However to completely rule out fungal infection, you should get KOH examination of the
skin scrapings and fungal culture done. Also get a biopsy
skin to rule out psoriasis. Psoriasis is a long-term (chronic) skin problem that causes skin cells to grow too quickly, resulting in thick, white, silvery, or red patches of skin.It is thought that psoriasis occurs when the immune system overreacts, causing inflammation and flaking of skin.
I hope it helps. Take care and regards.