Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.

Diseases

Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Protein C deficiency

*

* Not a rare disease

Other Names for this Disease

  • Hereditary thrombophilia due to protein C deficiency
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Overview

What is protein C deficiency?

What causes protein C deficiency?

How is protein C deficiency inherited?

How is protein C deficiency diagnosed?

How might protein C deficiency be treated?

What is protein C deficiency?

Protein C deficiency is a disorder of blood clotting. People with this condition have an increased risk of developing abnormal blood clots. Protein C is found in the bloodstream and blocks the activity of (inactivates) certain proteins that promote blood clotting. Those with protein C deficiency do not have enough functional protein C to inactivate clotting proteins, which results in an increased risk of developing abnormal blood clots. Other factors can raise the risk of abnormal blood clots in people with mild protein C deficiency. These factors include increasing age, surgery, immobility, or pregnancy. The combination of protein C deficiency and other inherited disorders of blood clotting can also influence the risk. However, most people with mild protein C deficiency never develop abnormal blood clots. Protein C deficiency can be inherited or acquired. Inherited forms are caused by mutations in the PROC gene and inherited in an autosomal dominant fashion.[1]
Last updated: 9/20/2011

What causes protein C deficiency?

Protein C deficiency can be either inherited or acquired. Acquired protein C deficiency may be caused by large blood clots, liver disease, disseminated intravascular coagulation (DIC), infection (sepsis), and vitamin K deficiency. Treatment with warfarin or certain types of chemotherapy can also cause acquired protein C deficiency.[2]

Hereditary protein C deficiency is caused by mutations in the gene that provides instructions for making protein C, called the PROC gene. These mutations disrupt the protein's ability to control blood clotting. If protein C cannot control blood clotting, abnormal blood clots may form.[1]
Last updated: 9/20/2011

How is protein C deficiency inherited?

Hereditary protein C deficiency is inherited in an autosomal dominant pattern, which means one altered copy of the PROC gene in each cell is sufficient to cause mild protein C deficiency. The altered copy of the PROC gene can be inherited from either parent. Individuals who inherit two altered copies of this gene have severe protein C deficiency.[1]
Last updated: 9/20/2011

How is protein C deficiency diagnosed?

A diagnosis of protein C deficiency might be suspected in someone with a deep venous thrombosis (DVT) or a pulmonary embolism, especially if it occurs in a relatively young person (less than 50 years old) or has formed in an unusual location, such as the veins leading to the liver or kidney or the blood vessels of the brain.[3]

Laboratory tests are usually be done to look at the function or quantity of protein C in the blood. Functional tests are usually ordered, along with other tests for abnormal blood clotting, to screen for normal activity of protein C. Based on those results, concentrations of protein C may be measured to look for decreased production due to an acquired or inherited condition and to classify the type of deficiency. If the shortage of protein C is due to an inherited genetic change, the quantity of protein C available and the degree of activity can be used to help determine whether a person is heterozygous or homozygous for the mutation. Genetic testing is not necessary to make a diagnosis.[3]
Last updated: 9/20/2011

How might protein C deficiency be treated?

Most people with mild protein C deficiency never develop abnormal blood clots and thus do not require treatment. However, individuals that have experienced a deep venous thrombosis (DVT) or a pulmonary embolism are usually treated with blood-thinning drugs such as heparin or warfarin, which help to prevent another blood clot from developing in the future.[4] Preventative treatment with these blood-thinning drugs may also be considered in those with a family history of blood clotting as well as in high risk situations such as pregnancy in the postpartum state, surgery, and trauma.[2]

A protein C concentrate (Ceprotin®) was approved by the Food and Drug Administration in 2007 for the treatment of protein C deficiency. High doses of intravenous protein C concentrates can help thin the blood and protect from blood clots. It can also be used a preventative treatment against blood clots during surgery, pregnancy delivery, prolonged immobility, or overwhelming infection in the blood stream (sepsis). Currently, no guidelines exist as to which patients should receive protein C concentrate. It is typically given only at times of increased risk for clotting, or when the blood thinner heparin by itself cannot be safely given because it would lead to an increased risk for bleeding. However, in those with severe protein C who have had severe bleeding complications on long-term blood thinner therapy, protein C concentrate has been used on a regular basis.[5]
Last updated: 9/20/2011

References
  1. Protein C deficiency. Genetics Home Reference. October 2009; http://ghr.nlm.nih.gov/condition=proteincdeficiency. Accessed 9/20/2011.
  2. Cuker A, Pollak ES. Protein C Deficiency. eMedicine Journal. August 2011; http://emedicine.medscape.com/article/205470-overview. Accessed 9/20/2011.
  3. Protein C and Protein S. Lab Tests Online. March 2011; http://labtestsonline.org/understanding/analytes/protein-c-and-s/tab/test. Accessed 9/20/2011.
  4. Congenital protein C or S deficiency. MedlinePlus. March 2010; http://www.nlm.nih.gov/medlineplus/ency/article/000559.htm. Accessed 9/20/2011.
  5. Protein C Deficiency. Clot Connect. June 2011; http://clotconnect.wordpress.com/2011/06/15/protein-c-deficiency/. Accessed 9/20/2011.


Other Names for this Disease
  • Hereditary thrombophilia due to protein C deficiency
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.