Presentation
Small echogenic nodule in the left kidney.
Patient Data
The CT scan shows that the ultrasound finding (no images available) corresponds to a small lipid content nodule in the left kidney.
Case Discussion
Renal angiomyolipomas are benign renal neoplasm composed of vascular, smooth muscle and fat elements. Angiomyolipomas are often found incidentally when the kidneys are imaged for other reasons, such in this case (ultrasound). Most lesions involve the cortex and demonstrate macroscopic fat (< - 20HU). When small, volume averaging may make differentiation from a small cyst difficult. It is important to realize that a proportion of angiomyolipomas are fat-poor.
Calcification is rare.
The diagnosis can be confirmed by imaging characteristics as such in this case.