Familial Chylomicronaemia Syndrome (FCS)
Familial chylomicronaemia syndrome (FCS) is a rare inherited condition that causes extremely high levels of triglycerides (a type of fat) in the blood.
Overview
Familial chylomicronaemia syndrome (FCS) is a rare inherited condition that causes extremely high levels of triglycerides (a type of fat) in the blood. Because the body cannot properly break down triglycerides, fat particles called chylomicrons build up in the bloodstream. This can lead to recurrent episodes of severe abdominal pain and inflammation of the pancreas (pancreatitis).
Causes and Genetics
FCS is caused by changes (mutations) in genes involved in breaking down triglycerides. Most commonly, it is due to mutations affecting the lipoprotein lipase (LPL) pathway. FCS is inherited in an autosomal recessive pattern, meaning a person must inherit two altered copies of the gene (one from each parent) to develop the condition. Parents who carry one altered copy are usually healthy carriers.
Symptoms and Features
Symptoms often begin in childhood or adolescence but may also appear in adulthood.
Characteristic Symptoms and Features
- Recurrent severe abdominal pain
- Episodes of pancreatitis
- Nausea and vomiting
- Extremely high triglyceride levels on blood tests
Other Associated Symptoms and Features
- Fatigue
- Eruptive xanthomas (small yellowish skin bumps, often on the back or arms)
- Lipaemia retinalis (milky appearance of blood vessels in the eye)
- Enlargement of the liver or spleen
Pancreatitis is the most serious complication and can be life-threatening.
Treatment
Standard triglyceride-lowering medications are not usually effective in FCS. Patients are usually managed through specialist lipid or metabolic centres.
Research and Future Directions
Ongoing research is focused on developing targeted treatments that reduce triglyceride production or enhance their clearance. Gene-based therapies and novel RNA-targeted treatments are being studied. Improved awareness and earlier diagnosis aim to reduce pancreatitis risk and improve quality of life.