Biliary atresia—the most common cause of chronic liver disease in newborns—occurs when bile ducts inside and outside of the liver are blocked, preventing the bile from draining into the intestines. Instead, the bile remains in the liver, where it builds up and causes damage. Early diagnosis is critical because a newborn’s outcome often depends upon how rapidly the liver is damaged in the first few weeks of life.
“There are only two treatments for biliary atresia. The first is a Kasai portoenterostomy, a surgical procedure that connects the bile drainage directly to the intestinal tract. If successful, it can allow a child to grow and remain in fairly good health for several years,” says Yumirle Turmelle, MD, a pediatric hepatologist at St. Louis Children’s Hospital who serves as medical director of the liver transplant program. “The amount of damage an infant’s liver sustains prior to the Kasai procedure affects how well the surgery works and how long it is effective, and in turn how soon a patient may need to undergo a liver transplant, the only other treatment for the disease.”
Statistics show that of patients with biliary atresia who undergo the Kasai procedure, about one-third of them will never need a liver transplant because there was minimal liver damage and the Kasai procedure provided good bile drainage. Another third of patients will benefit from the Kasai for a time—sometimes into their teens—but will eventually need a transplant. The final third of patients will experience little benefit from the procedure and will need a transplant during their first year of life.
An experienced Liver Care Center
The Liver Care Center at St. Louis Children’s Hospital (SLCH) and Washington University School of Medicine is one of the country’s leading centers in the care of children with all forms of liver disease. On average, Liver Care Center surgeons perform 15-20 liver transplants annually, half of those for infants with biliary atresia. The youngest infant receiving a transplant at SLCH was 9 days old; the smallest babies have weighed about 4 kilograms.
“One of the reasons our pediatric liver transplant program is among the top 10 in the country is that we successfully perform these surgeries on tiny babies and not just older children and teenagers,” says Jeffrey Lowell, MD, FACS, surgical director of SLCH’s kidney and liver transplant program. “Despite the fact that we are doing these high-risk transplants, we maintain an extremely high survival rate compared to the national average, with 97 percent of all patients surviving three years post-transplant since 2000.”
The Liver Care Center also maintains one of the shortest wait times for liver transplant patients—averaging three to four months—compared to the national average, which exceeds one year.
“The size of our liver transplant program has enabled us to develop our expertise in using all forms of organ donations—a whole liver from a newborn; a split transplant, with three-fourths of an adult liver transplanted into an adult patient and one-fourth into a baby; segmenting or reducing a liver to fit the transplant patient; and using living donor livers,” says Dr. Lowell. “Our short wait times draw patients from around the country requesting second opinions. In these cases, we recommend that parents double-list their children so that they receive a transplant as soon as possible, whether here at Children’s or in their hometown.”
Once patients are transplanted, the focus shifts from the complications of biliary atresia to maintaining the viability of the transplanted organ. “Although these patients will be on immunosuppressant medication the rest of their lives, the good news is that the babies we transplant need just a very low dose,” says Dr. Lowell. “This probably is due to their being so young that their immune systems haven’t completely matured, coupled with the fact that of all organs transplanted, the liver is the most tolerant of the procedure, and patients are most tolerant of it.”
Diagnosing biliary atresia
Biliary atresia sometimes is not diagnosed immediately because its symptoms are similar to jaundice that results from breastfeeding. “One easy method of helping to determine the diagnosis is examining a baby’s stool,” says Michelle Nadler, RN, PNP-BC, an SLCH transplant nurse practitioner. “Babies with biliary atresia have extremely light-colored stools because bile isn’t being released from the liver into the intestines. In addition to the stool color and jaundice, other symptoms are dark urine, a distended abdomen and poor weight gain.”
Physicians may also test for elevated levels of conjugated bilirubin, which can indicate a problem with bile secretions that may be related to an obstruction or liver disease. Once an infant is referred to the Liver Care Center, blood tests measuring liver enzymes, bilirubin, albumin and total protein, clotting studies (e.g., prothrombin time and partial thromboplastin time), viral studies and blood culture are performed. Imaging tests include an abdominal ultrasound and hepatobiliary scan. A liver biopsy can help establish the diagnosis, but the definitive diagnosis is made by an intraoperative cholangiogram, a contrast study performed by the surgeons in an attempt to visualize an open connection between the bile duct system and the intestines.
“Studies have concluded that if a specialized liver program such as ours at the Liver Care Center receives a child with an early diagnosis of biliary atresia, institutes treatment and a surgical procedure—proceeding seamlessly to transplantation if necessary—patients have a much better chance of long-term survival,” says Dr. Lowell. “Our success with these patients certainly backs those findings.”