The changing pattern of humoral rejection in cardiac transplant recipients

Background. Most humoral rejection (HR) episodes occur early after cardiac transplantation and are associated with hemodynamic compromise and poor prognosis. Late cases of HR (> 6 months after transplant) have been reported. We examined the differences in clinical characteristics and outcomes in patients presenting with HR in the early (< 6 months) and late transplant periods. Methods. A retrospective chart review was performed of all cases of HR at a single large transplant center from January 1, 1995 to March 1, 2006. Results. A total of 37 adult transplants had biopsy-proven HR; 13 patients had early HR and 24 patients had HR a mean of 5 yr after transplantation (range, 7 months to 17 yrs). Treatment for HR included plasmapheresis, cyclophosphamide, and rituximab. The age of the early and late humoral rejecters was similar (58 +/- 14 vs. 50 +/- 14 yrs; P=0.12). There was a trend toward more women in the early HR group (54% vs. 33%). Use of left ventricular assist devices was similar (38% vs. 33%). Early rejecters were more likely to have positive cross-matches (46% vs. 8%; P < 0.01). Patients with late HR had a coexistent diagnosis of malignancy, or significant recent infection in 50% vs. 8% for early HR, suggesting an activation of a nonhuman leukocyte antigen antibody-mediated immune response to an acute illness. One-year survival after the diagnosis of HR was 78% for the both groups (P=NS). Conclusions. Humoral rejection occurs now more frequently in patients with remote transplants and is commonly associated with the presence of malignancy or infection.