Elevated serum-soluble Fas ligand in histiocytic necrotizing lymphadenitis.

Recent studies have indicated that Fas and perforin-based mechanisms seem to induce apoptosis in histiocytic necrotizing lymphadenitis (HNL). In this study, we evaluated the serum levels of soluble Fas ligand (sFasL) in 30 HNL patients using paired sera. Elevations in sFasL levels were detected in 9 patients in the active stage. In the convalescent stage, the levels of sFasL decreased to an undetectable degree after 2 weeks. These findings indicate the possibility that sFasL plays an important role in the constitutional symptoms and pathogenesis of HNL and, furthermore, that it can act as a surrogate marker of the disease activity.