title: [Blood groups and discoid lupus erythematosus].
abstract: BACKGROUND
  Discoid lesion is the commonest cutaneous finding in lupus erythematosus and chronic types have their own immunological features, with Th1 inflammation profile. Although many diseases have association with blood-group systems, this fact was not enlightened in discoid lupus erythematosus.
  
  
  OBJECTIVE
  To investigate the association between blood groups (ABO and Rh) and discoid lupus erythematosus.
  
  
  METHODS
  A prospective cross-sectional study assessing clinical information, blood group systems (ABO and Rh), FAN and C4 serum levels from discoid lupus patients without characteristics of systemic disease, was carried out at a clinic from a Brazilian university hospital.
  
  
  RESULTS
  Sixty-nine patients were enrolled in the study, 71.0% were females (p1:160 in 31.9%, and low levels of C4 in 8.7%. There was no significant difference between the frequency of blood groups from discoid lupus patients and local population, however, blood group A was associated to disseminate forms of the disease (OR 4.1 and p < 0.05).
  
  
  CONCLUSIONS
  Discoid lupus erythematosus patients with ABO and Rh blood groups exhibit similar frequencies as in the general population; nevertheless, disseminate clinical forms were more prevalent among group A patients.
authors.affiliation: serviço de dermatologia, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, SP, Brasil.
authors.forename: Andréia de Almeida
authors.initials: Ade A
authors.lastname: Tamega
authors.forename: Lílian Valéria Guerra da Silva Pinto
authors.initials: LV
authors.lastname: Bezerra
authors.forename: Fabíola de Paula
authors.initials: Fde P
authors.lastname: Pereira
authors.forename: Hélio Amante
authors.initials: HA
authors.lastname: Miot
mesh_terms: D000017:ABO Blood-Group System; D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008179:Lupus Erythematosus, Discoid / Q000097:blood*; D008297:Male; D011446:Prospective Studies; D012204:Rh-Hr Blood-Group System
chemical_list: D000017:ABO Blood-Group System; D012204:Rh-Hr Blood-Group System