Onychomycosis (Tinea Unguium) By Chris G. Adigun, MD, Board-Certified Dermatologist, Dermatology & Laser Center of Chapel Hill CLICK HERE FOR Patient Education NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version Nail Disorders Overview of Nail Disorders Nail Deformities and Dystrophies Onychomycosis Acute Paronychia Chronic Paronychia Ingrown Toenail Overview of Nail Disorders.) Tinea pedis psoriasis) Peripheral vascular disease or diabetes onycholysis) psoriasis or lichen planus is important because the therapies differ, so diagnosis is typically confirmed by microscopic examination and, unless microscopic findings are conclusive, culture of scrapings or rarely PCR of clippings. Scrapings are taken from the most proximal position that can be accessed on the affected nail and are examined for hyphae on potassium hydroxide wet mount and cultured. Histopathologic examination of periodic acid-Schiff (PAS)–stained nail clippings and subungual debris may also be helpful. cellulitis Diabetes or other risk factors for cellulitis (1–4). (5,6). Topical antifungal nail lacquer containing ciclopirox 8% or amorolfine 5% (not available in the US) is occasionally effective as primary treatment (cure rate of about 30%) and can improve cure rate when used as an adjunct with oral drugs, particularly in resistant infections. To limit relapse, the patient should trim nails short, dry feet after bathing, wear absorbent socks, and use antifungal foot powder. Old shoes may harbor a high density of spores and, if possible, should not be worn.