Renal replacement lipomatosis

Bilateral Renal Replacement Lipomatosis: A Case Report on Rare Complication of Obstructive Uropathy

Renal replacement lipomatosis (RRL) is an uncommon complication, leading to the fatty replacement of the renal parenchyma. Various etiologies have been described for this long-term infirmity, but obstructive uropathy is one paramount cause. Previously described reports have documented unilateral disease in the majority, but we are narrating a case of bilateral RRL, which is very scarce in the literature. A 57-year-old man, who was a known case of obstructive uropathy, presented to us with the symptoms of urinary tract infection. In imaging evaluation, the patient was found to have bilateral RRL.

Imaging findings of lipomatosis: a comprehensive review

Lipomatosis is a benign and non-encapsulated mature form of fat tissue proliferation, which can be isolated or multiple, symmetrical or infiltrative, and may be associated with several syndromes. Lipomatosis has been reported to involve almost every part and organ in the body. In this review, we present imaging findings at common locations of lipomatosis and summarize lipomatosis-related syndromes.

Allograft dysfunction in a patient with an odd-looking kidney: case of renal lipomatosis and review of literature

Renal lipomatosis was diagnosed in a kidney transplant recipient who presented with acute kidney injury (AKI) several years after transplantation. The patient had an odd-looking kidney transplant on ultrasound and computed tomography (CT) scan, showing a medullary mass with resultant compression of the surrounding renal parenchyma. A biopsy of the renal medulla confirmed fatty infiltration of the renal parenchyma. The patient underwent percutaneous nephrostomy and AKI resolved with relief of the obstruction. Renal lipomatosis is a rare condition that should be differentiated from other neoplasms of the kidney. When it occurs in a functioning transplant kidney, the treatment approach proves to be very challenging.

Renal sinus lipomatosis in transplanted kidneys: an unusual clinical case

Renal sinus lipomatosis (RSL) represents an abnormal proliferation of the adipose tissue surrounding the renal pelvis of uncertain origin, associated with aging, obesity, steroid excess, infections, and calculosis. It represents a rare complication in transplanted kidneys, and, despite the accurate and prolonged radiological followup of transplanted organs, only a few cases of RSL have been described in graft recipients, with no remarkable effects on renal function. The diagnosis relies on ultrasonography (US), magnetic resonance imaging (MRI), computed tomography (CT), and, finally, percutaneous biopsy. We describe the case of an extensive RSL in a 38-year-old renal transplant recipient, diagnosed by ultrasonography and computed tomography. The patient underwent a radiologic study because of an acute, asymptomatic renal impairment, that led to the diagnosis of a RSL of unusual dimensions, associated with a discrete hydronephrosis. Paradoxically, after a short course of steroids, the recovery of renal function and the partial resolution of calyceal dilatation were observed. The rarity of this affection, the need of a differential diagnosis with fat-containing tumors, and the possibility of parenchymal inflammation associated with RSL, potentially responsive to steroids, are also discussed.

Total renal replacement lipomatosis

Renal replacement lipomatosis can be defined as the proliferation of fibrofatty tissue which subsequently replaces the renal parenchyma. It is usually unilateral and occurs as a result of severe atrophy or destruction of the renal parenchyma, mostly due to a calculus with secondary proliferation of renal sinus, renal hilus, and perirenal fatty tissue to a variable extent. There may be moderate replacement of renal tissue by fat as in renal sinus lipomatosis or in severe cases the whole of the renal parenchyma may be replaced by fat and is referred to as renal replacement lipomatosis. Herein we report a case of total renal replacement lipomatosis. The possible pathogenic mechanisms and the treatment are also discussed.