title: Autoantibodies in silicosis patients and in silica-exposed individuals.
abstract: The aim of this study was to evaluate the prevalence of autoantibodies in silica-exposed patients with and without silicosis and without any known rheumatic disease. We studied 61 males exposed to silica for a mean time of 12.2 +/- 10.2 years of exposure. A total of 72.1% (44/61) of them presented with pulmonary silicosis. As control group we included 62 healthy males. In all samples we screened for rheumatoid factor (latex agglutination), antinuclear antibodies (indirect immunofluorescence), anti Scl-70 (ELISA) and ANCA (indirect immunofluorescence technique). One patient (1.6%) of the silica group had weakly positive ANA (titer 1:80, centromeric pattern); one (1.6%) had atypical ANCA and seven patients (11.4%) presented positive rheumatoid factor (values range from 8 to 32 UI/ml). One control patient had a positive RF and none of them had positive ANA or ANCA. All patients and controls were negative for anti-Scl-70. The finding of positive RF was higher in the silica-exposed patients (p = 0.032; Fisher). All patients with positive RF had pulmonary silicosis. In the silica-exposed group we could not find a relationship between the presence of RF and age (p = 0.21; Mann-Whitney), smoking habits (p = 0.25; Fisher) but a positive relationship was found with exposure time to silica dust (p = 0.005; Mann-Whitney). We conclude that there was 11.4% prevalence of low titer RF in the silica-exposed patients without known rheumatic disease. RF was more common in patients with longer exposure to silica dust and appeared only in those with silicosis. The presence of ANA, Scl-70 and ANCA was the same as in the control population.
authors.affiliation: Rheumatology Unit, Curitiba's Evangelic University Hospital, Rua João Alencar Guimarães, 796, Curitiba, PR, 80310420, Brazil.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Zaghi
authors.forename: Fábio
authors.initials: F
authors.lastname: Koga
authors.forename: Renato M
authors.initials: RM
authors.lastname: Nisihara
authors.forename: Thelma L
authors.initials: TL
authors.lastname: Skare
authors.forename: Antonieta
authors.initials: A
authors.lastname: Handar
authors.forename: Shirley R
authors.initials: SR
authors.lastname: Rosa Utiyama
authors.forename: Marilia Barreto
authors.initials: MB
authors.lastname: Silva
mesh_terms: D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000096:biosynthesis / Q000097:blood; D000974:Antibodies, Antinuclear / Q000096:biosynthesis / Q000097:blood; D001323:Autoantibodies / Q000096:biosynthesis / Q000097:blood*; D015897:Comorbidity; D004781:Environmental Exposure / Q000009:adverse effects; D056945:Hep G2 Cells; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012216:Rheumatic Diseases / Q000097:blood / Q000453:epidemiology* / Q000276:immunology*; D012217:Rheumatoid Factor / Q000096:biosynthesis / Q000097:blood; D012822:Silicon Dioxide / Q000276:immunology* / Q000506:poisoning; D012829:Silicosis / Q000097:blood / Q000453:epidemiology* / Q000276:immunology*
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D000974:Antibodies, Antinuclear; D001323:Autoantibodies; D012822:Silicon Dioxide; D012217:Rheumatoid Factor
references.citation: Scand J Work Environ Health. 2003 Oct;29(5):329-36
references.pmid: 14584513
references.citation: J Am Med Womens Assoc (1972). 1998 Winter;53(1):21-4, 40
references.pmid: 9458621
references.citation: Arthritis Rheum. 1998 Jul;41(7):1306-11
references.pmid: 9663489
references.citation: J Am Acad Dermatol. 1990 Mar;22(3):444-8
references.pmid: 2155953
references.citation: Acta Biomed. 2005;76 Suppl 2:38-44
references.pmid: 16350548
references.citation: J Am Soc Nephrol. 2001 Jan;12(1):134-142
references.pmid: 11134259
references.citation: Am J Ind Med. 1999 Aug;36(2):299-306
references.pmid: 10398938
references.citation: Sci Total Environ. 2001 Apr 10;270(1-3):141-8
references.pmid: 11327387
references.citation: Clin J Am Soc Nephrol. 2007 Mar;2(2):290-9
references.pmid: 17699427
references.citation: Int J Immunopathol Pharmacol. 2006 Apr-Jun;19(2):357-68
references.pmid: 16831302
references.citation: Cell Mol Immunol. 2007 Aug;4(4):261-8
references.pmid: 17764616
references.citation: Curr Opin Rheumatol. 1998 Jan;10(1):12-7
references.pmid: 9448985
references.citation: Occup Environ Med. 2002 Aug;59(8):545-9
references.pmid: 12151611
references.citation: Clin Exp Rheumatol. 2007 May-Jun;25(3):443-8
references.pmid: 17631742
references.citation: Kidney Int. 2005 May;67(5):1961-6
references.pmid: 15840044
references.citation: J Rheumatol. 2007 Jan;34(1):43-9
references.pmid: 17143972
references.citation: Clin Rev Allergy Immunol. 1997 Spring;15(1):21-40
references.pmid: 9209799
references.citation: Curr Opin Pulm Med. 2000 Mar;6(2):151-6
references.pmid: 10741776
references.citation: Nephrol Dial Transplant. 1996 Sep;11(9):1835-8
references.pmid: 8918632
references.citation: Mol Cell Biochem. 2002 May-Jun;234-235(1-2):219-24
references.pmid: 12162437
references.citation: Rheumatology (Oxford). 2004 Nov;43(11):1424-8
references.pmid: 15328423
references.citation: Joint Bone Spine. 2002 Jan;69(1):68-71
references.pmid: 11858360
references.citation: Nephron. 1989;51(4):544-7
references.pmid: 2567970
references.citation: Am J Respir Crit Care Med. 2002 Mar 1;165(5):690-3
references.pmid: 11874815
references.citation: Toxicology. 2004 Feb 15;195(2-3):167-76
references.pmid: 14751672
references.citation: Exp Biol Med (Maywood). 2006 May;231(5):522-33
references.pmid: 16636300
references.citation: Minerva Med. 1998 Apr;89(4):117-30
references.pmid: 9676177
references.citation: Am Rev Respir Dis. 1991 Aug;144(2):297-301
references.pmid: 1859051
references.citation: Thorax. 1986 Aug;41(8):596-601
references.pmid: 3787543
references.citation: Br J Dermatol. 1990 Dec;123(6):725-34
references.pmid: 2176091
references.citation: Occup Environ Med. 1998 Nov;55(11):779-85
references.pmid: 9924456