Varicella zoster virus meningitis under ustekinumab because of plaque psoriasis

Ustekinumab, a monoclonal antibody that binds to the shared p40 subunit of interleukin ( IL )‐12 and IL ‐23, is approved in the USA and Europe for moderate to severe plaque psoriasis. There are concerns that biologic treatments like ustekinumab may lead to an increased rate of infections. We report a 77‐year‐old woman who developed varicella zoster virus meningitis 8 weeks after initiation of ustekinumab therapy because of plaque psoriasis. She presented clinically with sudden onset of fatigue, vertigo, nausea and epileptic seizures. Investigations of the cerebrospinal fluid revealed 522/3 cells, lactate 2.9 mmol/L, protein 232 mg/dL and 2.4 × 10 3 varicella zoster virus. After 3 weeks of therapy with acyclovir she recovered. We conclude that infection by varicella zoster virus has to be considered as a differential diagnosis in patients with newly developing neurological or psychiatric abnormalities under immunosuppressive therapy.