title: Histopathology and correlates of systemic disease in adult Henoch-Schönlein purpura: a retrospective study of microscopic and clinical findings in 68 patients at Mayo Clinic.
abstract: BACKGROUND
  The histopathology of Henoch-Schönlein purpura (HSP) is well defined, but specific markers have not been correlated with systemic involvement.
  
  
  OBJECTIVE
  We sought to evaluate whether histopathologic markers were associated with renal or other systemic involvement in adult HSP.
  
  
  METHODS
  We retrospectively reviewed clinical information and pathology slides of 68 adult patients with HSP seen at Mayo Clinic between 1992 and 2011.
  
  
  RESULTS
  Of the 68 patients, mean age was 45.8 years and 41 (60%) of the patients were male. Renal involvement was observed in 30 patients (44%), gastrointestinal tract in 27 (40%), joint in 32 (47%), and any systemic signs in 52 (76%). Patients who were older than 40 years and had leukocytoclastic vasculitis with an absence of eosinophils on skin biopsy specimen had higher rates of renal involvement than those who did not have both of these features (75% vs 27%; P < .001). Patients with skin biopsy specimens showing leukocytoclastic vasculitis and an absence of histiocytes had higher rates of gastrointestinal tract involvement (P = .03). Age of 40 years or younger was associated with increased risk for gastrointestinal tract involvement and a nonsignificant trend for joint involvement (P = .004 and P = .06, respectively).
  
  
  CONCLUSIONS
  This study is retrospective, and the causative factors of HSP were unable to be determined in many patients.
  
  
  CONCLUSIONS
  Patients older than 40 years with HSP who had an absence of eosinophils on skin biopsy specimen had a nearly 3-times increased risk of renal involvement compared with patients who did not have both features.
authors.affiliation: Mayo Medical School, College of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Poterucha
authors.forename: David A
authors.initials: DA
authors.lastname: Wetter
authors.forename: Lawrence E
authors.initials: LE
authors.lastname: Gibson
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Camilleri
authors.forename: Christine M
authors.initials: CM
authors.lastname: Lohse
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005767:Gastrointestinal Diseases / Q000209:etiology; D006801:Humans; D011695:IgA Vasculitis / Q000150:complications / Q000473:pathology*; D007070:Immunoglobulin A / Q000032:analysis; D007592:Joint Diseases / Q000209:etiology; D007674:Kidney Diseases / Q000209:etiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018366:Vasculitis, Leukocytoclastic, Cutaneous / Q000209:etiology
chemical_list: D007070:Immunoglobulin A