Longitudinal analysis of serum KL-6 levels in patients with systemic sclerosis: association with the activity of pulmonary fibrosis

Clin Exp Rheumatol. 2003 Jul-Aug;21(4):429-36.


Objective: To determine whether changes in serum KL-6 levels reflect the activity of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc).

Methods: KL-6 levels were determined by ELISA in 39 SSc patients. In a retrospective longitudinal study, 250 serum samples were analyzed during a follow-up period of 0.3-6.1 years.

Results: KL-6 levels at the first visit were higher in patients with SSc, especially with PF, compared with healthy controls. In the longitudinal study, KL-6 levels in 4 patients with anti-topo I Abs increased rapidly, parallel to the progression of PF. Four patients with inactive PF exhibited elevated, but stable levels of KL-6 during the follow-up. The 31 patients with almost normal KL-6 levels during the follow-up exhibited no deterioration or new onset of PF.

Conclusion: Rapidly increased serum KL-6 levels during disease course were associated with new onset or deterioration of PF.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Analysis of Variance
  • Antigens / blood*
  • Antigens, Neoplasm
  • Biomarkers / blood
  • Disease Progression
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Glycoproteins / blood*
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Mucin-1
  • Mucins
  • Probability
  • Prognosis
  • Pulmonary Fibrosis / blood*
  • Pulmonary Fibrosis / complications*
  • Pulmonary Fibrosis / diagnosis
  • Retrospective Studies
  • Scleroderma, Systemic / blood*
  • Scleroderma, Systemic / complications*
  • Scleroderma, Systemic / diagnosis
  • Sensitivity and Specificity
  • Severity of Illness Index
  • Statistics, Nonparametric
  • Tomography, X-Ray Computed


  • Antigens
  • Antigens, Neoplasm
  • Biomarkers
  • Glycoproteins
  • MUC1 protein, human
  • Mucin-1
  • Mucins