Overview
Familial chylomicronemia syndrome (FCS), also called lipoprotein lipase deficiency or type I hyperlipoproteinemia, is a rare inherited condition where the body cannot properly break down fats in the blood. Normally, an enzyme called lipoprotein lipase (LPL) clears fatty particles called chylomicrons from the bloodstream after meals. In FCS, this process is severely impaired, causing triglyceride levels to build up to dangerously high levels — often 10 to 100 times above normal. This fat buildup can cause repeated episodes of severe abdominal pain, inflammation of the pancreas (called pancreatitis), and a range of other symptoms. Pancreatitis attacks can be life-threatening and may happen without warning, often triggered by eating fatty foods, drinking alcohol, or even stress. Over time, repeated attacks can permanently damage the pancreas. Managing FCS centers on an extremely low-fat diet — typically less than 10 to 15 grams of fat per day — which is very restrictive and difficult to maintain. A newer FDA-approved medication called volanesorsen (brand name Waylivra) is available in some countries to help lower triglyceride levels. While FCS is not curable, careful management can reduce the risk of dangerous complications and improve quality of life.
Key symptoms:
Severe stomach pain, often in the upper abdomenRepeated episodes of pancreatitis (inflammation of the pancreas)Nausea and vomitingCreamy or milky appearance of blood (lipemia)Yellowish fatty deposits under the skin called xanthomasEnlarged liver or spleenFatigue and general feeling of being unwellMemory problems or difficulty concentrating (brain fog)Anxiety and depression related to dietary restrictions and unpredictable attacksPale, fatty stoolsLoss of appetite
Clinical phenotype terms (22)— hover any for plain English
Autosomal recessive
Passed on when both parents carry the same gene change; often skips generations
Variable
Can begin at different ages, from infancy through adulthood
FDA & Trial Timeline
2 eventsTryngolza: FDA approved
adjunct to diet to reduce triglycerides in adults with familial chylomicronemia syndrome (FCS)
Ikaria Bioscience Pty Ltd — PHASE1, PHASE2
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
2 availableRedemplo
as an adjunct to diet to reduce triglycerides in adults with familial chylomicronemia syndrome (FCS)
Tryngolza
adjunct to diet to reduce triglycerides in adults with familial chylomicronemia syndrome (FCS)
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Familial chylomicronemia syndrome.
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Caregiver Resources
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Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.What is my exact genetic mutation, and what does it mean for my treatment options?,How low does my fat intake need to be, and can a dietitian help me create a realistic meal plan?,Am I a candidate for volanesorsen or any other newer medications?,What should I do if I think I am having a pancreatitis attack — when should I go to the emergency room?,Should my family members be tested for this condition?,Are there any clinical trials I might be eligible for?,How often do I need blood tests and specialist check-ups to monitor my condition?
Common questions about Familial chylomicronemia syndrome
What is Familial chylomicronemia syndrome?
Familial chylomicronemia syndrome (FCS), also called lipoprotein lipase deficiency or type I hyperlipoproteinemia, is a rare inherited condition where the body cannot properly break down fats in the blood. Normally, an enzyme called lipoprotein lipase (LPL) clears fatty particles called chylomicrons from the bloodstream after meals. In FCS, this process is severely impaired, causing triglyceride levels to build up to dangerously high levels — often 10 to 100 times above normal. This fat buildup can cause repeated episodes of severe abdominal pain, inflammation of the pancreas (called pancreat
How is Familial chylomicronemia syndrome inherited?
Familial chylomicronemia syndrome follows a autosomal recessive inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
Are there clinical trials for Familial chylomicronemia syndrome?
Yes — 1 recruiting clinical trial is currently listed for Familial chylomicronemia syndrome on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Familial chylomicronemia syndrome?
25 specialists and care centers treating Familial chylomicronemia syndrome are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.
What treatment and support options exist for Familial chylomicronemia syndrome?
2 patient support programs are currently tracked on UniteRare for Familial chylomicronemia syndrome. See the treatments and support programs sections for copay assistance, eligibility, and contact details.