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Factor I deficiency (or congenital fibrinogen deficiency) is a rare bleeding disorder. People with factor I deficiency have problems with a substance in the blood called factor I protein. As a result, they bleed easily after minor trauma or surgery. They can even bleed with no explanation.

There are three different types of factor I deficiency. One type, hypofibrinogenemia, occurs when a patient’s blood level of factor I protein is lower than usual, while patients with afibrinogenemia have no factor I protein at all. People with the third type, dysfibrinogenemia, have normal levels of factor I protein, but the protein doesn’t work. This can lead to bleeding problems, clotting problems, or both. Afibrinogenemia is passed to children by genes from both parents. The other types only require genes from one parent.

Bleeding from the nose, gums, or tongue is common with all three types. Some patients bleed internally, with blood collecting in joints and around muscles. Rarely, bleeding can occur in the brain or other internal organs. Women with congenital afibrinogenemia can bleed more than usual during menstruation. They might need treatment to carry a pregnancy to term.

Afibrinogenemia affects about 150–300 people in the United States. The other two types are even more rare. Patients are usually diagnosed between birth and early childhood.

The only FDA-approved treatment for patients with afibrinogenemia and hypofibrinogenemia is RiaSTAP®, a concentrate of fibrinogen. Patients with dysfibrinogenemia are treated with plasma or cryoprecipitate, since RiaSTAP can cause too much clotting.

Sources: Genetics Home Reference, Food and Drug Administration, HemAware, National Hemophilia Foundation, MedScape.

Reference to a specific product, process, or service does not constitute an endorsement or recommendation by Diplomat Pharmacy Inc., and any such reference is provided for educational purposes only.

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Featured Technology

A mobile health care application for patients with hemophilia and related bleeding disorders. The app helps patients conveniently track their personal infusion records and bleeding event history, as well as share important injury and treatment information with members of their health care team.

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