Progressive familial intrahepatic cholestasis type 2 (PFIC2), a type of progressive familial intrahepatic cholestasis, is a severe, neonatal, hereditary disorder in bile formation that is hepatocellular in origin and not associated with extrahepatic features. A rare inherited condition where bile is unable to drain from the liver where it builds up and causes progressive liver damage. The condition has an early onset and usually leads to end-stage liver disease by the end of the second decade. The various types of this condition differ in the origin of the genetic defect (liver-specific ATP-binding cassette transporter on chromosome 2q24). Type 2 is also associated with an increased risk of liver cancer in the first few years of life.
The signs and symptoms of PFIC2 are typically related to liver disease only; however, these signs and symptoms tend to be more severe than those experienced by people with PFIC1:
- Liver fibrosis
- Liver cirrhosis
- End-stage liver disease
- severe pruritus
- Loose stool
- Foul-smelling discolored stool
- dark urine
Mutations in the ABCB11 gene (2q24) are responsible for PFIC2. The ABCB11 gene provides instructions for making a protein called the bile salt export pump (BSEP). This protein is found in the liver, and its main role is to move bile salts (a component of bile) out of liver cells. Mutations in the ABCB11 gene result in the buildup of bile salts in liver cells, damaging these cells and causing liver disease. BSEP is only expressed in hepatocytes, and extrahepatic features are not present in PFIC2.
Home medical testing related to Cholestasis, progressive familial intrahepatic 2, are:
- Home Cholesterol Tests
- Home Triglycerides Tests
- Home Blood Pressure Tests
- Home Blood Pressure Monitors
- Home Heart Tests
- Heart Rate Monitors
- Irregular Heartbeat Detection
- Heart Electrocardiogram (ECG)
Close monitoring of hepatocellular carcinoma should be offered from the first year of life. Due to hepatocellular carcinoma and rapid liver failure, the course in patients with PFIC2 appears to be more severe than in patients with PFIC1.
Initial treatment is supportive, with the use of agents to treat cholestasis and pruritus, including the following:
- Ursodeoxycholic acid therapy (UDCA) should be initiated in all patients to prevent liver damage but is not fully effective.
- Rifampin is helpful to control pruritus.
- Nasobiliary drainage may help to select potential responders to biliary diversion.
- However, because of severe cholestasis, liver failure or hepatocellular carcinoma, half of patients are ultimately candidates for liver transplantation (LT).
Specialized follow-up is mandatory and lifelong.