We see a wide variety of diseases affecting the skin, ears, and nails that are not so easily categorized.
Here are a few examples.

Zinc responsive dermatosis causes thick crusts to appear around the lids.

Hepatocutaneous syndrome is a skin disease that occurs secondary to severe internal disease.

This dog had burns after the tea fire in Santa Barbara.

Lamellar ichthyosis is a genetic disease that causes dramatic skin flakes.

There are a number of disease that can cause abnormal nails.