Von Willebrand disease, type 2M

This code identifies a specific inherited bleeding disorder characterized by qualitative defects in von Willebrand factor (VWF) function, where VWF-dependent platelet adhesion is reduced, but the large VWF multimers are present. Type 2M von Willebrand disease (VWD) involves impaired VWF interaction with platelets or collagen, leading to prolonged bleeding times and increased bruising.

Apply this code when documentation explicitly states a diagnosis of von Willebrand disease, type 2M, often following specialized laboratory testing confirming the specific VWF functional defect. This diagnosis is typically made by a hematologist based on VWF activity assays (e.g., VWF:RCo or VWF:GPIbM) showing disproportionately low activity compared to VWF antigen levels, with normal multimer distribution.

• Ensure the physician documentation clearly specifies "type 2M" VWD, as other VWD types have distinct codes.
• Do not use this code for other qualitative VWD types (e.g., 2A, 2B, 2N) or quantitative deficiencies (type 1, type 3).
• Consider sequencing this code as the primary diagnosis if it is the reason for the encounter, or as a secondary diagnosis if it is a co-morbidity impacting care.