Progressive Familial Intrahepatic Cholestasis 3
Synonyms
1
Overview
Progressive familial intrahepatic cholestasis type 3 (PFIC3), a type of progressive familial intrahepatic cholestasis, is a late-onset hereditary disorder in bile formation that is hepatocellular in origin. Onset may occur from infancy to young adulthood. The condition usually leads to end-stage liver disease by the end of the second decade.
Symptoms
Clinical signs of cholestasis (discolored stools, dark urine) appear within the first year of life in about one third of patients, or later with recurrent episodes of jaundice and mild pruritus. PFIC3 evolves into secondary biliary cirrhosis. Gastrointestinal bleeding due to portal hypertension might be the presenting symptom in adolescents or young adults.
Causes
ABCB4 gene mutations (7q21) cause PFIC3. The ABCB4 gene provides instructions for making a protein called multi-drug resistant 3 protein (MDR3), that moves certain fats called phospholipids across cell membranes. Outside liver cells, phospholipids attach (bind) to bile acids. Large amounts of bile acids can be toxic when they are not bound to phospholipids. Mutations in the ABCB4 gene lead to a lack of phospholipids available to bind to bile acids. Low biliary phospholipid levels are insufficient to maintain solubility of cholesterol and promote bile lithogenicity. A buildup of free bile acids damages liver cells and leads to liver disease.
Diagnosis
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)
Treatment
- Ursodeoxycholic acid therapy (UDCA) should be initiated in all patients to prevent liver damage.
- Beneficial effects of UDCA are usually observed in patients who harbored at least one missense mutation.
- In half of the patients, UDCA therapy fails and liver transplantation is required due to liver failure.
- In patients responding to UDCA, PFIC3 may be complicated by cirrhosis, portal hypertension and hepatocellular carcinoma.
- Specialized follow-up is mandatory and lifelong.