Sarcoidosis. Retroperitoneal fibrosis, renal arterial involvement, and unilateral focal glomerulosclerosis

In one patient with pulmonary sarcoidosis, hypertension occurred during the course of the disease. Aortography showed extensive narrowing of the right renal artery. Surgical exploration disclosed extensive periaortic and perirenal fibrosis. This fibrosis encircled the right renal artery and caused extrinsic compression. Pathological examination disclosed a large amount of histiocyte epithelioid infiltration in various samples of the fibrosis and particularly in the adventitia of the renal artery, highly suggestive of sarcoidal angiitis. Surgical biopsy was performed on both kidneys. The right kidney, protected by arterial stenosis, was little altered, while the left kidney showed extensive interstitial, tubular, and glomerular lesions. The glomerular lesions were focal and segmental hyalinosis.