Neonatal cholestasis is a rare liver condition affecting newborns, characterized by impaired bile flow from the liver, leading to a buildup of bilirubin and other substances.
What is Neonatal Cholestasis?
The liver produces bile, a digestive fluid that helps the body absorb fats and fat-soluble vitamins, and also carries waste products like bilirubin to the intestines for elimination. When this normal flow of bile is reduced or blocked, neonatal cholestasis occurs.
When bile flow is impaired, bilirubin, a yellowish waste product from the breakdown of old red blood cells, accumulates in the bloodstream instead of being excreted. This accumulation, known as conjugated hyperbilirubinemia, is a hallmark of cholestasis. The disrupted bile flow also means that fats and fat-soluble vitamins (A, D, E, and K) are not properly absorbed in the intestines, which can lead to nutritional deficiencies and affect growth.
Identifying the Signs
Persistent jaundice, a yellowing of the skin and eyes, is often the first and most common symptom, especially if it continues beyond two weeks of age. Prolonged jaundice warrants further investigation.
Another indicator is dark urine, which occurs because the excess conjugated bilirubin in the bloodstream is filtered by the kidneys and excreted in the urine. Conversely, stools may appear pale, white, or chalky due to the lack of bile pigment reaching the intestines. Poor weight gain or difficulty feeding can also be present, as the impaired bile flow hinders the absorption of necessary nutrients.
Underlying Causes
The causes of neonatal cholestasis are diverse. Biliary atresia is a significant cause, involving a blockage or absence of the bile ducts outside the liver, preventing bile from reaching the intestine.
Genetic disorders can also lead to neonatal cholestasis by disrupting bile formation or flow at a cellular level. Examples include Alagille syndrome, which can cause bile duct paucity, and progressive familial intrahepatic cholestasis (PFIC), inherited disorders affecting bile transport proteins. Metabolic disorders, such as alpha-1 antitrypsin deficiency or galactosemia, interfere with the body’s ability to process certain substances, leading to liver damage and cholestasis.
Severe infections, including TORCH infections (Toxoplasmosis, Other, Rubella, Cytomegalovirus, Herpes simplex virus) or bacterial sepsis, can also impair liver function in newborns, leading to cholestasis. Total Parenteral Nutrition (TPN)-associated cholestasis can occur in infants receiving prolonged intravenous feeding.
How Doctors Diagnose
Diagnosis typically begins with a physical examination, where doctors look for characteristic signs. Blood tests are performed to measure bilirubin levels, specifically differentiating between conjugated (direct) and unconjugated (indirect) bilirubin. An elevated conjugated bilirubin level indicates cholestasis and warrants further investigation.
Imaging studies visualize the liver and bile ducts. An abdominal ultrasound can help identify structural abnormalities like gallstones, choledochal cysts, or a small or absent gallbladder, which can suggest biliary atresia. A hepatobiliary iminodiacetic acid (HIDA) scan assesses bile flow by tracking a radioactive tracer from the liver to the intestines. If these initial tests are inconclusive, a liver biopsy, where a small tissue sample is taken for microscopic examination, may be performed.
Treatment Options and Long-Term Care
Treatment for neonatal cholestasis is highly dependent on the underlying cause. For biliary atresia, the Kasai procedure (hepatoportoenterostomy) is a surgical intervention that aims to restore bile flow by connecting the liver directly to the small intestine. This procedure is most successful when performed early, ideally before the infant is 60 days old.
Nutritional support is often needed due to fat malabsorption. Infants may require specialized formulas containing medium-chain triglycerides (MCTs), which are more easily absorbed, and high doses of vitamin supplements. Medications such as ursodeoxycholic acid (UDCA) may be prescribed to improve bile flow and reduce the accumulation of toxic bile acids.
Ongoing medical supervision and regular check-ups monitor the infant’s liver function, nutritional status, and overall growth. Managing potential complications like chronic itching or liver scarring (cirrhosis) is also crucial. In severe cases where liver damage progresses despite other treatments, liver transplantation may be considered as a life-saving option.