BASD is a treatable but serious liver condition

BASDs are caused by problems with the enzymes that produce bile acids. These issues disrupt normal bile acid production. As a result, bile cannot flow from the liver to the small intestine (cholestasis). Cholestasis often appears as prolonged yellowing of the skin (jaundice) in newborns. It affects about 1 in 2500 babies, with BASD making up around 2% of cholestatic jaundice cases.

BASD is a genetic disorder, which means the disorder is usually passed down through the genes from parents.

In people with BASD, there is a change—or mutation—in the gene responsible for making the enzymes that are required to produce bile acids.

Symptoms of BASD

The most common symptom of BASD is a yellow coloring of the skin or white part of the eyes (jaundice) that lasts more than 2 weeks.

Other signs and symptoms of liver involvement include:

Poor growth (not meeting weight or height milestones for age)

Vitamin deficiencies (vitamins A,D,E, or K)

Pale, foul-smelling stools

Dark (tea-colored) urine

Enlarged liver or spleen

Elevated liver enzymes

Diagnosing BASD

If you or your loved one is exhibiting any of the symptoms mentioned above, it’s important for your or your loved one's doctor to run tests in order to diagnose the cause. They will ask about medical history and complete a physical exam. The doctor may perform blood and urine tests, including:

  • Direct bilirubin
  • Alanine aminotransferase (ALT)/aspartate aminotransferase (AST)
  • Gamma glutamyltransferase (GGT)
  • Primary bile acids

A doctor can diagnose BASD through genetic testing, which identifies mutations in genes that can cause cholestasis—a condition where bile flow is reduced or stopped.

Early diagnosis and treatment of BASD may lead to better outcomes

Early diagnosis and treatment of BASD are important. Without treatment, BASD can cause liver damage, and in some cases, the liver may stop working properly, requiring a transplant. Identifying and treating the condition early may help prevent serious liver problems and may improve outcomes.

Talk to a health care provider to learn more about BASD.