Kikuchi's disease.

Histiocytic necrotizing lymphadenitis or Kikuchi-Fujimoto disease (KFD) was described in 1972. Painful, palpable lymphadenitis is localized to one or two sites in the head and neck territories in young adults (third decade) a nd is associated with fever. Other clinical manifestations are infrequent: arthromyalgias, cutaneous rash, sweating, splenomegaly. Leukopenia is prese nt in 50% of the cases with sometimes "atypical" lymphocytes. A spontaneous ly favorable outcome is noted after a mean 3 months. Histopathology of the lymph node is the key for the diagnosis of KFD showin g lymph node necrosis of 25 to 75% of the surface, in the cortex and the me dulla of the lymph nodes with histiocytic proliferation and plasma cells. H istochemistry shows positive straining for monocytic markers (CD68+, KiM1P). Alpha-beta CD8+ T cells are abundant, NK and B cells are scarce. Patholo gical examination enables to differentiate KFD from other types of necrotiz ing lymphadenitis (SLE, malignant lymphoma, pyogenic infections). Kikuchi d isease can be the result of local hyperimmune stimulation after viral, bact erial or parasitic infection. CD4+ cells would then become apoptotic cells. In some cases KJD is associated with systemic diseases such as systemic lu pus erythematosus or adult Stilt's disease.