Histiocytic necrotizing lymphadenitis, Kikuchi-Fujimoto's disease, associated with systemic lupus erythemotosus.

Histiocytic necrotizing lymphadenitis, Kikuchi-Fujimoto's Disease (KFD), is a condition rarely associated with systemic lupus erythematosus (SLE). The diagnosis of KFD can precede, postdate or coincide with the diagnosis of SLE. Lymphadenopathy is a common clinical presentation of KFD and SLE, and is histologically indistinguishable in both conditions. We describe two cases of KFD associated with SLE. The diagnosis of KFD in one case was made several years before the diagnosis of SLE, and the other was simultaneous. Both showed large lymphadenopathy, but neither fever nor neutropenia. Lymph-node biopsy showed necrosis, with proliferation of histiocytes and immunoblasts, paucity of neutrophils and absence of hemathoxilin bodies. Both patients responded favourably to steroid treatment. Patients with KFD should be assessed for SLE and have long-term follow-up checking for development of SLE. KFD should be ruled out in SLE flare-up accompanied by lymphadenopathy.