Certification Exam Qbank

Hemophilia B is a congenital deficiency of coagulation factor IX. It occurs less frequently than hemophilia A and is an X-linked recessive condition affecting male patients in greater numbers. Factor IX, activated by factor VIII, subsequently activates factor X, which helps with the conversion of fibrinogen to fibrin. Factor IX deficiency interferes with the clotting cascade, which can lead to spontaneous hemorrhage or hemorrhage associated with trauma. Signs and symptoms of factor IX deficiency include easy bruising, hematuria, epistaxis, and hemarthrosis. Diagnosis is determined through analysis of bleeding scores and through coagulation screening testing and coagulation factor assays. Reproducible low factor IX activity levels, with exclusion of other possible causes, is consistent with hemophilia B. It can be considered mild, moderate, or severe based on the degree of bleeding. Treatment for all cases consists of bolus intravenous dosing of factor IX product followed by dosing every 8 hours until hemostasis is obtained. Plasma-derived factor IX concentrates use fractionation to separate screened donor plasma. Recombinant factor IX has been genetically engineered and is equally proven safe and effective with the treatment of hemophilia B. Treatment for major bleeding should aim to keep factor activity level at 50–80%. Adjunctive aminocaproic acid may be necessary for high-risk procedures.

Desmopressin (A) is used in the treatment of minor and major cases of bleeding in mild hemophilia A, minor and major bleeding cases of type 1 von Willebrand disease, and minor bleeding cases in type 2 von Willebrand disease. Factor VIII product (C) is used in the treatment of minor and major cases of moderate to severe hemophilia A. Fresh frozen plasma (D) is indicated in the treatment of minor and major bleeding in factor XI deficiency.