title: Renal involvement in Henoch-Schönlein purpura: a multivariate analysis of initial prognostic factors.
abstract: OBJECTIVE
  To identify initial predictive factors of renal involvement in children and adolescents with Henoch-Schönlein purpura.
  
  
  METHODS
  We reviewed the medical records of 142 patients admitted to our University Hospital over a 21-year period with a diagnosis of Henoch-Schönlein purpura. The initial predictive factors assessed, observed during the first 3 months, included: demographic data, clinical manifestations (persistent palpable purpura, arthritis, abdominal pain, severe abdominal pain, gastrointestinal bleeding, orchitis, central nervous system involvement and pulmonary hemorrhage), laboratory tests (serum IgA levels) and treatment given (corticosteroids, intravenous immunoglobulin and immunosuppressive drugs). Patients were divided into two groups (presence or absence of nephritis) and assessed by univariate and multivariate analysis.
  
  
  RESULTS
  Evidence of nephritis was detected in 70 patients (49.3%). The univariate analysis revealed that severe abdominal pain (p=0.0049; OR=1.6; 95%CI 1.18-2.21), gastrointestinal bleeding (p=0.004; OR=1.6; 95%CI 1.10-2.26) and corticosteroid use (p=0.0012; OR=1.7; 95%CI 1.28-2.40) were all associated with increased incidence of renal involvement. In the multivariate analysis, logistic regression demonstrated that the only independent variable that predicted nephritis was intense abdominal pain (p<0.012; OR=2.593; 95%CI 1.234-5.452).
  
  
  CONCLUSIONS
  Severe abdominal pain was a significant predictor of nephritis in Henoch-Schönlein purpura. Consequently, pediatric patients exhibiting this clinical manifestation should be rigorously monitored, due to the increased risk of renal involvement.
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo (USP), São Paulo, SP, Brazil.
authors.forename: José Luiz J
authors.initials: JL
authors.lastname: de Almeida
authors.forename: Lúcia Maria A
authors.initials: LM
authors.lastname: Campos
authors.forename: Luciana B
authors.initials: LB
authors.lastname: Paim
authors.forename: Claudio
authors.initials: C
authors.lastname: Leone
authors.forename: Vera Hermínia K
authors.initials: VH
authors.lastname: Koch
authors.forename: Clovis Artur A
authors.initials: CA
authors.lastname: Silva
mesh_terms: D015746:Abdominal Pain / Q000209:etiology*; D000293:Adolescent; D000704:Analysis of Variance; D002648:Child; D005260:Female; D006801:Humans; D011695:IgA Vasculitis / Q000150:complications* / Q000188:drug therapy; D007674:Kidney Diseases / Q000188:drug therapy / Q000209:etiology*; D008297:Male; D009393:Nephritis / Q000209:etiology; D016017:Odds Ratio; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index