Clinical and Hematological Aspects of Haemophilia: A Comprehensive Review for Diagnostic and Therapeutic Monitoring

Haemophilia, a rare X-linked recessive bleeding disorder caused by deficiencies in clotting Factors VIII or IX, presents a significant challenge in diagnostic hematology and lifelong therapeutic management. This comprehensive thesis provides a detailed analysis of the clinical and hematological aspects of haemophilia, with a specific focus on the pivotal role of the medical laboratory technologist. The review systematically elucidates the molecular pathophysiology and correlates the spectrum of clinical features, from spontaneous hemarthroses to chronic arthropathy, with underlying laboratory parameters. It details the complete diagnostic workflow, from initial screening with activated Partial Thromboplastin Time (aPTT) to definitive diagnosis and classification via quantitative factor assays. A major focus is placed on the laboratory's critical role in monitoring both standard and novel therapies, including the management of the primary complication—factor inhibitor development—through the Bethesda assay, and the essential use of chromogenic substrate assays to navigate interferences from non-factor therapies, such as emicizumab. The thesis further explores the laboratory's contribution to prevention strategies, including genetic counseling and pharmacokinetic-guided prophylaxis. In conclusion, while therapeutic advances such as extended half-life concentrates and gene therapy are transforming patient outcomes, the laboratory remains the cornerstone of precise diagnosis, personalized management, and future innovation in haemophilia care, ensuring optimal safety and efficacy for patients.