Herpes zoster granulomatous dermatitis in metastatic lung cancer treated with nivolumab: A case report.

Granulomatous dermatitis (GD) is the most common among a variety of skin reactions that may occur in the varicella-zoster virus (VZV) reactivation area. It is thought that the formation of granulomas may be the result of a delayed hypersensitivity reaction to viral envelope glycoproteins. Immune checkpoint inhibitors (ICIs), such as nivolumab stimulate T cells and promote hypersensitivity reactions, leading to the formation of granulomas in VZV wrapping proteins, thus triggering VZV-GD. Few cases of the use of ICIs in patients diagnosed with VZV-GD have been reported in the literature. Here, we report the clinical case of a patient with metastatic lung cancer which was treated with nivolumab who subsequently developed VZV-GD. Accurate clinical diagnosis and prompt treatment with antiviral agents have resulted in a complete resolution of the clinical picture. KEY POINTS: Significant findings Treatment with ICIs may result in VZV reactivation. Accurate differential diagnosis and early treatment led to the resolution of VZV-GD. WHAT THIS STUDY ADDS: Few cases of ICI and VZV reactivation have been reported in the literature. Full and timely resolution of VZV-GD allowed the continuation of ICI treatment.