A Case of Subcutaneous Panniculitis-Like T-cell Lymphoma With Hemophagocytic Lymphohistiocytosis in an HIV Patient.

Subcutaneous panniculitis-like T-cell lymphoma (SPTL) is a rare subtype of non-Hodgkin lymphoma that manifests as panniculitis-like skin lesions. It frequently co-occurs with hemophagocytic lymphohistocytosis, a life-threatening hyperinflammatory syndrome. The majority of SPTL cases express αβ T-cell receptors (SPTL-AB) and have a favorable prognosis with oral immunosuppressive agents. We report a 37-year-old male patient with HIV infection who had a history of low-grade fever for one year, multiple tender subcutaneous nodules on both thighs, and cytopenia. He received several courses of antibiotics without significant improvement. A random skin biopsy showed lobular panniculitis and he was treated with steroids, but his fever recurred after steroid withdrawal. A second skin biopsy confirmed the diagnosis of SPTL. A bone marrow examination revealed hemophagocytic lymphohistiocytosis. He was successfully treated with cyclosporin A and prednisolone and achieved a complete response after one year of drug discontinuation. Panniculitis-like skin lesions have various etiologies and may present as a clinical mimic of lupus erythematosus panniculitis. The selection of an optimal site for skin biopsy is crucial to avoid erroneous diagnoses and adverse outcomes. We report a case of SPTL in an HIV-positive patient, which illustrates this diagnostic challenge.