Also diabetes leads peripheral neuropathy, atherosclerosis etc which make wound healing troublesome. You need a culture sensitivity of wound scraping to know what
antibiotics will suit the infection. If there is underlying dermatitis, then this needs to be taken care of. If there is severe atherosclerosis preventing blood supply to wound, then this needs to be diagnosed by angiograms. Wound debridement would be required along with proper dressing at a wound clinic.