Granulomatous intersticial nephritis secondary to sarcoidosis

ABSTRACT Introduction: Granulomatous interstitial nephritis is a rare condition, in which renal involvement is uncommon. Its etiology is variable, and may be medicinal, infectious or inflammatory origin. Case report: This is a 65-year-old male patient with renal lesions of unknown etiology, associated with hypercalcaemia. During the investigation, cardiac insufficiency with diastolic dysfunction and interstitial lung involvement on chest tomography were evidenced. Renal function (glomerular filtration rate) has partially improved with clinical measures. Renal biopsy was performed, which showed moderate interstitial lesion with tuberculoid granulomas without caseous necrosis. Conclusion: The objective of the article was to describe a case of NIG and to alert to the importance of its clinical investigation. In this case, renal biopsy, associated with systemic clinical manifestations, contributed to the diagnosis of sarcoidosis.

摘要
引言：肉芽肿性间质性肾炎（Granulomatous interstitial nephritis，以下简称NIG）是一种罕见疾病，肾脏受累并不常见。其病因复杂多变，可分为药物源性、感染源性或炎症源性。
病例报告：本例为一名65岁男性患者，罹患病因不明的肾脏病变，伴随高钙血症。检查过程中，经胸部CT（chest tomography）证实患者存在舒张功能不全性心功能不全及间质性肺受累。经临床干预后，患者肾功能指标（肾小球滤过率（glomerular filtration rate））已部分改善。随后实施肾活检（renal biopsy），结果显示存在中度间质性病变，伴类结核样肉芽肿，未见干酪样坏死（caseous necrosis）。
结论：本文旨在报道1例肉芽肿性间质性肾炎（NIG）病例，并提醒临床需重视此类疾病的系统排查工作。本例中，结合全身临床表现开展肾活检，最终明确了结节病（sarcoidosis）的诊断。