Kikuchi's histiocytic necrotizing lymphadenitis: an analysis of 108 cases with emphasis on differential diagnosis.

Kikuchi's necrotizing lymphadenitis has now become recognized in many parts of the world as a well-defined clinicopathologic entity with a remarkable predilection for cervical lymph nodes of young women. The morphologic features encountered in lymph nodes are distinctive and should enable pathologists to establish the diagnosis with confidence. Nonetheless, this analysis of 108 cases, encountered over a 15-year period, has emphasized the difficulty that many pathologists have in recognizing this disorder, and in particular, in distinguishing it from malignant lymphoma. Although in the vast majority of cases, lymphadenopathy and other symptomatology resolves spontaneously, two of our patients, thought initially to have Kikuchi's disease, developed systemic lupus erythematosus. This raises consideration for the proposal that Kikuchi's disease may reflect a self-limited SLE-like auto-immune condition (a "forme fruste" of SLE), perhaps induced by virus-infected transformed lymphocytes. Moreover, such observations indicate that patients with Kikuchi's disease should be kept under observation for several years to ensure that they are not at risk for the development of systemic lupus erythematosus.