Cryoglobulinemia in HCV-Positive Renal Transplant and Liver Transplant Patients

Mixed cryoglobulinemia (MC) is a systemic disease that is often associated with hepatitis C virus (HCV) infection. In this chapter, we review the prevalence and consequences of MC in kidney (KTx) and liver (LTx) transplant recipients. The prevalence of cryoglobulinemia is quite high in maintenance KTx patients and is comparable to that observed in hemodialysis patients. In addition, cryoglobulinemia is often but not always associated with HCV infection. However, cryocrit levels tend to be lower in transplant patients than in non-renal-failure patients, which might explain why developing cryoglobulinemia after kidney transplantation rarely results in clinical symptoms, especially cryoglobulinemic syndrome. In LTx recipients, cryoglobulinemia occurs relatively frequently, i.e., in 19.5–30% of patients. In addition, cryoglobulinemia is often but not always associated with HCV infection and is more frequently symptomatic in LTx than in KTx patients, i.e., in 22–44% of LTx patients. When MC occurs after kidney or liver transplantation, dedicated treatment should be contemplated only in those patients who are symptomatic. Treatment is aimed at targeting HCV infection when present. In very rare cases, rituximab therapy may be of value.