Severe disseminated VZV in an immunocompromised host temporally associated with recent recombinant adjuvanted herpes zoster vaccination

Background: Recombinant adjuvanted herpes zoster vaccine (Shingrix) effectively prevents varicella-zoster virus (VZV) reactivation and is recommended for older and immunocompromised adults. Case presentation: We report a severe early disseminated VZV reactivation occurring 14 days after primary Shingrix vaccination in an 80-year-old man with a history of lymphocytic lymphoma in biological relapse and secondary hypogammaglobulinemia. Initial presentation featured multimetameric necrotic and hemorrhagic thoracic lesions, which progressed despite oral valaciclovir to a diffuse cephalocaudal vesicular eruption with fever and severe pain, prompting hospitalization. Workup identified VZV-associated bone marrow involvement with acute anemia requiring transfusion; PET imaging excluded lymphoma transformation. The patient improved under intravenous acyclovir (10 mg/kg every 8 h) with daily local care, followed by extended valaciclovir prophylaxis. Given the severity and timing, the second Shingrix dose was withheld. Discussion: Causality is difficult to establish: primary varicella could not be fully excluded, and vaccine-induced immunity would not yet be established after a single early dose. Nonetheless, the short latency, immunocompromised status, and concordance with rare reports of early post-vaccination zoster suggest a possible association. This case highlights the importance of reporting to pharmacovigilance systems and differentiating adverse events from vaccine failure, without undermining the overall favorable safety profile of Shingrix in high-risk populations.