Department of Nephrology, Hospital Universitario Clínico San Carlos, Madrid, Spain.
Department of Pathology, Hospital Universitario Doce de Octubre, Madrid, Spain.
Am J Kidney Dis. 2022 Jul;80(1):147-150. doi: 10.1053/j.ajkd.2021.08.013. Epub 2021 Sep 25.
Metastatic disease in the kidney is relatively uncommon compared to other body sites. In most cases it presents as a unilateral and unifocal mass in the tubulointerstitial region. Intraglomerular metastases are even rarer, and their diagnosis is hampered by the limitations of imaging techniques in detecting them. We describe the finding of intraglomerular metastases in a patient affected by a malignant melanoma considered to be in partial remission, with no evidence of melanoma progression on the previously performed computed tomography scan. This patient developed rapidly progressive kidney failure, proteinuria, and hematuria with dysmorphic red blood cells in the urine sediment. Kidney biopsy showed a marked crescentic proliferation caused by tumor cells, which even invaded the proximal convoluted tubule. Melanoma cells were also found in the lumina of the glomerular capillaries, distending their basement membranes. Our case describes the histologic and electron microscopic findings of this form of intraglomerular metastasis and reminds us of its inclusion in the differential diagnosis of rapidly progressive kidney failure.
与其他部位相比，肾脏的转移性疾病相对少见。大多数情况下，它表现为肾间质区的单侧、单发肿块。肾小球内转移更为罕见，其诊断受到成像技术在检测它们方面的限制。我们描述了一例恶性黑色素瘤患者的肾小球内转移发现，该患者被认为处于部分缓解期，之前进行的计算机断层扫描没有黑色素瘤进展的证据。该患者迅速出现进行性肾衰竭、蛋白尿和血尿，尿沉渣中出现形态异常的红细胞。肾活检显示由肿瘤细胞引起的明显新月体性增殖，甚至侵犯近端曲管。肾小球毛细血管腔内也发现了黑色素瘤细胞，使其基底膜扩张。我们的病例描述了这种形式的肾小球内转移的组织学和电子显微镜发现，并提醒我们将其纳入快速进行性肾衰竭的鉴别诊断。
