Quiz: Biofilm and Diabetic Foot Ulcers

A 47-year-old man presents with a 0.5 × 2.0 × 0.3 cm diabetic foot ulcer on his left foot beneath his first metatarsal phalangeal joint. The patient reports a medical history of type 2 diabetes, diabetic peripheral polyneuropathy, peripheral vascular disease, chronic kidney disease, eczema, and asthma. The ulcer has been present for 3 weeks.

The patient has been applying an over-the-counter triple antibiotic ointment and covering the ulcer with a nonadherent gauze dressing. He reports that the ulcer did not appear to be healing, and instead seems to have grown larger. There is no pain, erythema, edema, or odor.