Hemophagocytic lymphohistiocytosis caused by herpes simplex virus type 1 in a young adult: a case report with literature review.

Hemophagocytic lymphohistiocytosis is a severe hyperinflammatory syndrome that can be potentially life-threatening without appropriate treatment. Although viral infection is the most common trigger of hemophagocytic lymphohistiocytosis, cases of herpes simplex virus type 1-induced hemophagocytic lymphohistiocytosis are rare in adults. This study aims to provide a comprehensive overview of the clinical characteristics and treatment outcomes associated with HSV-1-induced HLH. We herein report an adult case of hemophagocytic lymphohistiocytosis caused by herpes simplex virus type 1, diagnosed on the basis of peripheral blood metagenomic next-generation sequencing results. The patient exhibited a favorable response to treatment, involving dexamethasone, intravenous immunoglobulin, and acyclovir. Notably, etoposide administration was deemed unnecessary, and there has been no recurrence of the disease within the year following treatment. Early and sensitive recognition, rapid and precise diagnosis, and timely and appropriate treatment facilitated the successful treatment of this case.