Snapshot A 50-year-old man presents with a rash on his right foot. He reports noticing this rash between his fourth and fifth toe a few days ago, and denies any symptoms related to the rash. He has a past medical history of diabetes managed with metformin, and obesity. He lives in Chicago, where it is currently summer and very humid. On physical exam, there is a erythematous and macerated scaly plaque between his fourth and fifth toe. He is given topical antibiotics for management of this disease. Introduction Clinical definition login to view 2 more bullets Associated conditions login to view 2 more bullets Epidemiology Demographics login to view 2 more bullets Risk factors login to view 5 more bullets Etiology Infection by gram-positive bacillus, C. minutissimum Pathogenesis login to view 2 more bullets Presentation Symptoms login to view 1 more bullet Physical exam login to view 9 more bullets Studies Wood’s lamp examination login to view 1 more bullet Gram stain of skin scraping login to view 1 more bullet KOH preparation login to view 1 more bullet Diagnostic criteria login to view 2 more bullets Differential Seborrheic dermatitis login to view 2 more bullets Tinea versicolor login to view 1 more bullet Treatment Medical login to view 14 more bullets Complications Secondary bacterial infection