Herpes Zoster Infection Following Solid Organ Transplantation: Incidence, Risk Factors and Outcomes in the Current Immunosuppressive Era

Herpes zoster (HZ) infection is a frequent and serious complication of organ transplantation that has not been examined in the current era of immunosuppression. All solid organ transplants performed between 1994 and 1999 (n = 869) at our center were analyzed to determine the incidence, complications and risk factors for developing HZ. The overall incidence of HZ was 8.6% (liver 5.7%, renal 7.4%, lung 15.1% and heart 16.8%). The median time of onset was 9.0 months. We observed high rates of cutaneous scarring (18.7%) and post-herpetic neuralgia (42.7%). Independent organ-specific risk factors included: female gender and mycophenolate mofetil therapy (liver), and antiviral treatment other than prolonged cytomegalovirus (CMV) prophylaxis (renal and heart). For all organs combined, induction therapy and antiviral treatment other than prolonged CMV prophylaxis were independent predictors for the development of HZ. Herpes zoster is common and results in significant morbidity for solid organ transplant recipients. Risk factors include induction therapy and antiviral drug therapy other than CMV prophylaxis. The latter variable identifies a subpopulation that is likely at increased risk of latent herpesvirus reactivation. The high first-year post-transplant incidence rate suggests immunization pretransplant, even in varicella zoster virus immunoglobulin seropositive individuals, may be preventative.