Rheumatoid pneumoconiosis

Greaves lA. 1979. Rheumatoid "pneumoconiosis" (Caplan s syndrome) in an asbestos worker A 17 years follow-up. Thorax 34 404-405. 

Rheumatoid Pneumoconiosis (Caplan s Syndrome) Rheumatoid pneumoconiosis occurs in miners with circulating rheumatoid factor but not necessarily evidence of arthritis. It is also seen in workers exposed to silica (Caplan et al. 1962). Radiographic examination typically shows rapidly enlarging, circumscribed nodules ranging in size... 

Microscopically, rheumatoid pneumoconiotic lesions are similar to rheumatoid nodules occurring in the lungs of non-occupationally exposed individuals, except for the presence of rings of coal dust, frequently around the periphery. The central zone is eosinophilic and necrotic, and there is usually a layer of palisaded fibroblasts and macrophages (Wagner and McCormick 1967). It is crucial to rule out infections, particularly tuberculosis, before making a diagnosis of rheumatoid pneumoconiosis. 

Complicated pneumoconiosis (massive fibrosis) Rheumatoid pneumoconiosis (Caplan s syndrome) Lung cancer ... 

Rheumatoid Pneumoconiosis Rheumatoid pneumoconiosis or Caplan s syndrome is seen in workers with silica exposure as well as those with coal exposure. Apart from the presence of coal pigment in the lesions in coal workers, the conditions are quite similar in their pathological and radiological appearances (Section 2.1.3). 

Hoffmann EO, Lamberty J, Pizzolato P et al (1973) The ultrastructure of acute silicosis. Arch Pathol 96 104-107 Honma K, Vallyathan V (2002) Rheumatoid pneumoconiosis a comparative study of autopsy cases between Japan and North America. Ann Occup Hyg 465 265-267 Honma K, Abraham JL, Chiyotani K et al (2004) Proposed criteria for mixed-dust pneumoconiosis definition, descriptions, and guidelines for pathologic diagnosis and clinical correlation. Hum Pathol 35 1515-1523 Hughes JM, Jones RN, Gilson JC et al (1982) Determinants of progression in sandblasters silicosis. Ann Occup Hyg 26 701-712... 

A major contribution of the free-radical scavenging activity in blood plasma is attributable to the macro-molecular proteins (Wayner et al., 1985) of which albumin is a primary component and trapping agertt (Holt et al., 1984). Serum sulphydryl levels, primarily albumin-related, are decreased in subjects with rheumatoid complicated coalworkers pneumoconiosis, indicative of exacerbated inflammatory R.OM production (Thomas and Evans, 1975). Experimental asbestos inhalation in rats leads to an adaptive but evidendy insufficient response by an increase in endogenous antioxidant enzymes (Janssen etal., 1990). Protection of the vascular endothelium against iron-mediated ROM generation and injury is afforded by the iron sequestiant protein ferritin (Balia et al., 1992). 

Evans, P.H. (1977). Serum sulphydryl changes in rheumatoid coalworkers pneumoconiosis patients treated with D-penicillamine. Proc. Roy. Soc. Med. 70, (S3), 95-97. 

Constantinidis K. 1977. Pneumoconiosis and rheumatoid arthritis (Caplan s syndrome). BrJClinPract 31 25-31. 

Recently, a case of MCTD in a male patient occupationally exposed to PVC and other toxic agents was presented. Clinical symptoms consisted of typical signs of systemic LE, rheumatoid arthritis, and lupoid hepatitis. MCTD diagnosis was confirmed serologically by the presence of u i-ribonucleoprotein-autoantibo-dies. Prednisone, 60 mg daily, produced remission (Panaszek et al. 1993). Studnicka et al. (1995) presented a 58-year-old patient exposed to thermoplastic dusts, mainly PVC, for 10 years. He developed pneumoconiosis and secondary SSc. 

When the rheumatoid pulmonary nodules appear in patients with pneumoconiosis, a diffuse nodular fibrotic process, called Caplan s syndrome, may develop. 

The syndrome, as first described by Caplan, is defined as multiple, large (0.5-5 cm diameter), round, radiographic opacities frequently associated with evidence of cavity formation or calcification, usually unaccompanied by the small opacities of simple pneumoconiosis, in coal miners with rheumatoid arthritis (Caplan 1959). This concept has been broadened to the occurrence of radiographic opacities in the absence of rheumatoid arthritis but associated with circulating rheumatoid factor... 

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