Snapshot A 70-year-old man presents from his nursing home for an armpit rash. He reports itchiness and some irritation with movement. His medical history includes obesity, diabetes, hypertension, hyperlipidemia, and rheumatoid arthritis. He is currently taking immunosuppressive drugs for his rheumatoid arthritis. Physical exam reveals a 5-cm erythematous plaque with peripheral scales. There are multiple satellite lesions. A skin scraping KOH preparation reveals septated hyphae. He is given topical therapy for his rash. Introduction Clinical definition login to view 2 more bullets Associated conditions login to view 3 more bullets Epidemiology Demographics login to view 3 more bullets Location login to view 1 more bullet Risk factors login to view 6 more bullets Etiology Pathogenesis login to view 6 more bullets Candida spp. login to view 4 more bullets Presentation Symptoms login to view 3 more bullets Physical exam login to view 10 more bullets Studies KOH preparation login to view 2 more bullets Trypan blue stain login to view 1 more bullet Fungal culture login to view 3 more bullets Making the diagnosis login to view 2 more bullets Differential Tinea cruris Atopic dermatitis Erythrasma Treatment Conservative login to view 3 more bullets Medical login to view 21 more bullets Complications Secondary bacterial infection