infants who screened positive in stage one were retested at or before the two-week well-child visit, with a positive screen defined as bilirubin levels greater than that seen in stage one or greater than 1 mg/dL.

The study included more than 124,000 newborns and the two-stage screening approach identified all seven known infants with biliary atresia, with a sensitivity of 100.0% and a specificity of 99.9%, although the 95% confidence interval around the sensitivity was wide (56% to 100%), "and the study design did not ensure complete ascertainment of false-negative results," the authors note.

The researchers also did a "pre-post" study of 43 infants who underwent the Kasai portoenterostomy for biliary atresia; 24 were treated before screening implementation and 19 infants were treated after screening implementation. They found that infants who underwent the Kasai portoenterostomy were significantly younger after than before screening was implemented (mean age, 36 days vs. 56 days).

"These findings may help inform decision-making about newborn screening for biliary atresia, although further research is needed from larger populations to obtain more precise estimates of diagnostic yield and to better understand clinical outcomes and cost-effectiveness of this screening approach," the researchers conclude.

In a JAMA editorial, Dr. Richard Schreiber notes that biliary atresia "satisfies standard criteria for newborn screening, including a clear case definition, the need for early recognition, acceptable treatment regimens that improve outcome, and health care cost savings. What is lacking is a suitable screening test."

Dr. Schreiber, with BC Children's Hospital, Vancouver, British Columbia, says this study represents "an encouraging step toward the realization of a newborn biliary atresia screening strategy using direct or conjugated bilirubin measurements. Screening for other newborn conditions has often begun with reports similar to this one."

"A national universal biliary atresia screening program with this testing approach would require a well-organized and meticulous infrastructure for implementation and execution. Many lines of research are still required before the program could be advocated to public health stakeholders (clinicians, epidemiologists, economists, government and nonprofit agencies) and policy-makers. In the meantime, biliary atresia remains a disease in need of early recognition," he concludes.

Funding for the study was provided by the National Institute of Diabetes and Digestive and Kidney Diseases. The authors indicated no relevant conflicts of interest.

SOURCE: https://bit.ly/2Jdf4HO and https://bit.ly/39hPNqr JAMA, online March 24, 2020.