Stonemason's systemic vasculitis: three cases and a dilemma.

A 37-year-old man presented to his GP in July 1987 complaining of a 1-month history of a blocked nose and oral ulceration. He had worked as a quarryman for several years, often in the same quarry as cases 2 and 3. During this time, he was exposed to dust from silicarich sandstone. A nasal biopsy showed ulceration consistent with Wegener’s granulomatosis. He had dipstick haematuria and proteinuria. cANCA was positive at 1:80; serum urea and creatinine were normal. A renal biopsy was normal to light microscopy, with negative immunoflouresence, but showed mesangial proliferative changes on electron microscopy. Treatment was started with daily oral prednisolone 60mg and cyclophosphamide 150mg. The immunosuppression was tailed over the next year and renal function remained normal. Treatment was discontinued after 24 months and he has remained in remission for the last 13 years. He has continued to work as a quarryman in a wide range of quarries in North East England. Some of these quarries contain silica-rich stone and others are silica free. Case 2