Haemophilia A - Diagnosis

Diagnosis

The diagnosis may be suspected as coagulation testing reveals an increased PTT in the context of a normal PT and bleeding time. PTT test are the first blood test done when haemophilia is indicated. However, the diagnosis is made in the presence of very low (<10 IU) levels of Factor VIII.

A family history is frequently present, although not essential. Recently, genetic testing has been made available to determine an individual's risk of attaining or passing on hemophilia

Diagnosis of hemophilia A also includes a severity level which can range from mild to severe based on the amount of active and functioning factor VIII detected in the blood. Factor VIII levels do not typically change throughout an individual's life. Severe haemophilia A is the most common form occurring in 60% of patients. Severe haemophilia A is indicated by active Factor VIII levels less than 1 or 2% Severe haemophiliacs have frequent serious bleeds (20+ times per year), these bleeds often occur spontaneously without trauma or injury. Moderate haemophilia is indicated by active Factor VIII levels between 1–5% and a lower, but variable frequency of bleeding episodes, particularly of spontaneous bleeds. Mild haemophilia is indicated by active Factor VIII levels between 5–25%. Patients with mild haemophilia often experience few or no bleeding episodes except in the case of serious trauma (i.e. compound fracture of a bone), tooth extraction, or surgery.