What Causes Itching And Inflammation Of Flaky Skin On Groin And Anus?

Hello doctor...I have been suffering from some skin infection in my anus area and groin area. I have seen a dermatologist and used anti biotics and clobeta-GM cream. It temporarily comes down but the itching, burning and skin patches comes back. I tried many things and now I am seeing some etrophy as well. I am worried now, please suggest best way to eliminate skin infection like inverse psoriasis, eczema like that. Thank you