Low-Dose Rituximab Therapy for Antibody-Mediated Rejection in a Highly Sensitized Heart-Transplant Recipient

Antibody-mediated rejection is the B-cell–mediated production of immunoglobulin G antibody against the transplanted heart. The currently available therapies for antibody-mediated rejection have had marginal success, and chronic manifestations of rejection can result in an increased risk of graft vasculopathy and perhaps require repeat transplantation. Rituximab, a monoclonal antibody directed against the CD20 receptor of B-lymphocytes and approved as therapy for lymphoma, can be used in heart-transplant patients for the management of antibody-mediated rejection.We present the case of a 52-year-old woman with high allosensitization (pre-transplantation panel reactive antibody level, 72%) who underwent successful orthotopic heart transplantation. Postoperatively, her acute antibody-mediated rejection with concomitant cellular rejection was successfully treated with low-dose rituximab. The patient died 5 months later because of multiple other medical problems. The present case suggests a role for low-dose rituximab as therapy for antibody-mediated rejection in heart-transplant patients.Key words: Antibodies, monoclonal/therapeutic use; antigens, CD20/immunology; B-lymphocytes/immunology; graft rejection/drug therapy; heart transplantation/pathology; HLA antigens/immunology; immunity, humoral/physiology/therapy; immunoglobulins, intravenous/metabolism; plasmapheresis; rituximab; time factorsAntibody-mediated rejection (AMR) in heart-transplant recipients is mediated by donor-specific antibodies and is histologically defined by linear deposits of immunoglobulin (Ig) and complement in the myocardial capillaries.¹ Antibody-mediated rejection is often accompanied by hemodynamic compromise and is associated with diminished graft survival. Standard immunosuppressive therapy, designed to target T-cell immune function, is largely ineffective against this B-cell–driven process. Various therapies for AMR, although available, can be of marginal use secondary to patients'' comorbidities.^2,3 We present the case of a woman with a history of ventricular assist device (VAD) implantation, dialysis dependence, and severe thrombocytopenia who responded well to the addition of anti-CD20 monoclonal antibody therapy with rituximab after heart transplantation.