Serum KL-6 concentrations in dairy farmers.
OBJECTIVE
Serum KL-6 (Krebs von den Lungen-6) has been recognized to be a marker for the activity of diffuse interstitial lung diseases. The purpose of the study is to evaluate serum KL-6 measurement as a marker for farmer's lung disease (FLD).


METHODS
A cross-sectional survey of a cohort of dairy farmers. Retrospective measurement of KL-6 stored serum samples from those dairy farmers previously screened for FLD.


METHODS
University hospital screening project for FLD within a dairy-farming community in Japan.


METHODS
Four hundred seventy-two dairy farmers were invited to attend a local clinic.


RESULTS
We examined serum KL-6 concentrations in 272 farmers. Subjects were classified into three groups: (1) 5 farmers with FLD, (2) 30 farmers with positive serum precipitating antibodies to Saccharopolyspora rectivirgula and/or Thermoactinomyces vulgaris without FLD (Ab(+)), and (3) 237 farmers without these antibodies (Ab(-)). Serum KL-6 concentrations in the FLD group were significantly higher than those in the Ab(+) and the Ab(-) groups (1,263 +/- 288 [SEM], 328 +/- 57, and 207 +/- 6 U/mL, respectively, p < 0.001). Serum KL-6 concentrations in those with FLD were significantly higher than KL-6 concentrations from stored screening samples from the same individual when FLD was not diagnosed (1,263 +/- 288 and 419 +/- 209 U/mL, respectively, p < 0.05). Serum KL-6 concentrations of the Ab(+) group were significantly higher than those of the Ab(-) group (p < 0.001). In the Ab(+) group, farmers with high serum KL-6 concentrations had lower permeability coefficients than farmers with normal serum KL-6 concentrations (p < 0.05). These results may suggest that subclinical FLD can be detected in farmers with high KL-6 concentrations and precipitating antibodies.


CONCLUSIONS
Serum KL-6 concentration can be a useful marker for assessing the activity of FLD and may be able to be used to detect subclinical disease.
Takahashi
T
T
First Department of Medicine, Satoh-Kamachi, Sato, School of Medicine, Hokkaido University, Sapporo, Japan.
Munakata
M
M
Ohtsuka
Y
Y
Satoh-Kamachi
A
A
Sato
R
R
Homma
Y
Y
Kawakami
Y
Y
D000192:Actinomycetales / Q000276:immunology; D000822:Animal Husbandry; D000908:Antibodies, Fungal / Q000032:analysis; D000941:Antigens; D000951:Antigens, Neoplasm; D015415:Biomarkers / Q000097:blood; D005203:Farmer's Lung / Q000097:blood* / Q000453:epidemiology / Q000276:immunology; D005260:Female; D006023:Glycoproteins; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D018396:Mucin-1; D009077:Mucins; D016273:Occupational Exposure / Q000009:adverse effects*; D010446:Peptide Fragments / Q000097:blood*; D011347:Procollagen / Q000097:blood*; D012189:Retrospective Studies; D012424:Rural Population; D011795:Surveys and Questionnaires
D000908:Antibodies, Fungal; D000941:Antigens; D000951:Antigens, Neoplasm; D015415:Biomarkers; D006023:Glycoproteins; C060192:MUC1 protein, human; D018396:Mucin-1; D009077:Mucins; D010446:Peptide Fragments; D011347:Procollagen; C041876:procollagen Type III-N-terminal peptide