Severe Acute Kidney Injury Due to Intraglomerular Melanoma: A Case Report.

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.

[Circumferential calcifications in cromophobe renal cell carcinoma: Description of a clinical case and review of the literature.] / Calcificaciones anormales en tumor renal de células cromófobas: descripción de un caso clínico y revisión de la literatura.

We present a clinical case of an asymptomatic 61-year-old man was found to have a left kidney mass. Ultrasound and CT showed a 6 x 5 cms mass with calcifications. Histologic examination of the radical nephrectomy specimen revealed a chromophobe renal cell carcinoma. The unique feature of this case is the type of calcifications present in a tumor of this category. To our knowledge, were port the first case of chromophobe renal cell carcinoma with peripheral linear calcifications. A literature review onchromophobe renal cell carcinoma with calcifications is performed.

Presentamos el caso de un varón de 61 años diagnosticado de forma incidental de una tumoración renal izquierda. Las imágenes radiológicas obtenidas mediante ecografía y TAC muestran una masa de 6 x 5 cms con calcificaciones circunferenciales y periféricas. El estudio anatomopatológico de la pieza de nefrectomía radical evidencia un carcinoma renal de células cromófobas. La peculiaridad de este caso reside en el tipo de calcificaciones presentes en un tumor de este tipo no habiéndose descrito previamente, en nuestro conocimiento, calcificaciones lineales periféricas como éstas, en carcinoma renal de células cromófobas. Realizamos una revisión de la literatura acerca de las calcificaciones en carcinoma renal de células cromófobas.

De Novo IgA Nephropathy in a Renal Allograft.

Posttransplant glomerulonephritis is a complication of kidney transplant that can impair graft function and long-term graft survival. De novo immunoglobulin A disease in kidney allografts appears to be much less common than the recurrent disease, and in most cases it is diagnosed in protocol biopsies with no clinical evidence of disease or in association with other renal transplant pathologies such as chronic rejection. We present a case of de novo immunoglobulin A nephropathy presenting with overt proteinuria, microscopic hematuria, and progressive deterioration of renal function 30 months after renal transplant.

[Laparoscopic renal cyst excision: Large simple renal cyst treatment with renal cell carcinoma cells in its wall. Histogenetic considerations and bibliographic review.] / Quistectomía laparoscópica: tratamiento de un quiste simple de gran tamaño con carcinoma de células renales en su pared. Consideraciones histogenéticas y revisión de la literatura.

OBJECTIVE: The incidence of simple renal cysts is very high, especially in elderly people. However, malignant transformation of a simple renal cyst is exceptional. Likewise, the treatment to be carried out, in these rare cases, is controversial, with respect to opting for radical renal surgery. METHODS: We present the case of a patient with a solid nodule in a large cyst. Complete removal of the cyst was performed by transperitoneal laparoscopic technique. The histopathological study of the surgical piece revealed the existence of a cyst with clear renal cell carcinoma with nucleolar grade 2. The clinical evolution has been satisfactory, performing a minimally invasive surgery (laparoscopic cyst excision). DISCUSSION: Although it is considered that surgical treatment of choice is radical surgery in these cases, we believe that nephron sparing surgery may represent a therapeutic option, taking into account the young age of our patient. A histogenetic hypothesis is discussed to explain the appearance of a clear cell tumor in a simple renal cyst. CONCLUSION: The development of a renal cell carcinoma in simple renal cysts is a very infrequent pathology.Laparoscopic total cystectomy is a minimally invasive therapeutic option for the treatment of renal cell carcinoma originating in a simple renal cyst, although it is of an important size. We establish the hypothesis of migration of the cells of the renal collecting tubes into the cyst wall to explain the malignant transformation of the renal simple cyst.

OBJETIVO: La incidencia de los quistes renales simples es muy frecuente, sobre todo en personas de edad avanzada. Sin embargo, la transformación maligna de un quiste renal simple es excepcional. Así mismo, el tratamiento a realizar, en estos casos raros, es un motivo de controversia, con respecto a optar por una cirugía radical renal.MÉTODOS: Presentamos el caso de un paciente con nódulo sólido en un quiste de gran tamaño. Se realiza extirpación completa del quiste mediante técnica de laparoscopia vía transperitoneal. El estudio histopatológico de la pieza quirúrgica revela la existencia un quiste con un carcinoma renal de células claras con grado nucleolar 2. La evolución clínica ha sido satisfactoria, realizando una cirugía de mínima invasión (quistectomía laparoscópica). DISCUSIÓN: Aunque se considera que el tratamiento quirúrgico es la cirugía radical en estos casos, nosotros consideramos que la cirugía preservadora de nefronas puede representar una opción terapéutica, teniendo en cuenta la edad de nuestro paciente. Se comenta una hipótesis histogenética para explicar la aparición de un tumor de células claras en un quiste renal simple. CONCLUSIONES: El desarrollo de un carcinoma de células renales en quistes renales simples es una patología muy infrecuente. La quistectomía total laparoscópica es una opción terapéutica mínimamente invasiva, para el tratamiento del carcinoma de células renales originado en un quiste renal simple, aunque éste sea de un tamaño importante. Proponemos la hipótesis de una migración de las células de los túbulos renales en la pared del quiste para explicar la transformación maligna del quiste simple renal.