Histiocytic necrotizing lymphadenitis or Kikuchi's disease. Anatomo-clinical study of 4 cases.

Histiocytic necrotizing lymphadentis (HNL) is an uncommon clinical and histologic entity, essentially diagnosed in Japan since 1972. The clinical picture is usually characterized by cervical lymphadenopathy and fever, females being more often affected. Leukopenia and elevated erythrocyte sedimentation rate are frequent. The etiology is still unknown, but a viral origin is most likely. The clinical course is always favorable without treatment, except in one case. The histological picture, with necrotic foci surrounded by histiocytes, immunoblasts, small T lymphocytes and plasmacytoid monocytes (so-called plasmacytoid T cells), is characteristic. Nevertheless, HNL may be mistaken for malignant lymphoma both clinically and histologically. We report 4 cases of HNL. One of these presented severe leukothrombopenia; the serum of this patient significantly suppressed the maturation of granulocytic precursor cells in the bone marrow.