Faculty Bibliography

Tinea corporis and tinea cruris are common dermatophyte infections of increasing public health concern, yet national U.S. data are limited. We estimated incidence, risk factors, diagnostic and treatment practices among a large Medicaid-insured outpatient cohort. Among ∼6 800 000 enrollees, 54 108 were diagnosed with tinea corporis (79.1/10 000 person-years) and 8 386 with tinea cruris (12.2/10 000 person-years). Tinea corporis primarily affected young children and Black patients, while tinea cruris was prevalent among middle-aged men. Overall, less than 10% received diagnostic testing, and 7-10% were treated with combination antifungal-corticosteroid products, highlighting the opportunities to increase testing and promote judicious antifungal use amid emerging resistance.

Sporotrichosis is an implantation mycosis caused by Sporothrix species. The global burden of disease is largely unknown, as routine surveillance is not conducted in most countries. The increasing disease burden paired with emerging zoonotic transmission highlight the growing public health significance of sporotrichosis. In this article, we describe the epidemiology and outline an approach to the diagnosis and treatment of sporotrichosis.

Tinea infections (often called ringworm) are caused by dermatophyte fungi and classified by the body site involved. Tinea corporis and tinea capitis are most common in prepubertal children, and tinea cruris, tinea pedis, and tinea unguium (most common type of onychomycosis) are more likely in adolescents and adults. Clinical diagnosis without testing may be unreliable because other conditions can resemble tinea infections (eg, tinea corporis can be confused with eczema, and onychomycosis with dystrophic toenails from repeated low-level trauma or psoriasis). Tinea corporis, tinea cruris, and tinea pedis generally respond to inexpensive topical antifungal agents, but oral antifungal agents may be indicated for patients with extensive disease, lack of response to topical treatment, immunocompromise, or hair follicle involvement (eg, tinea capitis). Oral terbinafine is considered first-line therapy for tinea capitis and onychomycosis because it is well tolerated, effective, and inexpensive. Emerging tinea infections may be more severe than classic tinea infections and generally do not improve with first-line topical or oral antifungals. These infections may require prolonged oral antifungal therapy and specialized diagnostic testing. Antifungal stewardship, including avoiding the use of combination antifungal-corticosteroids, should be emphasized to optimize outcomes and help prevent resistance.