I have been seeing a rheumatologist for about a year for varying symptoms and today I have been diagnosed .....

[Alex97]

by a dermatologist as having nail psoriasis. I don't have it anywhere else. my question is will it spread from my nails to my skin?

[earthwitch]

If you have confirmed dermatitis and also arthritis symptoms, then you could have psoriatic arthritis. Your rheumatologist will be likely to try you on disease modifying drugs (DMARDs) that deal with both the psoriasis and the arthritis as they are likely linked, so if your treatment works, then I would expect that the psoriasis won't get any worse and may even clear up.