title: Clinical, serologic, and immunogenetic characterization (HLA-DRB1) of late-onset lupus erythematosus in a Colombian population.
abstract: BACKGROUND
  Late-onset systemic lupus erythematosus (SLE) represents a specific subgroup that is defined as onset after 50 years of age. Late-onset lupus may have a different clinical course and serological findings, which may delay diagnosis and timely treatment.
  
  
  OBJECTIVE
  The objective of this paper is to determine the clinical, serologic, and immunogenetic differences among Colombian patients with late-onset SLE versus conventional SLE patients.
  
  
  METHODS
  This was a cross-sectional study in a Colombian population. Patients and their medical records were analyzed from the services of Rheumatology in Bogotá and met the criteria for SLE, according to the American College of Rheumatology (ACR) revised criteria for the classification of SLE.In a reference group of late-onset SLE patients (98 participants, with an onset after 50 years of age) and a group of conventional SLE patients (72 participants, with an onset of age of 49 years or less), multiple clinical variables (age, clinical criteria for lupus, alopecia, weight loss, fever, Raynaud's phenomenon) and multiple serological variables (blood count, blood chemistry profile, autoantibodies) were analyzed. Additionally, the HLA class II (DRB1) of all the patients was genotyped, including an additional group of patients without the autoimmune disease. Statistical analysis was performed using the STATA 10.0 package.
  
  
  RESULTS
  In the group of late-onset lupus, there was a higher frequency of pleurisy (p = 0.002), pericarditis (p = 0.026), dry symptoms (p = 0.029), lymphopenia (p = 0.007), and higher titers of rheumatoid factor (p = 0.001) compared with the group of conventional SLE. Late-onset SLE patients had a lower seizure frequency (p = 0.019), weight loss (p = 0.009), alopecia (p < 0.001), and Raynaud's phenomenon (p = 0.013) compared to the conventional SLE group. In late-onset SLE, HLA DR17 (DR3) was found more frequently compared with individuals without autoimmune disease (OR 3.81, 95% CI 1.47 to 10.59) (p = 0.0016).
  
  
  CONCLUSIONS
  In the Colombian SLE population analyzed, there may be a probable association of several clinical and serologic variants, which would allow the differentiation of variables in the presentation of the disease among patients with late-onset SLE vs. conventional SLE.
authors.affiliation: Rheumatology Unit, National University of Colombia, Bogotá, Colombia.
authors.forename: E
authors.initials: E
authors.lastname: Peñaranda-Parada
authors.affiliation: Rheumatology Unit, National University of Colombia, Bogotá, Colombia.
authors.forename: G
authors.initials: G
authors.lastname: Quintana
authors.affiliation: Unit of Genetics, National University of Colombia, Bogotá, Colombia.
authors.forename: J J
authors.initials: JJ
authors.lastname: Yunis
authors.affiliation: Rheumatology Unit, National University of Colombia, Bogotá, Colombia.
authors.forename: R
authors.initials: R
authors.lastname: Mantilla
authors.affiliation: Rheumatology Unit, National University of Colombia, Bogotá, Colombia.
authors.forename: W
authors.initials: W
authors.lastname: Rojas
authors.affiliation: Rheumatology Unit, National University of Colombia, Bogotá, Colombia.
authors.forename: U
authors.initials: U
authors.lastname: Panqueva
authors.affiliation: Unit of Biochemistry, National University of Colombia, Bogotá, Colombia.
authors.forename: J E
authors.initials: JE
authors.lastname: Caminos
authors.affiliation: Unit of Biochemistry, National University of Colombia, Bogotá, Colombia.
authors.forename: M F
authors.initials: MF
authors.lastname: Garces
authors.affiliation: Unit of Biochemistry, National University of Colombia, Bogotá, Colombia.
authors.forename: E
authors.initials: E
authors.lastname: Sanchez
authors.affiliation: Rheumatology Unit, National University of Colombia, Bogotá, Colombia.
authors.forename: F
authors.initials: F
authors.lastname: Rondón-Herrera
authors.affiliation: Rheumatology Unit, National University of Colombia, Bogotá, Colombia iglesias.antonio1@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: de Jesús Iglesias-Gamarra
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood; D003105:Colombia; D003430:Cross-Sectional Studies; D005260:Female; D005838:Genotype; D059811:HLA-DRB1 Chains / Q000235:genetics*; D006801:Humans; D007125:Immunogenetics; D008180:Lupus Erythematosus, Systemic / Q000453:epidemiology* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D059811:HLA-DRB1 Chains
keywords: Systemic lupus erythematosus (SLE); human leukocyte antigen DRB1 (HLA-DRB1); late-onset lupus