Monoclonal Antibody Prophylaxi

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Medscape Medical News

July 25, 2005 (Los Angeles) — Although surgeons at the University of California, Los Angeles (UCLA), Liver and Pancreas Transplantation Department perform a larger number of combined liver-kidney transplants (CLKT) on severly ill patients since the advent of the Model End-Stage Liver Disease (MELD) organ allocation process, the one-year patient survival rate improved from 73% to 86%, according to a presentation given here by Richard M. Ruiz, MD, at the 11th Annual Congress of the International Liver Transplantation Society.

Since the MELD system of organ allocation replaced the criteria promulgated by the United Network for Organ Sharing (UNOS), significantly more CLKTs are performed in the U.S. The goal of this study was to retrospectively review the factors affecting the outcomes of CLKT patients allocated organs based on MELD criteria vs those allocated organs based on UNOS criteria in the UCLA patient series. Because these recipients are more severely ill than recipients under the UNOS criteria, investigators hypothesized that fewer grafts would survive and that patient mortality rates would increase.

The MELD-allocation group consisted of the 28 patients who underwent CLKT between March 2002 to August 2004. The UNOS-allocation group consisted of all 70 patients who had undergone CLKT between October 1988 and March 2002. According to Dr. Ruiz, the UCLA CLKT patient series is the largest in the world.

The median follow-up for this series of patients was 16 months. MELD-allocated patients were more severely ill than UNOS-allocated patients based on several measures. Median MELD score was 34 in MELD-allocated patients and 24 in UNOS-allocated patients. Nine MELD-era patients had previous liver transplantations compared with seven under the UNOS criteria. Median hospital and intensive care unit stay were 50 and 18 days, respectively, for MELD-allocated patients compared with 34 and 8 days, respectively, for UNOS-allocated patients. Surgery lasted about an hour longer for MELD patients than for UNOS-allocated patients, but liver cold ischemia time was nearly two hours shorter but required a larger volume of transfused blood.

Of the 23 MELD-allocated patients (82.1%) who underwent monoclonal antibody (MAb) induction therapy with either basiliximab or daclizumab, only two patients (8%) experienced rejection episodes. A subgroup of eight hepatitis C virus (HCV)-positive patients also received MAb induction. No HCV-positive patients experienced rejection episodes of liver or kidney; only one of these eight patients experienced biopsy-proven recurrence of HCV within six months posttransplantation.

CLKT is performed more often today, likely because of calcineurin-sparing immunosuppression, improved medical management, and lower cold ischemia times. In addition, MAb induction therapy reduces liver acute rejection rates in patients undergoing CLKT, including those with HCV who appear to improve clinically without an increase in HCV recurrence. These data reveal that transplant surgeons should consider performing CLKT in appropriate patients rather than focusing on the most serious condition first and hoping that the patient stabilizes enough to be a good risk for a second operation.

This study was sponsored by UCLA. Dr. Ruiz was a Fellow at the department of Pancreatic and Liver Transplantation during the time the study was conducted and has no commercial interests to disclose.

11th Annual Congress ILTS: Abstract 88. Presented July 22, 2005.

Reviewed by Gary D. Vogin, MD