A 28-year-old woman with von Willebrand disease is listed for laparoscopic cholecystectomy. Her subtype is type 2B. Preoperative planning should AVOID desmopressin because it can cause:
- A Severe hypertension from sodium retention
- B Worsening thrombocytopaenia from release of abnormal vWF-bound platelets ✓
- C Anaphylaxis due to IgA antibodies
- D Rebound hyperfibrinolysis
Correct answer: B. Worsening thrombocytopaenia from release of abnormal vWF-bound platelets
Explanation
Desmopressin releases stored von Willebrand factor from endothelial cells and works well in type 1 disease. In type 2B, the abnormal vWF has enhanced binding to platelet GPIb, and DDAVP releases this mutant protein into plasma, causing spontaneous platelet aggregation and worsening thrombocytopaenia. Such patients need purified von Willebrand factor concentrate instead. Hyponatraemia, not hypertension, is the classic fluid side effect of DDAVP, and IgA anaphylaxis relates to plasma products.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.