Having tonsilitis, caused guttate psoriasis. Rash in groin area. Solution?

hi im 22 male and have tonsilitis many years now its only got very bad the last 12 months and it caused me to get guttate psoraisis and also a rash is covering my whole groin area and my testicles i have went to my gp many times and they have given me cream for the rash but it just wont go away i ve been dealing with a rash on my groin for the last 12 months and it really is wearing me down i am due to get my tonsils out in a few days and am just wondering if the rash will clear up when i get them out????/ any reply would be massively helpful and i would appreciate it so much...thank you.