Typical appearance of calcium milk gallbladder also known as limy bile.

It should be reminded that, in patients with renal insufficiency, intravenously administered contrast media are often excreted through the biliary system and may get stuck in the gallbladder for a while; known as vicarious excretion of the contrast. In this case, no intravenous contrast media had been given recently. As such, calcium milk is the most probable diagnosis.