Transfusion-related immune modulation (TRIM)

When to suspect this adverse reaction

Transfusion-related immune modulation (TRIM) is a transient immunosuppression in recipients observed after transfusion of allogeneic blood.

No specific signs or symptoms have been attributed to TRIM and the incidence rate is not known.

Usual causes

There have been no specific mechanisms identified as the pathway for post-transfusion immunosuppression. 
It’s partially due to transfused white cells releasing cytokines, which leads to immune modulation.

There have been a number of reported TRIM-associated effects on the transfusion recipient ranging from improved clinical outcome in renal allograft transplantation to an increased rate of tumour recurrence in cancer surgery patients and an increased rate of post-operative bacterial infection.


No specific investigation process has been defined.

What to do

The most important approach is to avoid allogeneic blood transfusion in general.
Removal of donor white cells by pre-storage filtration of cellular blood components may help to lessen TRIM.