title: Revisiting clinical differences between hypersensitivity vasculitis and Henoch-Schönlein purpura in adults from a defined population.
abstract: OBJECTIVE
  Hypersensitivity vasculitis (HV) and Henoch-Schönlein purpura (HSP) are the most common entities included within the category of cutaneous vasculitis (CV). Palpable purpura and histological changes characterised by the presence of leukocytoclastic vasculitis are common in both conditions. Therefore, considerable overlap between them is often seen. It is especially true when the CV occurs in adults. To further establish clinical differences between these two conditions, in the present study we assessed the main clinical differences between HV and HSP in a wide and unselected series of adults with CV from a defined population.
  
  
  METHODS
  We reviewed the clinical records of 297 consecutive adults (age >20 years) seen at a single centre between January 1975 and December 2012 that were classified as having HSP or HV according to the criteria proposed by Michel et al. (J Rheumatol 1992; 19: 721-8).
  
  
  RESULTS
  Based on the inclusion criteria, 102 adult patients (71 men/31 women) were classified as HSP and 195 (104 men/91 women) as HV. The mean age was similar in both groups (55.8±16.5 years in HSP and 56.8±18.3 years in HV). Precipitating events, usually an upper respiratory tract infection and/or drug intake, were more frequently observed in HV. Both at the beginning of the disease and when the CV was established clinical manifestations were more frequent in patients with HSP than in those with HV. It was the case for gastrointestinal (57.4% vs. 6.8%; p<0.001), joint (51.5% vs. 36.6%; p=0.01) and renal involvement (86.3% vs. 18.3%; p<0.001). Corticosteroid (56.7% vs. 22%; p<0.001) and cytotoxic drug (19.4% vs. 3.2%; p<0.001) use was also more common in patients with HSP. After a median follow-up of 15.5 (interquartile range- IQR; 3-37) months in HSP and 4 (IQR; 2-12) months in HV, the outcome was better in HV than in HSP. In this regard, complete recovery (72.6% vs. 85.4%; p=0.01) was more commonly observed in HV while residual renal involvement (15.3% vs. 4.2%; p<0.001) was more common in HSP. The disease relapsed in 35.3% of patients with HSP and in 24.4% with HV (p=0.07).
  
  
  CONCLUSIONS
  Our results confirm the claim that these two diseases presenting with similar cutaneous involvement are certainly two separate entities with greater systemic involvement and less favourable outcome in HSP.
authors: Division of Rheumatology, Hospital Universitario Marqués de Valdecilla, IFIMAV, Santander, Spain. fiorelfa@hotmail.com.
authors: Vanesa
authors: V
authors: Calvo-Río
authors: Javier
authors: J
authors: Loricera
authors: Francisco
authors: F
authors: Ortiz-Sanjuán
authors: Cristina
authors: C
authors: Mata
authors: Luis
authors: L
authors: Martín
authors: Lino
authors: L
authors: Alvarez
authors: M Carmen
authors: MC
authors: González-Vela
authors: Javier
authors: J
authors: Rueda-Gotor
authors: Marcos A
authors: MA
authors: González-López
authors: Susana
authors: S
authors: Armesto
authors: Enriqueta
authors: E
authors: Peiró
authors: Manuel
authors: M
authors: Arias
authors: Trinitario
authors: T
authors: Pina
authors: Miguel A
authors: MA
authors: González-Gay
authors: Ricardo
authors: R
authors: Blanco
mesh_terms: D000328:Adult; D017668:Age of Onset; D019411:Clinical Laboratory Techniques; D003937:Diagnosis, Differential; D004342:Drug Hypersensitivity / Q000150:complications*; D005260:Female; D006417:Hematuria / Q000503:physiopathology; D006801:Humans; D011695:IgA Vasculitis / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000276:immunology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D062072:Patient Acuity; D063868:Patient Outcome Assessment; D012141:Respiratory Tract Infections / Q000150:complications*; D012189:Retrospective Studies; D012307:Risk Factors; D012867:Skin / Q000473:pathology*; D013030:Spain / Q000453:epidemiology; D018366:Vasculitis, Leukocytoclastic, Cutaneous / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000276:immunology / Q000503:physiopathology