A sonogram of the right kidney typically demonstrates which of the following abnormalities?

In a sonogram of the right kidney, sinus lipomatosis is a condition characterized by the accumulation of fat in the renal sinus. This can often be visualized on ultrasound as an increased echogenicity in the renal sinus area and a possible widening of the renal sinus itself. It is typically associated with aging and is not a sign of disease but rather a benign condition, which can present as an incidental finding during a kidney ultrasound.

In contrast, other conditions like glomerulonephritis, chronic renal failure, and acute tubular necrosis would typically present with different ultrasound features. For instance, glomerulonephritis might show changes in kidney size and echogenicity due to inflammation. Chronic renal failure may lead to reduced kidney size and increased echogenicity due to scarring, while acute tubular necrosis often presents with enlarged kidneys and increased echogenicity due to interstitial edema and changes in the renal parenchyma.

The distinct visualization of sinus lipomatosis in ultrasound as an accumulation of fat differentiates it from the more pathologic features associated with the other listed conditions, making it a correct choice when discussing typical sonographic findings of the right kidney.