Variation in FVIII/FIX activity in haemophilia: classification and clinical implications

Haemophilia is an inherited, x-linked bleeding disorder. Patients with haemophilia lack clotting factor VIII (FVIII) or factor IX (FIX) causing spontaneous or prolonged bleeding. The hallmark of severe haemophilia is recurrent joint bleeding, eventually leading to severe crippling arthropathy. Functional limitations and the need for lifelong treatment have a large impact on a patient’s daily life. Classification of haemophilia Haemophilia is classified into the types and quantity of clotting factor deficiency. Haemophilia A patients lack FVIII and haemophilia B patients lack FIX. In 1958 haemophilia was classified in three severities based on clinical observations; 3 IU/dl had less complications of haemophilia than patients with baseline levels