Hemophilia is an inherited bleeding disorder caused by low levels of clotting factor VIII (hemophilia A) or factor IX (hemophilia B), and it mostly affects males because the genes are on the X chromosome. Patients bleed longer than normal, often into joints and muscles, and severe disease can bleed with no injury at all.
Key symptoms
- Painful, swollen, warm joints from bleeding, often knees, elbows and ankles
- Large bruises and deep muscle bleeds after minor bumps
- Prolonged bleeding after cuts, dental work, surgery or circumcision
- Nosebleeds, gum bleeding or blood in the urine
- Bleeding history in male relatives on the mother's side
What you find on exam
- Swollen, tender joint with reduced range of motion
- Bruises and hematomas; check muscle compartments for tense swelling
- Signs of chronic joint damage: deformity, muscle wasting, limited movement
- Vital signs and pallor for blood loss
- Neurologic check after any head injury
Tests
- Prolonged aPTT with normal PT and normal platelet count
- Mixing study corrects the aPTT, which points to a factor deficiency
- Factor VIII and factor IX activity levels to confirm the type and severity
- Inhibitor testing (Bethesda assay) if factor stops working; imaging for suspected internal bleeding
Treatment basics
- Give factor replacement right away for any significant bleed, before imaging
- Recombinant or plasma-derived factor VIII or IX, dosed by weight and severity
- Prophylaxis to prevent bleeds, including emicizumab for hemophilia A
- Desmopressin or tranexamic acid for mild hemophilia A and mouth or nose bleeds
- Avoid aspirin, NSAIDs and intramuscular injections; physical therapy for joints
Red flags
- Head injury, sudden headache, vomiting or confusion: possible brain bleed
- Bleeding in the neck or throat with trouble breathing or swallowing
- Tense, very painful limb or groin pain with numbness from a deep muscle bleed
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.