Tinea cruris is a dermatophyte infection of the groin. Diagnosis is based on clinical appearance and by potassium hydroxide (KOH) wet mount. Treatment is with topical antifungals.
Tinea cruris is a dermatophytosis that is commonly caused by Trichophyton rubrum or Trichophyton mentagrophytes.
The primary risk factors are associated with a moist environment (eg, warm weather, wet and restrictive clothing, obesity causing constant friction between skinfolds). Men are affected more than women because of apposition of the scrotum and thigh.
Typically, a pruritic, ringed lesion extends from the crural fold over the adjacent upper inner thigh. Infection may be bilateral. Lesions may be complicated by maceration, miliaria, secondary bacterial or candidal infection, and reactions to treatment. In addition, scratch dermatitis and lichenification can occur.
Recurrence is common because fungi may repeatedly infect susceptible people or people with onychomycosis or tinea pedis, which can serve as a dermatophyte reservoir. Flare-ups occur more often during summer.
This photo shows a ringed lesion extending between the scrotum and upper inner thigh, resulting from a dermatophyte infection.
Diagnosis of Tinea Cruris
Primarily physical examination
Potassium hydroxide wet mount
Scrotal involvement is usually absent or slight; by contrast, the scrotum is often inflamed in candidal intertrigo or lichen simplex chronicus.
If the appearance is not diagnostic, a potassium hydroxide wet mount is helpful.
Differential diagnosis of tinea cruris includes:
Treatment of Tinea Cruris
Topical antifungal cream, lotion, or gel
(See table Options for Treatment of Superficial Fungal Infections.)
Topical antifungal options include miconazole, terbinafine, clotrimazole, ketoconazole, econazole, ciclopirox, and naftifine. Topical antifungal options include miconazole, terbinafine, clotrimazole, ketoconazole, econazole, ciclopirox, and naftifine.
Oral antifungal agents such as itraconazole (Oral antifungal agents such as itraconazole (1), terbinafine, or sometimes both for 3 to 6 weeks may be needed in patients who have refractory, inflammatory, or widespread infection (), terbinafine, or sometimes both for 3 to 6 weeks may be needed in patients who have refractory, inflammatory, or widespread infection (1, 2).
Treatment references
1. Khurana A, Agarwal A, Agrawal D, et al. Effect of Different Itraconazole Dosing Regimens on Cure Rates, Treatment Duration, Safety, and Relapse Rates in Adult Patients With Tinea Corporis/Cruris: A Randomized Clinical Trial. . Effect of Different Itraconazole Dosing Regimens on Cure Rates, Treatment Duration, Safety, and Relapse Rates in Adult Patients With Tinea Corporis/Cruris: A Randomized Clinical Trial.JAMA Dermatol. Published online September 14, 2022. doi:10.1001/jamadermatol.2022.3745
2. Hassaan ZRAA, Mohamed HAK, Eldahshan RM, et al. Comparison between the efficacy of terbinafine and itraconazole orally vs. the combination of the two drugs in treating recalcitrant dermatophytosis. . Comparison between the efficacy of terbinafine and itraconazole orally vs. the combination of the two drugs in treating recalcitrant dermatophytosis.Sci Rep. 2023;13(1):19037. Published 2023 Nov 3. doi:10.1038/s41598-023-46361-z
Key Points
Suspect tinea cruris when pruritic, ringed lesions extend from the crural fold to the adjacent upper inner thigh, particularly in patients with obesity or in men.
Topical terbinafine, miconazole, clotrimazole, ketoconazole, econazole, ciclopirox, or naftifine 2 times a day for 10 to 14 days is usually effective.Topical terbinafine, miconazole, clotrimazole, ketoconazole, econazole, ciclopirox, or naftifine 2 times a day for 10 to 14 days is usually effective.
In severe or refractory cases, oral itraconazole and terbinafine may be used. In severe or refractory cases, oral itraconazole and terbinafine may be used.
Drugs Mentioned In This Article
