HEMOPHILIA A: HEMATOLOGICAL EVALUATION AND CLINICAL TREATMENT

Abstract

Hemophilia A is a hereditary disease characterized by a deficiency of coagulation factor VIII, which results in spontaneous or traumatic bleeding in joints, muscles and internal organs. The severity of the disease depends on the residual level of factor VIII activity, being classified as mild, moderate or severe. Clinical treatment consists of replacing factor VIII through intravenous infusions, which can be performed prophylactically or on demand. The hematological evaluation of patients with hemophilia A involves measuring factor VIII, carrying out coagulation tests and detecting inhibitors, which are antibodies that neutralize the action of exogenous factor VIII. Objective: to analyze the main aspects of hemophilia A, addressing its etiology, pathophysiology, diagnosis, treatment and complications. Methodology: The methodology used followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) checklist, which consists of a set of recommendations for the preparation and presentation of systematic reviews and meta-analyses. The databases consulted were PubMed, Scielo, Web of Science, using the following descriptors: “hemophilia A”, “factor VIII”, “bleeding”, “treatment”, “inhibitors”. Articles published in the last 10 years were included ( 2013-2023), in Portuguese or English, that addressed the relevant aspects of hemophilia A. Articles that did not fit the proposed theme, that had low methodological quality or that were duplicates were excluded. Results: 17 articles were selected. Hemophilia A is caused by mutations in the F8 gene, located on the X chromosome, which encodes factor VIII. Factor VIII is a glycoprotein that acts as a cofactor for factor IX in the intrinsic coagulation pathway. Factor VIII deficiency prevents the formation of stable clot fibrin, leading to prolonged bleeding. Laboratory tests include the activated partial thromboplastin time (APTT), which is prolonged in hemophilia A, and the dosage of factor VIII, which is decreased in the disease. The level of factor VIII activity determines the disease severity: mild (>5% and <40%), moderate (>1% and <5%) or severe (<1%). Treatment can be carried out prophylactically, with regular doses to prevent bleeding, or on demand, with occasional doses to treat bleeding episodes. The choice of type and frequency of treatment depends on several factors, such as the severity of the disease, the patient's lifestyle, availability of resources and individual preferences. Conclusion: The conclusion of this systematic literature review is that hemophilia A is a complex disease, which requires early diagnosis and adequate treatment, aiming to improve patients' quality of life. Advances in biotechnology have provided new treatment options, such as long-acting recombinant concentrates, bypass agents and gene therapies, which can offer greater safety and efficacy to patients with hemophilia A.