Case for diagnosis
We describe a 73-year-old male patient who was previously healthy. Two months prior to presenting to our department, the patient noticed a dermatosis involving the trunk, upper and lower limbs, consisting of multiple pruriginous patches, infiltrated plaques, and nodules with an erythematous surface. The patient did not complain of any additional constitutional symptoms besides pruritus. There were no complaints of weight loss, anorexia or malaise.\nPhysical examination revealed a dermatosis involving, in a bilateral and symmetrical fashion, the upper torso, abdomen, and proximal upper and lower limbs. The dermatosis consisted of roughly annular patches and plaques, with unequal infiltration, exhibiting an erythematous surface. The lesions were painless on palpation (). The examination of lymph node chains was unremarkable. Palpation of the abdomen revealed no mass or organomegaly.\nIncisional cutaneous biopsy revealed the presence of diffuse infiltration by intermediate-sized lymphoid cells, with immunohistochemical expression of CD45, CD4, CD56, and CD123 and negativity for myeloperoxidase, CD3, CD2, CD5, and CD7 ( and ).\nAxial tomography of the thoraco-abdominal and pelvic regions, blood count, myelogram, bone biopsy, and immunophenotyping of peripheral and medullary blood did not reveal evidence of systemic involvement at the time.\nThe patient was started on oral prednisolone therapy (40 mg/day), which led to partial remission of the cutaneous lesions and pruritus. However, relapse was observed after the first month of therapy. After six months of follow-up, the patient still showed an exclusively cutaneous involvement, but rapid and fatal progression of the disease occurred after 8 months of follow-up, resulting in the patient's death.