Antimyeloperoxidase antibodies in individuals with occupational exposure to silica.
OBJECTIVE
To determine the prevalence of autoantibodies to myeloperoxidase (MPO) in a series of patients exposed to silica.


METHODS
The study included 52 patients with occupational exposure to silica (mean exposure time seven years) and a control group comprising seven patients with progressive systemic sclerosis (PSS), six patients with systemic lupus erythematosus (SLE), and 15 healthy individuals. Antibodies to MPO were detected using commercial enzyme linked immunosorbent assay (ELISA) plates coated with MPO. Indirect immunoflurescence studies for antineutrophil cytoplasmic antibodies were performed using ethanol and formol fixed neutrophils. Clinical and biological data of individuals exposed to silica were recorded (published previously).


RESULTS
Antibodies to MPO were detected in 14 individuals exposed to silica (27%). There was a statistically significant difference in anti-MPO ELISA units between the healthy subjects and patients (SLE, PSS, silica exposed individuals) (p < 0.01), but no difference between the different disease groups.


CONCLUSIONS
Individuals chronically exposed to silica, whether or not they have a connective tissue disease, have levels of antibodies to MPO (as detected by ELISA) that are greater than those found in the normal population, but similar to those in patients with systemic diseases not induced by silica (SLE/PSS).
Wichmann
I
I
Servicio de Inmunología and Unidad de Colagenosis, Hospital Universitario Virgen del Rocío, Sevilla, Spain.
Sanchez-Roman
J
J
Morales
J
J
Castillo
M J
MJ
Ocaña
C
C
Nuñez-Roldan
A
A
D019268:Antibodies, Antineutrophil Cytoplasmic; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D003240:Connective Tissue Diseases / Q000209:etiology / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007221:Industry; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D009784:Occupational Diseases / Q000209:etiology / Q000276:immunology*; D016273:Occupational Exposure / Q000009:adverse effects; D009195:Peroxidase / Q000276:immunology*; D012595:Scleroderma, Systemic / Q000276:immunology; D012822:Silicon Dioxide / Q000009:adverse effects*
D019268:Antibodies, Antineutrophil Cytoplasmic; D001323:Autoantibodies; D015415:Biomarkers; D012822:Silicon Dioxide; D009195:Peroxidase