Cattleya with black on stem casing
 

I have a new compact cattleya and it has this dark casing on the stem. Is this a disease? Would love some help with this. Picture attached. - minigrower

I think what you have is normal - No worries.
These discolorations can typically occur with these sheaths in my experience. While some Cats may give empty sheaths, this is also normal. Wait it out.

that's the dead sheath and sheathy material on the pbulb - I don't think it's cause for concern :)

You can pull it off (gently) if you want to, sometimes if you leave old stem casings on, water gets into them and can cause rot.

Cattleya with black on stem casing
 

Thanks so much for your answers. I will try to remove the black casing I think. It looks so much like rot or decay.
Minigrower

I always take all the sheathing off on my pseudobulbs as soon as they begin to dry a little. Leaving them on just leaves places for critters to hide. when I am making rounds in the greenhouse I take a bucket with me and pull the old sheaths off around the pseudobulbs. However, don't take off dried up flower sheaths unless they have already bloomed. Many plants will put out an inflorenscens from old dried up flower sheaths, sometimes up to a year after they have dried. Betty

Often when leaves die they can get kind of nasty looking. If the bulbs are firm I think there's nothing to worry about. They may just be getting more sun as the days get longer and the sun gets stronger. If they're getting soft, cut them away from the plant and dust the cut with cinnamon. Make sure you cut away all the soft tissue from the rhyzome.