[A case of sarcoidosis with renal failure as the main manifestation in granulomatous interstitial nephritis].

A 39-year-old woman was consulted to our hospital because of renal failure on October 1992. A chest X-ray showed no abnormal shadow. Subsequently, she was under conservative treatment until December 1993, when she began to notice clouded vision. The iridocyclitis in both eyes was diagnosed by a ophthalmologist. She was admitted to our hospital for the purpose of a renal biopsy. Laboratory tests revealed renal failure: a creatinine clearance of 24.5 ml/min, a serum level of creatinine of 3.2 mg/ml and blood urea nitrogen of 38.7 mg/dl. The angiotensin converting enzyme was 17.6 IU/ml (normal 8.3 approximately 21.4 IU/ml), but lysozyme was 49.5 micrograms/ml (normal 5.0 approximately 10.2). Mantoux's reaction was negative. 57Ga scintigram showed abnormal uptakes on eyes, bilateral salivary gland, both thighs, both kidneys, and in a part of lung field. A percutaneous renal biopsy revealed non-caseating histiocytic granulomas with diffuse infiltration of lymphocytes and neutrophils into interstitium. Glomeruli were ischemic and mild endocapillary proliferations with pericapsular fibrosis were seen. Both of transbronchial lung biopsy (TBLB) and skin biopsy also revealed non-caseating histiocytic granulomas. Oral administration of prednisolone, 40 mg/day, improved the level of serum creatinine and lysozyme. Sarcoidosis is a granulomatous disease of unknown etiology that may involve any organ or tissue of the body. The clinical picture dominating in adults is the one with pulmonary and mediastinal lymph node involvement, eye and skin lesions. Although the renal involvement were rarely encountered, the present case showed that the renal failure was one of the most important clinical feature in patient with sarcoidosis.