Hemophilia Symptoms, Risk Factors, Types, and Treatment

Hemophilia is a rare bleeding disorder in which blood doesn’t clot normally. A person with hemophilia is missing clotting factor proteins needed to clot the blood, which leads to spontaneous bleeding or bruising. The disorder is usually inherited, but it can also be acquired.

There are several different types of hemophilia, each differs by the specific clotting factor that is affected. The two most common types are hemophilia A and hemophilia B.

This article discusses the hemophilia, its causes, types, and common symptoms. It also discusses what you can expect during diagnosis and treatment.

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Hemophila Types and Symptoms

There are two common types of hemophilia: type A (factor 8 deficiency or “classic” hemophilia) and type B (factor 9 deficiency, once widely called “Christmas disease” after the first person with the disorder described in the medical literature). Depending on the severity and type of a patient’s hemophilia, bleeding may occur spontaneously (without injury) or after surgery or trauma.

According to the Centers for Disease Control and Prevention symptoms of both types of hemophilia include:

  • Bleeding into the joints, which can cause swelling and pain or tightness in the joints, especially the knees, elbows, and ankles
  • Bleeding into the skin (bruising) or muscle and soft tissue (hematoma)
  • Bleeding of the mouth and gums that is hard to stop after tooth loss
  • Bleeding after circumcision
  • Bleeding after injections
  • Bleeding in the head of an infant after a difficult delivery
  • Blood in the urine or stool
  • Frequent, hard-to-stop nosebleeds

Who Is at Risk?

Men born into families with a history of hemophilia are at risk. To understand the inheritance of hemophilia, we need to talk a little about genetics. Typically, biological males inherit an X chromosome from their mother and a Y chromosome from their father, while biological females inherit an X chromosome from each parent.

The Hemophilia Federation of America reports a family history in 70% of hemophilia cases, with inherited genes passed from parent to child. A mother who carries the gene has a 50% chance of passing it on to a baby. If she passes the gene to a daughter, the daughter will be a carrier. If she passes the gene to a son, he will have hemophilia. Because the father passes along the Y chromosome to his children, a son cannot inherit hemophilia from his father.

Diagnosis

Hemophilia is suspected when a person has excessive bleeding and is diagnosed by measuring the coagulation factors, which are proteins needed to clot the blood to stop bleeding.

Your physician will likely start with laboratory tests to assess the entire coagulation system. These are called the prothrombin time (PT) and partial thromboplastin time (PTT).

The PT test, which measures the clotting ability of clotting factors 1, 2, 5, 7, and 10, is usually normal in people with hemophilia A or B.

The PTT test measures the clotting ability of factors 8, 9, 11, and 12. Unless there is a clear family history, usually all four factors are tested at the same time. In the case of hepatitis A or B, clotting takes longer than usual, and there will be reduced activity of factor 8 (in hemophilia A) or factor 8 (in hemophilia B).

These tests give your physician the percent of the activity of each factor, which is low in hemophilia. Diagnosis can be confirmed by genetic testing.

Types 

Hemophilia can be classified by the particular coagulation factor missing:

  • Hemophilia A results from a deficiency in factor 8.
  • Hemophilia B results from a deficiency in factor 9.
  • Hemophilia C (also called Rosenthal syndrome) results from a deficiency in factor 11.

Hemophilia can also be classified by the amount of coagulation factor found. The less coagulation factor you have, the more likely you are to bleed:

  • Mild: 6–40%
  • Moderate: 1–5%
  • Severe: < 1%

Treatment

Hemophilia is often treated with clotting factor concentrates. These factor concentrates are infused via a vein (IV). Hemophilia can be treated in two different methods: on demand only (when bleeding episodes occur) or prophylaxis (receiving factor once, twice, or three times per week to prevent bleeding episodes).

How you are treated is determined by multiple factors, including the severity of your hemophilia. In general, people with mild hemophilia are more likely to be treated on demand as they have significantly less bleeding. Fortunately, the majority of hemophilia treatments are administered at home. Parents can learn how to administer the factor to their children through a vein at home or a home health nurse can administer the factor. Children with hemophilia can also learn how to administer factor concentrates to themselves, often before becoming teenagers.

Although factor concentrates are the preferred treatment, this treatment is not available in all countries. Hemophilia can also be treated with blood products. Factor 8 deficiency can be treated with cryoprecipitate (a concentrated form of plasma). Fresh frozen plasma can be used to treat factor 8 and factor 9 deficiency.

In mildly affected patients, a medication called desmopressin acetate (DDAVP) can be administered via a vein or nasal spray. It stimulates the body to release stores of factor 8 to assist in the cessation of bleeding.

In 2022, the Food and Drug Administration (FDA) approved Hemgenix (etranacogene dezaparvovec) for the treatment of some adults with hemophilia B. Hemgenix is the first gene therapy for hemophilia B and is a one-time treatment that is given by IV.

In 2023, the FDA approved Roctavian (valoctocogene roxaparvovec-rvox), the first gene therapy for adults with severe hemophilia A. Like Hemgenix, it is a one-time treatment that is given by IV.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Organization for Rare Disorders. Hemophilia B.

  2. National Library of Medicine: MedlinePlus. Hemophilia.

  3. Centers for Disease Control and Prevention. What is hemophilia?.

  4. Hemophilia Federation of America. Hemophilia A.

  5. Centers for Disease Control and Prevention. Diagnosis of hemophilia.

  6. Wheeler AP, Gailani D. Why factor XI deficiency is a clinical concern. Expert Rev Hematol. 2016;9(7):629-637. doi:10.1080/17474086.2016.1191944

  7. Centers for Disease Control and Prevention. Treatment of hemophilia.

  8. National Library of Medicine: DailyMed. Hemgenix—etranacogene dezaparvovec kit [drug label].

  9. Food and Drug Administration. FDA approves first gene therapy for adults with severe hemophilia A.

By Amber Yates, MD
Amber Yates, MD, is a board-certified pediatric hematologist and a practicing physician at Baylor College of Medicine.