• Medullary nephrocalcinosis: Hyperechogenicity with shadowing on sonography is a hallmark of calcification. Areas of diffuse calcification that appear triangular in shape and are arranged radially along the renal sinus are calcified renal pyramids. Diffusely calcified renal pyramids are a manifestation of medullary nephrocalcinosis.

• Multiple renal stones: Stones appear as densely echogenic structures with distal acoustic shadowing. When they are located in renal calices, they may superficially resemble calcified pyramids. However, when multiple, they vary in shape and size and are unlikely to be present in all calices. A dilated collecting system may be seen.