Fatal Chronic Varicella-Zoster Viral Infection in a Young Man With Chediak-Higashi Syndrome.

Chediak-Higashi syndrome (CHS) is a rare autosomal recessive primary immunodeficiency characterized by partial oculocutaneous albinism, neurologic involvement, and a predisposition to severe infections. Patients are particularly susceptible to developing hemophagocytic lymphohistiocytosis (HLH), which significantly worsens prognosis. We report the case of a 19-year-old male with CHS, under long-term immunosuppressive therapy for chronic HLH, who developed chronic VZV infection. Despite treatment with valacyclovir, the lesions progressed, and virological investigations confirmed the diagnosis of acyclovir-resistant varicella-zoster virus (VZV). The clinical course was marked by the appearance of neurological symptoms and a fatal outcome. To our knowledge, this is the first reported fatal case of chronic VZV infection with systemic dissemination in a patient with CHS. This case highlights the risk of resistance associated with long-term prophylaxis and the complexity of managing herpesvirus infections in immunocompromised patients receiving JAK inhibitors.