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R E Michler

Publications and source records attributed to R E Michler.

164 records · Page 10Linked to original sources

Pediatric retransplantation.

Previous studies have attempted to outline the efficacy of heart retransplantation in adults. A limited number of these retransplantation procedures have been performed in children; however, no study to date has evaluated the risk of heart retransplantation in this specific patient population. We conducted a retrospective review of 17 pediatric (non-neonatal) heart transplant recipients who subsequently underwent heart retransplantation. Thirteen male and four female patients underwent retransplantation at four different institutions between 1974 and 1992. Patient age at the time of primary transplantation ranged from 2 to 19 years (mean, 12.5 years) and from 3 to 30 years (mean, 16 years) at retransplantation. The time interval between transplantation procedures ranged from 2 days to 15.6 years and was not predictive of patient outcome. Follow-up after retransplantation ranged from 1 day to 11 years (mean, 2.8 years). All patients were New York Heart Association class 3 or class 4 at the time of retransplantation. After retransplantation all survivors were New York Heart Association class 1. No patient had mechanical device implantation or extracorporeal membrane oxygenation bridge-to-transplantation at primary transplantation or retransplantation. The indication for retransplantation was transplant coronary artery disease (TxCAD) in seven patients (41.2%), acute rejection in four (23.5%), chronic rejection in one (5.8%), chronic rejection associated with TxCAD in four (23.5%), and intraoperative donor organ failure in one (5.8%). No significant difference occurred in linearized rates of rejection or infection or in actuarial freedom from rejection or infection when secondary grafts were compared with primary grafts in patients undergoing retransplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Additive value of immunologic monitoring to histologic grading of heart allograft biopsy specimens: implications for therapy.

BACKGROUND: Currently the sole method available for diagnosis of heart allograft rejection is endomyocardial biopsy. Although this procedure offers important criteria for treatment, it cannot always discriminate between mild episodes of rejection which might be self-limiting and forms which may progress. In an effort to monitor rejection, we have implemented a cellular monitoring strategy aimed at identifying episodes of rejection in biopsy specimens which may evolve into higher grades of rejection. The lymphocyte growth assay is based on the capacity of interleukin-2 receptor-positive T cells to expand in the presence of interleukin-2 and antigen provided by the biopsy fragment. In this study we investigated whether a positive lymphocyte growth assay correlated with and was predictive of subsequent histologic allograft rejection and the development of anti-human leukocyte antigen antibodies. METHODS: Lymphocyte growth assay was performed on 437 biopsy specimens from 76 patients. Patients with mild allograft rejection defined as grade 2 rejection were randomized to treatment according to the results of the lymphocyte growth assay. Anti-human leukocyte antigen antibodies was also measured monthly. Cells grown from the biopsy specimens were tested against the donor cells and allopeptides derived from the donor human leukocyte antigen-DR. RESULTS: A highly significant correlation was observed between the histologic grade of rejection and growth of graft infiltrating cells (p < 0.0001). Lymphocyte growth occurred in 10% of grade 0 versus 60% of grade 3A biopsy specimens. Only 4% of histologically negative cases with negative lymphocyte growth assay progressed to rejection in the next month. In the randomized study in which treatment was based on the lymphocyte growth assay results, progressive rejection occurred in three of four cases with positive lymphocyte growth assay versus only 1 of 11 with a negative lymphocyte growth assay (p < 0.001). A highly significant correlation was found between a positive lymphocyte growth assay and subsequent development of antihuman leukocyte antigen antibodies (p < 0.0006). This finding indicates that cellular rejection evidenced by lymphocyte growth assay ultimately results in humoral antihuman leukocyte antigen antibody mediated rejection. Limiting dilution analysis showed that although the direct recognition pathway prevails in early rejection, cells participating in the indirect pathway also proliferate vigorously in the graft during rejection. CONCLUSIONS: Monitoring of rejection with lymphocyte growth assay is a simple method which provides prognostic information on the outcome of cardiac allografts. Lymphocyte growth assay correlates with histologic rejection and is predictive of future histologic rejection episodes. Lymphocyte growth assay also predicts subsequent development of antihuman leukocyte antigen antibodies and thus may provide a useful method for ascertaining the onset of chronic rejection.

Adult↗