An elderly ‘kawara’ craftsman with acute kidney injury and haemoptysis: a case of silica-induced autoimmunity

A 62-year-old Japanese ‘kawara’ (ceramic roof tile) craftsman presented with acute kidney injury and haemoptysis. This case met the systemic lupus erythematosus and microscopic polyangiitis criteria, with high titres of myeloperoxidase–antineutrophil cytoplasmic antibody (570 EU). Results showed the presence of antinuclear antibody at a high titre (1:2560), but detection of rheumatoid factor, anti-dsDNA, anti-SSA and anti-SSB antibodies was not apparent. This serology was similar to drug-induced, silicon-induced or silica-induced autoimmunity. The patient had been exposed to silica for > 40 years. The environmental aetiology of autoimmune diseases should be considered in cases that show atypical epidemiology and serology.