[The immunological aspects of Kikuchi's disease. A clinical case report].

We report a case of histiocytic necrotizing lymphadenitis (NHL) (Kikuchi-Fujimoto disease) in a 23-year-old patient with fever, lymphadenopathy and leukopenia. There were no other significant findings in laboratory data and all bacterial and viral researches were negative. Fever resolved spontaneously after one month, but lymphadenopathy and leukopenia persisted. The immunophenotype of bone marrow and peripheral blood cells showed an increase of B lymphocytes (CD20+, CD21+, CD22+) and activated (CD30+) and NK cells (CD16+, CD56+). This finding persisted after six months. The authors suggest that the clinical feature of NHL is sustained by an immunological substrate.