Von Willebrand disease, type 2N

This code represents Von Willebrand disease (VWD) type 2N, a rare inherited bleeding disorder characterized by a qualitative defect in the von Willebrand factor (VWF) protein. Specifically, type 2N VWD involves a defect in the VWF's ability to bind to factor VIII (FVIII), leading to accelerated clearance of FVIII and a secondary FVIII deficiency, mimicking mild hemophilia A. Patients typically present with mucocutaneous bleeding symptoms.

Use this code when documentation explicitly states a diagnosis of Von Willebrand disease, type 2N, confirmed through laboratory testing. This includes scenarios where VWF antigen levels are normal, but VWF:FVIII binding assays are abnormal, and FVIII levels are disproportionately low compared to VWF activity. It is appropriate for initial diagnoses, follow-up care, and management of bleeding episodes related to this specific VWD subtype.

• Differentiate from other VWD types (e.g., 2A, 2B, 2M) which have distinct VWF functional defects.
• Ensure laboratory results, such as VWF:FVIII binding assay and FVIII levels, support the diagnosis of type 2N.
• Do not code secondary FVIII deficiency (D66) separately, as it is an inherent feature of type 2N VWD.