Herpes zoster (HZ) incidence and severity among patients who received solid organ transplants (SOTs) are most pronounced among those who received heart or lung transplantation, older patients, and in the absence of cytomegalovirus (CMV) prophylaxis, according to a study published in Frontiers in Immunology. Although it was previously known that HZ incidence and HZ-related complications occur more frequently and with higher severity in solid organ transplant recipients, numbers varied extensively between studies.
To conduct the study, the investigators reviewed the records of 1033 transplant recipients following their first heart (HTx), lung (LuTx), liver (LiTx), or kidney (KTx) transplantation between 2000 and 2014. These records were analyzed for varicella zoster virus (VZV) polymerase chain reaction (PCR), clinical indications of HZ, and other complications.
Across all patient records reviewed, 108 study participants (10.5%) were diagnosed with HZ. Of these patients, 36 were HTx recipients, 17 were LuTx recipients, 15 were LiTx recipients, and 40 were KTx recipients. This translated to 17% of HTx recipients, 14% of LuRx recipients, 6% of LiTx recipients, and 9.2% of KTx recipients being diagnosed with HZ.
Significant risk factors, determined via multivariable analysis, included patients being aged 50 years or older, which type of organ transplant was received, reception of CMV prophylaxis, and the type of anti-rejection therapy given. Out of the 108 patients diagnosed with HZ, 33 (31%) experienced complications, including post-herpetic neuralgia, disseminated disease, and cranial nerve involvement.
“In summary, this study shows that incidence of HZ is high after organ transplantation with severe complications,” the authors write in the study. “The incidence of HZ after HTx or LuTx is significantly higher than after LiTx or KTx. Use of CMV prophylaxis significantly decreases HZ incidence. A rational method to prevent HZ after organ transplantation might be to use CMV prophylaxis, and in our opinion booster vaccination in seropositive transplant candidates is advisable.”
According to the investigators, vaccination against HZ has been shown to be effective in preventing VZV infection in otherwise healthy elderly individuals. Although the live attenuated vaccine cannot be given to patients receiving immunosuppressive medication due to the risk of induced infection, the subunit vaccine, which does not contain live virus, can be administered to this population. The authors note that more studies are necessary to confirm the efficacy of this vaccine in transplant recipients.
Kho MML, Roest S, Bovée DM, et al. Herpes zoster in solid organ transplantation: incidence and risk factors. Front Immunol. 2021; 12: 645718. Published online 2021 Mar 18. doi:10.3389/fimmu.2021.645718