From the Guidelines
The primary purpose of irradiating platelets is to prevent transfusion-associated graft-versus-host disease (TA-GVHD) in recipients, particularly those who are immunosuppressed or have weakened immune systems 1.
Key Points
- Irradiation of platelets is recommended for certain conditions, such as transfusions from relatives or for patients with specific medical conditions, to prevent TA-GVHD 1.
- The recommended dose for irradiation is a minimum of 25 Gy 1.
- Irradiation can also help prevent platelet alloimmunization and reduce the risk of febrile nonhemolytic reactions 1.
- Leukoreduction, which involves removing leukocytes from blood products, is also important in preventing TA-GVHD and other complications, and is often used in conjunction with irradiation 1.
Clinical Considerations
- Clinicians should be aware of the irradiation policies of their local blood suppliers and communicate with them about patients who require irradiated products 1.
- The use of irradiated platelets may be particularly important in patients with acute leukemia or other conditions that require immunosuppressive therapy 1.
- In cases where irradiation is not possible, alternative methods such as UV irradiation pathogen inactivation techniques may be considered to prevent TA-GVHD 1.
From the Research
Purpose of Irradiating Platelets
The purpose of irradiating platelets is to prevent transfusion-associated graft-versus-host disease (TA-GvHD) and transfusion-transmitted infections 2. Irradiation of platelet products is generally used to inactivate T cells, which can cause TA-GvHD in immunosuppressed patients.
Methods of Irradiation
There are several methods of irradiation used for platelet products, including:
- Gamma irradiation: This is the most commonly used method, which has been shown to be effective in preventing TA-GvHD 3, 4.
- X-ray irradiation: This method has been shown to be as effective as gamma irradiation in preventing TA-GvHD, with no significant effect on platelet quality and activation markers 5, 6.
- UV-illumination: This method is used to reduce the growth of infectious agents during platelet storage, but it can also induce oxidative conditions and platelet pre-activation, leading to platelet storage lesion (PSL) 2.
Effects of Irradiation on Platelet Quality
The effects of irradiation on platelet quality are:
- Gamma irradiation: Has been shown to have no significant effect on the quality of platelet products, but can induce oxidative effects and lead to PSL 2, 3.
- X-ray irradiation: Has been shown to have no significant effect on platelet quality and activation markers, and can be used as a safe and effective alternative to gamma irradiation 5, 6.
- UV-illumination: Can induce oxidative conditions and platelet pre-activation, leading to PSL, and its use is not yet justified due to its effects on platelet quality 2.
Indications for Irradiation
Irradiation of platelet products is indicated for patients who are at risk of developing TA-GvHD, including: