Interleukin (IL) -8 is a neutrophil chemoattractant cytokine with proinflammatory and growth-promoting activities, which is involved in the pathogenesis of several inflammatory diseases. It is found in high amounts in lesional biopsies of pustular diseases such as psoriasis and palmoplantar pustulosis. We report a 50-year-old woman with a 10-year history of erythroderma with disseminated pustulosis. Skin biopsies showed an epidermotropic infiltrate composed of atypical CD4+ CD8+ lymphocytes with numerous admixed neutrophils. Peripheral blood flow cytometric analysis revealed a major clonal subset of CD3+ CD4+ CD8+ T-cell receptor Vbeta22+ atypical lymphocytes. Bone marrow biopsy, lymph node biopsy and computed thoracoabdominal tomography were normal. Serologies for human T-cell lymphotropic virus type I and human immunodeficiency virus were negative. Our patient's status deteriorated despite topical (nitrogen mustard, psoralen plus ultraviolet A) and systemic (interferon, methotrexate, multiagent chemotherapy) treatments, and she finally died. We showed that our patient's peripheral blood lymphocytes (PBL) spontaneously produced high amounts of IL-8. In contrast, PBL of patients with classical Sézary syndrome produced lower amounts of IL-8. The production of IL-8 by tumour T cells could explain this unusual clinical and histopathological presentation of cutaneous T-cell lymphoma as disseminated pustulosis.