Prevalence of monoclonal immunoglobulins after liver transplantation: relationship with posttransplant lymphoproliferative disorders.

摘要

BACKGROUND: A high incidence of serum monoclonal immunoglobulins (mIgs) has been described after solid organ transplantation. For transplant recipients, the prevalence of posttransplant lymphoproliferative disorders (PTLDs) has been reported to be between 2% and 6%. The relationship between the finding of serum mIg in transplant recipients and the subsequent development of PTLDs is not clearly documented. METHODS: We retrospectively analyzed all cases of mIg and PTLD that occurred in 86 liver transplant recipients who survived more than 3 months. Patients were characterized by protein electrophoresis, immunofixation electrophoresis, pre- and post-liver transplantation Epstein-Barr virus (EBV) serology, EBV presence in lymphoproliferative tissues by in situ hybridization, type of infection episodes, rejection episodes, and immunosuppressive treatment. RESULTS: Thirty-eight patients (44%) had abnormal immunofixation electrophoresis with an electrophoretic Ig peak. Twelve patients had a polyclonal Ig peak, and 26 patients had mIgs (30%). These 26 patients were divided into two groups: 13 patients had a transient mIg peak with a mean delay for normalization of electrophoresis of 2 months, and 13 patients had a permanent mIg peak. No correlation could be demonstrated between the appearance of abnormal banding and indications for transplantation, age of patients, and acute rejection rate. There was a strong correlation between occurrence of viral infections and presence of permanent mIg. Three patients with permanent mIg (23%) developed PTLD and died. CONCLUSIONS: We concluded that the prevalence of mIg after liver transplantation was 30%. Viral infections increase the risk of developing mIg. Persistence of mIg beyond 7 months may be regarded as prelymphomas necessitating a careful follow-up in these patients.