title: The ultrastructural patterns of mast cell degranulation in Kimura's disease.
abstract: BACKGROUND
  Although Kimura's disease has been considered an atopic disease because of the association of peripheral blood eosinophilia and elevated serum IgE, the mechanisms of these phenomena are still unknown.
  
  
  OBJECTIVE
  It is now established that mast cells are a source of cytokines that are involved in eosinophil recruitment or IgE production. In order to understand the role of mast cells in Kimura's disease, we conducted ultrastructural studies.
  
  
  METHODS
  The 45 mast cells obtained from 2 patients with Kimura's disease were classified into two subgroups: S type, with a predominance of scroll or crystal subelements in their granules, and P type, predominantly possessing a particulate or filamentous substructure.
  
  
  RESULTS
  We observed numerous P type mast cells with focal losses of granule contents in the absence of granule extrusion in Kimura's disease.
  
  
  CONCLUSIONS
  These results indicate the possibility that slow release of mediators or cytokines from mast cells by piecemeal degranulation may contribute to the pathomechanism of Kimura's disease.
authors.affiliation: Department of Dermatology, Nippon Medical School Main Hospital, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Aoki
authors.forename: S
authors.initials: S
authors.lastname: Kawana
mesh_terms: D000328:Adult; D000796:Angiolymphoid Hyperplasia with Eosinophilia / Q000473:pathology*; D015550:Cell Degranulation; D005260:Female; D006801:Humans; D008297:Male; D008407:Mast Cells / Q000502:physiology / Q000648:ultrastructure*; D008875:Middle Aged; D012867:Skin / Q000473:pathology / Q000648:ultrastructure