PCD is a metabolic condition that inhibits your body's ability to convert energy from stored fat. For most people, their bodies naturally produce a chemical called carnitine, which allows for fatty acid oxidation to occur. That means they can generate energy regularly and without intervention. For those with PCD, your body doesn't secrete carnitine the way it's supposed to, leaving you unable to convert that energy the normal way, which, if left unaddressed, can lead to cardiac and liver complications. However, with proper supplementation of oral levocarnitine, this condition can lead to a fairly standard life.
Did I do something to cause my PCD?
No, there is nothing you could have done to prevent this, nor is it something you can "catch." You've actually had PCD your entire life because it is strictly a genetic condition. PCD is rare because it's considered an autosomal recessive condition, meaning you can only get it if you inherit two copies of a specific rare gene, or if an even rarer spontaneous mutation occurs during your mom's pregnancy.
What's actually happening in my body?
Carnitine's job is to act like a shuttle, carrying fatty acids into your mitochondria (the part of the cell that produces energy), especially during fasting or illness, when your body leans on fat for fuel. That transport is handled by a protein called OCTN2, which is encoded by a gene called SLC22A5. In PCD, mutations in that gene mean OCTN2 doesn't work properly, so carnitine can't be pulled into your cells efficiently, and it leaks out through your kidneys instead of being reabsorbed. That's why supplementation works: taken in high enough amounts, carnitine can get into your cells through a different route that bypasses the broken pathway.
Can I ever get rid of my PCD?
No, PCD is a condition you will manage for the rest of your life. However, once you build a routine and put the proper safeguards in place for rare emergencies, you will likely be able to do nearly everything you could prior to your diagnosis.
PCD is rare. Researchers estimate it affects roughly 1 in 50,000 people, which can make it feel isolating. But the condition is well understood medically, well studied, and very manageable. Plenty of people with PCD play sports, go to college, have careers, and live full lives without it being a daily source of stress once they've got their routine down.
This page is for general education and is not a substitute for what your own doctor tells you about your specific case.
Last updated October 2026.
Sources
According to PubMed, this page draws on the following peer-reviewed sources:
- Magoulas PL, El-Hattab AW. "Systemic primary carnitine deficiency: an overview of clinical manifestations, diagnosis, and management." Orphanet Journal of Rare Diseases, 2012. https://doi.org/10.1186/1750-1172-7-68
- Longo N, Frigeni M, Pasquali M. "Carnitine transport and fatty acid oxidation." Biochimica et Biophysica Acta, 2016. https://doi.org/10.1016/j.bbamcr.2016.01.023