Serum levels of KL-6 reflect disease activity of interstitial pneumonia associated with ANCA-related vasculitis.
OBJECTIVE
KL-6 is reported to be excreted from the lung alveolar and bronchial epithelial cells and may be a good marker for monitoring disease activity of interstitial pneumonia. This study was designed to ascertain the clinical significance of serum KL-6 levels in interstitial pneumonia associated with anti-neutrophil cytoplasmic antibody (ANCA)-related vasculitis.


METHODS
Serum KL-6 levels were determined by an enzyme-linked immunosorbent assay.


METHODS
We examined 20 healthy subjects, 13 patients with perinuclear (myeloperoxidase, MPO) ANCA-related vasculitis and 12 dermatomyositis (DM)/polymyositis (PM) patients as disease controls in this study. Six out of 13 patients with ANCA-related vasculitis had interstitial pneumonia.


RESULTS
Serum levels of KL-6 in ANCA-positive patients with interstitial pneumonia were significantly elevated, while they remained as low as those of healthy subjects in ANCA-positive patients without interstitial pneumonia. Similarly, KL-6 levels in sera were higher in 12 dermatomyositis/polymyositis patients with interstitial pneumonia, while they remained low in DM/PM patients without interstitial pneumonia. Moreover, the elevated serum KL-6 level was reduced during the convalescence induced by glucocorticoid therapy and reflected the disease activity of interstitial pneumonia associated with ANCA-related vasculitis.


CONCLUSIONS
These data suggest that the measurement of serum KL-6 levels may be a good monitoring system for the diagnosis and follow-up of interstitial pneumonia of patients with ANCA-related vasculitis.
Iwata
Y
Y
Department of Gastroenterology and Nephrology, Kanazawa University Graduate School of Medicine.
Wada
T
T
Furuichi
K
K
Kitagawa
K
K
Kokubo
S
S
Kobayashi
M
M
Sakai
N
N
Yoshimoto
K
K
Shimizu
M
M
Kobayashi
K
K
Yokoyama
H
H
D000368:Aged; D000369:Aged, 80 and over; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D000941:Antigens; D000951:Antigens, Neoplasm; D015415:Biomarkers / Q000097:blood; D005260:Female; D006023:Glycoproteins; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000097:blood* / Q000150:complications*; D008297:Male; D008875:Middle Aged; D018396:Mucin-1; D009077:Mucins; D009195:Peroxidase / Q000276:immunology; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D014657:Vasculitis / Q000097:blood* / Q000150:complications* / Q000276:immunology
D019268:Antibodies, Antineutrophil Cytoplasmic; D000941:Antigens; D000951:Antigens, Neoplasm; D015415:Biomarkers; D006023:Glycoproteins; C060192:MUC1 protein, human; D018396:Mucin-1; D009077:Mucins; D009195:Peroxidase