- What are common signs and symptoms of FCS?
- What tests are done for pancreatitis and how does it affect my triglyceride, amylase and lipase levels?
- What are triglycerides? What is a chylomicron?
- Why is it so hard to diagnose familial chylomicronemia syndrome (FCS)? How is it diagnosed?
- What is the difference between acute, recurrent acute and chronic pancreatitis?
- What range is considered normal for triglycerides? What affects the levels? Can I cheat on my diet if my levels are in check?
- There are lots of food options that claim “healthy” fats. Why can’t I eat healthy fats?
- Does FCS cause cardiac disease?
- Since FCS is genetic and I have received an FCS diagnosis, can other members of my family also have FCS? Should they be tested?
- Is there a genetic test for FCS?
- How can I get a genetic test for FCS?
1. What are common signs and symptoms of FCS?
The first clinical sign of FCS is often a blood draw that appears “milky” because of the high concentration of triglycerides.3 The first symptom a patient may experience is severe abdominal pain. Other signs, symptoms and complications include:
- Frequent abdominal and back pain
- Vomiting or diarrhea
- Numbness in feet or legs
- Lipemia retinalis (milky appearance of retinal veins and arteries)
- Pancreatitis (inflammation of pancreas)
- Hepatosplenomegaly (swelling of liver and spleen)
- Neurological symptoms (depression, memory loss)
- Xanthomas (fatty deposits in the skin)
2. What tests are done for pancreatitis and how does it affect my triglyceride, amylase and lipase levels?
During a pancreatitis attack, triglyceride, amylase and lipoprotein levels are evaluated by blood and/or urine tests. You may also have an MRI, CT or ultrasound done to check for inflammation of the pancreas.
While it is rare, it has been documented that patients experiencing pancreatitis as a complication of familial chylomicronemia syndrome (FCS) have normal levels of amylase and lipase.1 It is thought that because triglyceride levels are so high, they interfere with the accuracy of the test.3 It is critical that you communicate an FCS diagnosis to your healthcare providers during all encounters so the correct diagnosis can be made.
High triglycerides are the third leading cause of pancreatitis, although it is not fully understood how they are related. It may be due to the increased concentration of chylomicrons in the blood. These may trigger inflammation that activates digestive enzymes in the pancreas.3 However, some people with high triglycerides rarely have pancreatitis; others experience it more frequently. Other causes of pancreatitis include gallstones and excessive alcohol consumption.
3. What are triglycerides? What is a chylomicron?
Triglycerides are a type of fat found in the blood that bodies use for energy. Triglycerides are packaged as chylomicrons. The number of chylomicrons in your blood increases after you’ve eaten and then goes back down as part of the normal digestion process. Chylomicrons are large and bulky, and this design enables travel through the bloodstream.3
4. Why is it so hard to diagnose familial chylomicronemia syndrome (FCS)? How is it diagnosed?
FCS is present at birth because it is a genetic condition. However, the age of onset and symptoms vary from patient to patient. This is also the reason it is very difficult to diagnose FCS. Doctors don’t have a quick and simple test that can tell you if you have FCS.They may evaluate absence or low activity of the enzyme lipoprotein lipase through a blood sample.5
Some people have noticeable FCS symptoms when they are young, such as failure to thrive, colic and abdominal pain. For others, it may show up when they become pregnant. Still for others, they may not get symptoms until adulthood. This may be due to environmental and lifestyle factors, such as dietary fat intake, alcohol consumption, tobacco usage and level of activity or exercise.
5. What is the difference between acute, recurrent acute and chronic pancreatitis?
Patients with FCS may be told they have acute, recurrent or chronic pancreatitis. Acute pancreatitis occurs suddenly and may result in complications and hospitalizations. Recurrent pancreatitis is when you have repeated attacks of acute pancreatitis.5 Chronic pancreatitis also causes sudden and severe pain, but the difference is that the patient will have permanent loss of pancreatic function and organ damage.
6. What range is considered normal for triglycerides? What affects the levels? Can I cheat on my diet if my levels are in check?
Normal triglyceride levels are <150 mg/dL (1.7 mmol/l). Patients with FCS may have severely elevated triglyceride levels, up to 10,000 mg/dL (113 mmol/l or more). However people with “normal” triglyceride levels can develop pancreatitis and people with high triglyceride levels may never develop pancreatitis. If you have received an FCS diagnosis, work with your healthcare team to determine the right level for you.
