Adult renal transplant recipients are at elevated risk for developing post-transplant herpes zoster, according to researchers at the Mayo Clinic in Rochester, Minn.
They studied the incidence and risk factors for post-transplant varicella zoster virus (VZV) infection among 612 adult kidney transplant patients. Herpes zoster developed in 37 patients, which corresponded to a follow-up time-adjusted incidence of 11.2% at four years post-transplant, the investigators reported in Transplant Infectious Disease (2008; published online ahead of print).
The incidence rate of zoster was relatively constant between six months and four years, yielding an average incidence of about 28 cases per 1,000 person-years. In contrast, the incidence of zoster in the United States is estimated at 3.2 cases per 1,000 person-years, the researchers pointed out.
The risk of developing post-transplant zoster increased with increasing age at transplant. Each decade increment in age conferred a 42% increase in risk of developing zoster. VZV seronegativity at the time of transplant was associated with a 3.4-fold greater risk of zoster compared with seropositivity.