Immunohistological study of skin involvement in Kikuchi's disease.

Five patients with histiocytic necrotizing lymphadenitis (Kikuchi's disease) with erythematous or popular skin lesions were studied. All patients healed naturally within a few months like the patients with no skin involvement. Histological findings for the skin lesions mimicked cutaneous malignant lymphoma. The infiltrated mononuclear cells usually demonstrated positive reactions for Ki-M1p (20-63%), lysozymes (13-54%), MT-1 (18-64%), UCHL-1 (22-39%) and LN2 (17-36%). OPD-4 and L26 positive cells were few in number. These results suggest that the infiltrated cells in a Kikuchi's disease skin lesion are composed of the same components as the affected lesion in the lymph node.