Herpes zoster in psoriasis patients undergoing treatment with biological agents: prevalence, impact, and management challenges.

As TNF-α is a major factor in the immune defense against herpes zoster (HZ); an increased incidence and severity of HZ cases were suspected in patients undergoing treatment with TNF antagonists. Several studies and clinical experience provided evidence that the incidence of HZ increases by twofold to threefold in this patient category. The number of severe cases of HZ, with multisegmental, disseminated cutaneous, and/or systemic involvement, is also increased. Concerning psoriasis patients under biologicals, the clinician should be more alert for an eventual HZ event, in particular during the first year of biological treatment, and be aware of the possibility of more severe HZ cases. HZ may also undergo an age-shift toward younger patients. Rapid identification of risk factors for severe HZ, such as severe prodromal pains and/or the presence of satellite lesions, is recommended. The treatment recommendations of HZ in this patient group are identical to the recently published guidelines for the management of HZ. The live attenuated viral vaccine OKA/Merck strain anti-HZ vaccination is recommended before initiating biological treatment in psoriasis patients. The new adjuvanted anti-HZ vaccine will probably also benefit patients while on biological treatment.