title: Immunogenetic similarities between patients with Felty's syndrome and those with clonal expansions of large granular lymphocytes in rheumatoid arthritis.
abstract: OBJECTIVE
  Patients with chronic clonal proliferation of large granular lymphocytes (LGL leukemia) often have splenomegaly, neutropenia, and rheumatoid arthritis (RA), thereby resembling the manifestations observed in patients with Felty's syndrome. The present study sought to determine whether patients with these disorders represent 2 distinct subsets of neutropenic RA.
  
  
  METHODS
  Prospective cohort study of outpatients attending clinics in university and private hospitals and in offices of private practice physicians. Twenty-two patients with Felty's syndrome and 22 patients with LGL leukemia, 10 of whom had RA, were studied. HLA genotyping was performed on peripheral blood mononuclear leukocyte genomic DNA.
  
  
  RESULTS
  Nineteen of the 22 patients with Felty's syndrome (86%) were DR4 positive. Nine of the 10 patients with LGL leukemia plus RA were also DR4 positive. In contrast, only 4 of the 12 patients with LGL leukemia without RA (33%) were DR4 positive, a frequency that was within the normal range.
  
  
  CONCLUSIONS
  The finding of an equally high prevalence of DR4 in patients with Felty's syndrome and in those with LGL leukemia plus RA suggests that both disorders have a similar immunogenetic basis and are parts of a single disease process rather than 2 separate disorders.
authors.affiliation: VA Medical Center and University of Washington, Seattle, USA.
authors.forename: G
authors.initials: G
authors.lastname: Starkebaum
authors.forename: T P
authors.initials: TP
authors.lastname: Loughran
authors.forename: L K
authors.initials: LK
authors.lastname: Gaur
authors.forename: P
authors.initials: P
authors.lastname: Davis
authors.forename: B S
authors.initials: BS
authors.lastname: Nepom
mesh_terms: D001172:Arthritis, Rheumatoid / Q000235:genetics / Q000276:immunology*; D002999:Clone Cells / Q000276:immunology; D015331:Cohort Studies; D005258:Felty Syndrome / Q000235:genetics / Q000276:immunology*; D005838:Genotype; D015804:HLA-DR4 Antigen / Q000235:genetics*; D006801:Humans; D007125:Immunogenetics; D007945:Leukemia, Lymphoid / Q000235:genetics / Q000276:immunology*; D011446:Prospective Studies
chemical_list: D015804:HLA-DR4 Antigen