Clinical meaning
Heart transplant rejection occurs when the recipient's immune system recognizes donor HLA antigens as foreign. Hyperacute rejection (minutes-hours) involves preformed antibodies. Acute cellular rejection (weeks-months) is T-cell mediated with lymphocytic infiltration of the myocardium. Antibody-mediated rejection involves donor-specific antibodies causing complement activation and endothelial damage.
Diagnosis & workup
Diagnostics & workup: - Order surveillance endomyocardial biopsies per protocol - Order donor-specific antibody (DSA) panel - Order echocardiogram for LV function decline - Order cell-free donor-derived DNA (dd-cfDNA) as non-invasive marker - Order gene expression profiling (AlloMap) - Monitor drug levels of immunosuppressants
Risk factors: - Medication non-adherence (most common cause of late rejection) - Prior rejection episodes - Young recipient age - Female donor to male recipient - HLA mismatch - CMV serostatus mismatch - Inadequate immunosuppression levels