Presensitized Pediatric Heart Transplant Recipients
Submitted by Kathleen Hurley,RN, MSN, CPNP and Traci Boschert, RN 

A heart transplant evaluation involves numerous diagnostic studies and procedures as well as an extensive list of blood tests.  An essential part of every heart transplant evaluation is a blood test that measures a patient’s panel reactive antibodies.The results of this test are required prior to listing a patient for a heart transplant.  Panel reactive antibody (PRA) is measured as a percentage reactive to a panel of representative human leukocyte antigens (HLA) in the general population.  The test identifies the presence of pre-formed antibodies that the patient may have to donor HLA types, and reflects a probability of having antibodies directed against a percent of the general population.  Patients with a PRA >20% are considered presensitized and at increased risk for rejection following transplantation.  Many pediatric heart transplant centers will not transplant presensitized patients unless they have a negative prospective donor crossmatch.  This can severely limit the ability to find a suitable donor.  Our institution does not require that a presensitized patient have a negative prospective donor crossmatch.  Instead, we use a heightened immunosuppression protocol aimed at decreasing the risk of rejection in this patient population. 

At the International Society for Heart and Lung Transplantation (ISHLT) 25th Anniversary Meeting, Dr. Holt from St. Louis Children’s Hospital presented data from our heart transplant program on presensitized patients and the immunosuppression protocol employed in this patient population.  A perioperative plasmapheresis, post-transplant plasmapheresis, polyclonal antilymphocyte globulin, and cytoxan immunosuppression protocol was employed in 11 patients with a positive crossmatch to their allografts.  Rejection frequency, severity and time course were reviewed in these patients.  Median follow-up was 3.25 years. 

All patients had at least one rejection episode, and 10 of the eleven first episodes occurred less than 4 weeks after transplant.  Four of the ten rejection episodes were associated with heart failure, and three of these had rebound rejection episodes between 3-6 weeks after the initial rejection episode.  Late onset rejection, or rejection greater than 6 months post-transplant, only occurred in 3 patients, and noncompliance was documented in one of the cases.  Survival for the group at one year was 91% and 79% at 3 years with one death from rejection.  One can infer from our data that rejection in these patients will occur very early after transplant with severe symptomatology, but can be successfully treated without an increased risk for late rejection.  The results of this study continue to direct the way in which we manage these complicated patients.  As our experience continues to grow, we will refine our protocol in order to reduce the risk and severity of initial rejection episodes and avoid rebound episodes. 

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