Oliguric acute renal failure in mycosis fungoides with lymphomatous infiltrates in the kidneys

Objective: To present the clinical picture of acute renal failure in patients with mycosis fungoides (MF) and renal lymphomatous infiltrates. To analyze the pathogenesis of renal failure. Methods: Correlation of clinical picture, urinary findings, imaging reports and autopsy findings in two patients with long-standing MF who died with renal failure. Case summaries: Both subjects had sustained oliguria in the last 2 weeks. One patient had persistent hypotension, normal urinalysis, normal renal sonogram, and scarce interstitial lymphomatous infiltrates with preservation of renal parenchymal architecture. He was thought to have ischemic acute renal failure not directly linked to the lymphomatous infiltrates. The second patient developed hypertension one month prior to death, and had moderate proteinuria, hematuria, pyuria, grossly enlarged kidneys with hypoechoic masses, and extensive replacement of the renal parenchyma by lymphomatous infiltrates. This picture is typical of renal failure secondary to lymphomatous replacement of the kidneys. Conclusions: The development of oliguric renal failure in MF with renal lymphomatous infiltrates may have varying clinical and imaging manifestations and pathogeneses. Potentially reversible pathogenic mechanisms should be systematically investigated, particularly if the overall clinical picture is not characteristic of renal failure secondary to lymphomatous replacement of the parenchyma.