Hi,
First of all, I wish you safe and quick recovery. I remembered someone before asked about the same question. The conclusion is not. You will not be denied access because of Psoraisis.
This disease is:
1- Not contagious
2- won't require any heavy social care or would be a burden on the system.
These are the two criteria the visa officer uses to evaluate any medical diseases.
Even though, if we hypothetically assume that the VO might have an issue on this, they most likely grant an entry/visa with medical furtherance, which requires immigrants to check regularly with a DMP to monitor and control the case. We've seen examples on this in the forum.
I recommend you go ahead and don't think twice.
Good luck,