title: Rheumatoid arthritis-associated interstitial lung disease: lung inflammation evaluated with high resolution computed tomography scan is correlated to rheumatoid arthritis disease activity.
abstract: OBJECTIVE
  To describe the association between rheumatoid arthritis disease activity (RA) and interstitial lung damage (inflammation and fibrosis), in a group of patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD).
  
  
  METHODS
  A retrospective study of RA patients with interstitial lung disease (restrictive pattern in lung function tests and evidence of interstitial lung disease in high resolution computed tomography (HRCT)). Patients were evaluated to exclude other causes of pulmonary disease. RA disease activity was measured with the CDAI index. Interstitial lung inflammation and fibrosis were determined by Kazerooni scale. We compared Kazerooni ground-glass score with the nearest CDAI score to HRCT date scan of the first medical evaluation at our institution. In nine patients, we compared the first ground-glass score with a second one after treatment with DMARDs and corticosteroids. Spearman's rank correlation coefficient was used to evaluate association between RA disease activity and the Kazerooni ground-glass and fibrosis scores.
  
  
  RESULTS
  Thirty-four patients were included. A positive correlation between CDAI and ground-glass scores was found (rs=0.3767, P<0.028). Fibrosis and CDAI scores were not associated (rs=-0.0747, P<0.6745). After treatment, a downward tendency in the ground-glass score was observed (median [IQR]): (2.33 [2,3] vs. 2 [1.33-2.16]), P<0.056, along with a lesser CDAI score (27 [8-43] vs. 9 [5-12]), P<0.063.
  
  
  CONCLUSIONS
  There is a correlation between RA disease activity and ground-glass appearance in the HRCT of RA-ILD patients. These results suggest a positive association between RA disease activity and lung inflammation in RA-ILD.
authors.affiliation: Servicio Clínico de Enfermedades Intersticiales del Pulmón Instituto Nacional de Enfermedades Respiratorias, Ismael Cosío Villegas, Mexico.
authors.forename: Renzo
authors.initials: R
authors.lastname: Pérez-Dórame
authors.affiliation: Servicio Clínico de Enfermedades Intersticiales del Pulmón Instituto Nacional de Enfermedades Respiratorias, Ismael Cosío Villegas, Mexico.
authors.forename: Mayra
authors.initials: M
authors.lastname: Mejía
authors.affiliation: Servicio Clínico de Enfermedades Intersticiales del Pulmón Instituto Nacional de Enfermedades Respiratorias, Ismael Cosío Villegas, Mexico.
authors.forename: Heidegger
authors.initials: H
authors.lastname: Mateos-Toledo
authors.affiliation: Servicio Clínico de Enfermedades Intersticiales del Pulmón, Instituto Nacional de Enfermedades Respiratorias, Ismael Cosío Villegas, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico. Electronic address: jrojas@iner.gob.mx.
authors.forename: Jorge
authors.initials: J
authors.lastname: Rojas-Serrano
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000175:diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000000981:diagnostic imaging / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed
keywords: Artritis reumatoide; Clinical disease activity index; Enfermedad pulmonar intersticial; Enfermedad pulmonar intersticial asociada a la artritis reumatoide; Interstitial lung disease; Kazerooni score; Rheumatoid arthritis; Rheumatoid arthritis associated interstitial lung disease; Índice clínico de actividad de la enfermedad; Índice de Kazerooni