What investigations are essential in assessing hemophilia?

In assessing hemophilia, the essential investigations focus on understanding the bleeding tendencies associated with the disorder. The activated partial thromboplastin time (APTT) is pivotal because hemophilia predominantly affects the intrinsic pathway of coagulation, where factor VIII and factor IX play critical roles. Therefore, measuring APTT is crucial, as an extended APTT indicates a potential deficiency in these factors.

Furthermore, the assay for factor VIII and IX levels is essential to confirm the specific type of hemophilia—hemophilia A involves a deficiency in factor VIII, while hemophilia B involves a deficiency in factor IX. By assessing these factors, clinicians can not only diagnose hemophilia but also determine its severity and guide appropriate management strategies.

Other options offered, such as a Complete Blood Count (CBC) and Prothrombin Time (PT), do not provide the specific information required for diagnosing hemophilia, as they do not evaluate the intrinsic pathway directly affected by the disease. Similarly, serum electrolytes and BUN are unrelated to coagulation factors and their assays. Imaging studies like CT scans and MRIs do not contribute to the diagnosis of hemophilia; these are typically reserved for assessing complications related to bleeding. Thus, the focus on