title: Diagnosis of latent tuberculosis in patients with systemic lupus erythematosus: T.SPOT.TB versus tuberculin skin test.
abstract: Early studies in patients with systemic lupus erythematosus (SLE) reported increased incidence of tuberculosis. The tuberculin skin test (TST) is the technique of choice to detect latent tuberculosis infection (LTBI) but has several limitations.
  
  
  OBJECTIVE
  We compared TST and the newer T.SPOT.TB test to diagnose LTBI in SLE patients.
  
  
  METHODS
  In this observational cohort study conducted between August 2009 and February 2012, we recruited 92 patients from those attending the SLE clinic of our university hospital. Data recorded were epidemiological and sociodemographic characteristics. Laboratory analyses included TST and T.SPOT.TB tests.
  
  
  RESULTS
  Of the patients studied, 92% were women with an average age of 42.7 years. Overall, the degree of correlation between the two tests was low (Kappa index = 0.324) but was better in patients not receiving corticosteroids (CTC)/immunosuppressive (IS) therapy (Kappa = 0.436) and in those receiving hydroxychloroquine (Kappa = 0.473). While TST results were adversely affected by those receiving CTC and/or IS drugs (P = 0.021), the T.SPOT.TB results were not.
  
  
  CONCLUSIONS
  Although the TST test remains a useful tool for diagnosing LTBI in SLE patients, the T.SPOT.TB test is perhaps better employed when the patient is receiving CTC and/or IS drugs.
authors.affiliation: Department of Internal Medicine, University Hospital Virgen de las Nieves, Avenida de las Fuerzas Armadas No. 2, 18004 Granada, Spain.
authors.forename: Maria Del Mar
authors.initials: Mdel M
authors.lastname: Arenas Miras
authors.affiliation: Department of Infectious Diseases, University Hospital Virgen de las Nieves, Avenida de las Fuerzas Armadas No. 2, 18004 Granada, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Hidalgo-Tenorio
authors.affiliation: Department of Clinical Analysis, University Hospital Virgen de las Nieves, Avenida de las Fuerzas Armadas No. 2, 18004 Granada, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Jimenez-Gamiz
authors.affiliation: Department of Internal Medicine, University Hospital Virgen de las Nieves, Avenida de las Fuerzas Armadas No. 2, 18004 Granada, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Jiménez-Alonso
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D055985:Latent Tuberculosis / Q000150:complications* / Q000175:diagnosis*; D008180:Lupus Erythematosus, Systemic / Q000150:complications* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014374:Tuberculin Test / Q000295:instrumentation* / Q000379:methods*