Eosinophilic Folliculitis of the Scalp Associated with PD-1/PDL1 Inhibitors

The document reported a case of eosinophilic folliculitis of the scalp that occurred during nivolumab therapy, an immune checkpoint inhibitor. This condition initially appeared as lichen planopilaris and was managed with topical steroids and fusidic acid cream, resulting in partial benefit and a scarring outcome without discontinuing nivolumab. The study concluded that immune checkpoint inhibitors could induce an inflammatory response, exposing hair follicle antigens and leading to a loss of immuno-privilege. The authors hypothesized that steroids might shift a primarily lichenoid reaction towards folliculitis.