Familial chylomicronemia syndrome (FCS) is a very rare hereditary condition in which individuals lack properly functioning lipoprotein lipase (LPL), an enzyme that clears triglycerides from plasma. The disruption of the enzyme activity leads to very high concentrations of triglycerides and particularly chylomicrons in the plasma (chylomicronemia). Chylomicrons are lipoproteins that transport triglycerides from the gastrointestinal (GI) tract to other parts of the body.1,2
FCS is also referred to as familial LPL deficiency (LPLD), or hyperlipoproteinemia Type 1. In affected patients, the high concentration of chylomicrons in the plasma can lead to a host of problems including acute recurrent inflammation of the pancreas (pancreatitis), development of skin lesions known as eruptive xanthoma, a creamy appearance of the retinal blood vessels (lipaemia retinalis), abdominal pain, and/or abnormal enlargement of the liver and/or spleen (hepatosplenomegaly).1,2
This very rare disease may go undetected, or may be improperly diagnosed as hypertriglyceridemia during childhood. In many cases, it is not until patients are young adults — with severe abdominal pain due to pancreatitis — that they are properly diagnosed and receive specialist medical care. The pancreatitis that often leads to the proper diagnosis can be very serious, requiring hospitalization and, in some cases, can be fatal.1,2
There is no clear diagnostic profile for FCS. A diagnosis of FCS in current clinical practice is mainly based on clinical findings, time of onset, family history and lipid profile by ultracentrifugation. Relevant historical information will likely include a family history of lipid disorders and/or a personal history of abdominal pain or pancreatitis. Moreover, fasting lactescent plasma (i.e., creamy looking blood sample) typically is the trigger to further work up and ultimate diagnosis.1-5
FCS is not well understood. There is currently no pharmacotherapy approved in the United States to treat patients with FCS. More natural history studies are needed to better understand how the disease progresses and how it impacts people’s lives. Additionally, more clinical trials are needed to develop treatment options.