Patient 'wallet card' text for HPA-1a antibodies

The Medical Director of a transfusion service in Southern California writes that a patient has requested a wallet card for her HPA-1a antibodies. He asks if there is a standard format, and whether the following proposed text would be satisfactory:

"Based on genetic testing, Jane Doe, DOB 00/00/00, tests negative for Human Platelet Antigen 1a (HPA-1a). She has developed antibodies to HPA-1a which dramatically reduce her response to platelet transfusions and have caused neonatal alloimmune thrombocytopenia during a prior pregnancy. She is also at risk for post-transfusion purpura if she receives HPA-1a positive platelets. Please discuss this issue with the blood bank prior to transfusing platelets to this patient."

Editors' Note: the following e-Network Forum dicussions may be germane to this topic:

• Informing patients when pre-transfusion testing shows that their blood contains red cell antibodies
• The use of medical alert bracelets for patients with clinically significant antibodies

The following comments have been received.

ADDENDA September 24, 2007

1. The Medical Director of a large University Hospital in Southern California agrees that a wallet card is a good idea and proposes the following revised text:

"Based on genetic testing, Jane Doe, DOB 00/00/00, tests negative for Human Platelet Antigen 1a (HPA-1a). She has developed antibodies to HPA-1a which dramatically reduce her response to platelet transfusions and have caused neonatal alloimmune thrombocytopenia during a prior pregnancy. She is also at risk for post-transfusion purpura if she receives HPA-1a positive platelets. If Jane requires transfusion, she should preferably receive HPA-1a negative platelets and washed red cells. Please discuss this issue with the blood bank prior to transfusing platelets to this patient."

ADDENDA October 1, 2007

2. The Medical Director of a large blood supplier in California suggests the following revision to the above text:

Based on genetic testing, Jane Doe, DOB 00/00/00, tests negative for Human Platelet Antigen 1a (HPA-1a). She has developed antibodies to HPA-1a which dramatically reduce her response to platelet transfusions and have caused neonatal alloimmune thrombocytopenia during a prior pregnancy. She is also at risk for post-transfusion purpura if she receives HPA-1a positive platelets is transfused with HPA-1a positive blood components of any kind. If Jane requires transfusion, she should preferably receive HPA-1a negative platelets and washed red cells. Please discuss this issue with the blood bank prior to transfusing any blood components to this patient.

Please submit comments to the e-Network Forum.

Ira A. Shulman, MD
CBBS e-Network Forum Editor & Moderator

W. Tait Stevens, MD
CBBS e-Network Forum Assistant Editor & Moderator