There are many things that can increase triglyceride levels,3,5 including:
- Medical conditions: Hypothyroidism, uncontrolled diabetes and others
- Diet: Food high in fat, even healthy fats such as avocados and certain nuts
- Prescription medicines: Commonly prescribed drugs, such as estrogen, beta-blockers and some medications for mental illness
- Genetics: There are several genetic disorders that cause the body not to be able to digest fats
- Pregnancy: Triglyceride levels may fluctuate in the 3rd trimester of pregnancy
It’s very important to avoid alcohol if you have been diagnosed with FCS. Alcohol has been shown to cause triglyceride levels to increase.5
Because it is difficult to maintain any diet, but especially an extremely low-fat diet, people with FCS can approach the restrictions as a lifestyle change, not a diet. It is important to not dwell on food choices you should not eat, but rather focus on exploring new foods or making a low-fat diet interesting and different. If it’s a lifestyle change, it may be easier to look at taboo food/drink not as something to “indulge” in.
7. There are lots of food options that claim “healthy” fats. Why can’t I eat healthy fats?
The most important and beneficial first step to managing FCS is adhering to a very low-fat lifestyle, which means consuming around 20 grams of fat per day. When you have FCS, the body can’t break down “healthy” or “unhealthy” fats; it’s all the same.
So, what’s safe? Medium Chain Triglyceride oil is a medical food that is easy for the body to digest. While it is derived from coconut and palm oils, the difference is in how it is processed in your body. MCT oil does not increase triglycerides and does not form chylomicrons.
8. Does FCS cause cardiac disease?
High cholesterol with high low-density lipoprotein (bad cholesterol) in particular is a well-known risk factor for heart disease. Even though people with FCS have severely high levels of triglycerides, they do not appear to be at a higher risk for cardiac disease. It is thought that the chylomicrons are too large to enter the arteries.
9. Since FCS is genetic and I have received an FCS diagnosis, can other members of my family also have FCS? Should they be tested?
FCS is an autosomal recessive genetic trait, like red hair or blue eyes. That means it can only occur if you inherit a mutated gene from both parents. If genes inherited from just one parent carry FCS, then you will not show symptoms of FCS.
If both your mother and father are genetic carriers who are not affected by the disease, you have a 25 percent chance of getting the disease. You have a 50 percent chance of being an unaffected genetic carrier and you have a 25 percent of not being affected and not being a carrier.
Siblings of people with FCS have an increased chance to have the condition, or could be a carrier. Therefore, your immediate family, including parents, brothers or sisters, and children, should see a specialist if they have high triglycerides or show other signs and symptoms of FCS.
If you have FCS, there is a chance that any children you have may also have the condition or they will be carriers for the gene. Being a carrier means that they carry a disease-causing variant, but will be unaffected. This resource helps explain different levels of risk for autosomal recessive conditions.
Learn more about genetic diseases and how to discuss genetic diseases with your loved ones.
10. Is there a genetic test for FCS?
Genetic testing can look for pathogenic variants (mutations) in a person’s genes that may cause FCS. A positive test result can confirm a clinical diagnosis by a qualified healthcare provider.
However, a negative test result does not necessarily eleminate FCS. It just means a disease-causing variants was not found in the genes that were examined.
11. How can I get a genetic test for FCS?
FCS Genetic Testing is a no-cost, confidential genetic testing program offered to patients who meet the following criteria:
- Extremely high (severe) triglyceride levels ( more than 750 mg/dL ( or 8.4 mmol/L) ), on two fasting blood test in a row.
- No other known causes of high triglyceride levels.
The FCS Genetic Testing program offers no-cost education on disease and genetic testing. Please call GeneMatters with any questions at +1 888.478.1494
2 http://my.clevelandclinic.org/health/diseases_conditions/hic_Pancreatitis/dd_overview (Accessed 9/23/2016).
3 Chait A, Subramanian S, Brunzell JD. Genetic Disorders of Triglyceride Metabolism. [Updated 2015 Jun 12]. In: De Groot LJ, Chrousos G, Dungan K, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-.
4 Michael Miller, Neil J. Stone, Christie Ballantyne, Vera Bittner, Michael H. Criqui, Henry N. Ginsberg, Anne Carol Goldberg, William James Howard,Marc S. Jacobson, Penny M. Kris-Etherton, Terry A. Lennie, Moshe Levi,Theodore Mazzone and Subramanian Pennathur. “Triglycerides and Cardiovascular Disease.” Circulation. 2011;123:2292-2333, published online before print May 23, 2011.
5 Williams, L.,Rhodes, K. S., Karmally, W., Welstead, L. A., Alexander, L., Sutton, L. (2018). Familial chylomicronemia syndrome: Bringing to life dietary recommendations throughout the life span. Journal of Clinical Lipidology, 12(4), 908-919..