What is the most likely diagnosis for a cat with choleostasis, liver failure, and operculated eggs in feces?

The presence of operculated eggs in the feces along with symptoms of cholestasis and liver failure strongly indicates an infection caused by Platynosomum fastosum, commonly known as the cat liver fluke. These flukes are parasitic flatworms that primarily affect the liver and biliary system in cats, leading to cholestasis, which is a condition characterized by the accumulation of bile due to bile flow obstruction.

Choleostasis can result from the fluke's migration and presence in the bile ducts, causing inflammation and damage to liver tissues, ultimately leading to liver failure. The operculated eggs in the feces are a distinguishing characteristic of Platynosomum fastosum, as they are released into the environment through the feces.

Other options, while relevant to parasitic infections in cats, do not align with the specific combination of symptoms and egg types observed in this scenario. For instance, Cystoisospora felis is a protozoan that typically causes gastroenteritis rather than liver disease, Dipylidium caninum is a tapeworm primarily leading to gastrointestinal issues, and Ascaris suum is more relevant to pigs and is not typically associated with liver disease in cats. Hence, the comprehensive evidence