Recurrent Facial Erythema with Cytotoxic T Cell Infiltration as a Possible Reactive Eruption in a Human T-Cell Lymphotropic Virus Type 1 Carrier

Human T-cell lymphotropic virus type 1 (HTLV-1) induces adult T cell leukemia/lymphoma (ATLL), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and carrier. Approximately half of ATLL patients have direct skin involvement of neoplastic cells. However, there exist HTLV-1-associated reactive eruptions with a predominant infiltrate of non-neoplastic CD8+ T cells in ATLL, HAM/TSP and carrier. A 50-year-old Japanese female HTLV-1 carrier had several episodes of itchy, indurated erythema that occurred diffusely on the face and neck, lasted for 2 weeks and spontaneously subsided without sequelae. Histopathologically, CD3+ T cells infiltrated the upper dermis, and part of the infiltrating cells were CD4+CD25+, sharing the phenotype with ATLL neoplastic cells. An aggregate of CD8+ T cells bearing the cytotoxic molecule TIA-1 was also present. It is possible that skin-affinitive HTLV-1+CD4+ T cells propagated and subsequently disappeared as a result of cytotoxic T cell attack.