What Causes Swollen Ankle And Stiff Knees With Elevated ESR And CRP?

I had knee effusion and swelling on ankle with stiff knees and elbows and it use to worsen with fever but since I took indocap there is very much improvement just ankle swelling is left it been a week I took it . does it mean I have some kind of arthritis ? My age is 18yrs all report normal just high ESR and crp its ESR -55 .....crp56.2