Elevated serum KL-6 levels in patients with systemic sclerosis: association with the severity of pulmonary fibrosis.
BACKGROUND
Serum KL-6 has been suggested to be a useful marker for the evaluation of interstitial lung disease activity.


OBJECTIVE
To determine the correlation between serum KL-6 levels and pulmonary fibrosis in patients with systemic sclerosis (SSc).


METHODS
Serum samples from patients with limited cutaneous SSc (lSSc; n = 19), diffuse cutaneous SSc (dSSc; n = 26) and normal individuals (n = 15) were examined by ELISA.


RESULTS
Serum KL-6 levels in SSc patients were significantly higher than those in normal controls. KL-6 levels in dSSc patients were significantly elevated compared with those in lSSc patients. Elevated KL-6 levels were associated with the presence of pulmonary fibrosis in SSc patients or dSSc patients. Furthermore, KL-6 levels inversely correlated with percentages of diffusion capacity of carbon monoxide and vital capacity in SSc patients or dSSc patients.


CONCLUSIONS
KL-6 may be a simple, serologic indicator for the severity of pulmonary fibrosis in SSc.
Sato
S
S
Department of Dermatology, Kanazawa University School of Medicine, Kanazawa, Japan. s-sato@med.kanazawa-u.ac.jp
Nagaoka
T
T
Hasegawa
M
M
Nishijima
C
C
Takehara
K
K
D000328:Adult; D000368:Aged; D000974:Antibodies, Antinuclear / Q000032:analysis; D000941:Antigens; D000951:Antigens, Neoplasm; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006023:Glycoproteins; D006801:Humans; D008297:Male; D008875:Middle Aged; D018396:Mucin-1; D009077:Mucins; D010446:Peptide Fragments / Q000097:blood*; D011347:Procollagen / Q000097:blood*; D011658:Pulmonary Fibrosis / Q000097:blood / Q000473:pathology; D012595:Scleroderma, Systemic / Q000097:blood* / Q000473:pathology; D012720:Severity of Illness Index; D013223:Statistics as Topic; D014407:Tumor Cells, Cultured
D000974:Antibodies, Antinuclear; D000941:Antigens; D000951:Antigens, Neoplasm; D006023:Glycoproteins; C060192:MUC1 protein, human; D018396:Mucin-1; D009077:Mucins; D010446:Peptide Fragments; D011347:Procollagen; C041876:procollagen Type III-N-terminal peptide