What reflex test should be done on a patient with an abnormal APTT who is suspected of having hemophilia?

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Quizplus · Accepted Answer

An abnormal APTT is suggestive of a clotting factor deficiency, hence a factor assay is necessary to confirm the diagnosis of hemophilia. Platelet function assay would not be helpful as platelets are not directly affected in hemophilia. Quantitative fibrinogen assay and assay for D-dimer would also not aid in the diagnosis of hemophilia.

What Reflex Test Should Be Done on a Patient with an Abnormal