Approach to the treatment of tinea pedis, tinea corporis, and tinea cruris

KOH: potassium hydroxide.
* Diagnostic accuracy of a KOH preparation is influenced by factors such as clinician experience and collection of an adequate specimen.
¶ The recognition of classic physical findings supports high confidence in the clinical diagnosis. Refer to UpToDate topics on dermatophyte (tinea) infections for classic clinical findings.
Δ Localized infection may be considered infection limited to a single body area (eg, feet) or limited skin involvement for which topical application would be feasible.
◊ Fungal culture is an alternative method of confirming fungal infection; however, results may not be available for a few weeks. The differential diagnosis determines the need for skin biopsy or other diagnostic tests.
§ A trial of antifungal therapy may be reasonable for patients with limited skin involvement while awaiting other diagnostic tests or referral. Patients given a trial of topical antifungal therapy should be reassessed for improvement within a few weeks.
¥ Topical therapy with antifungal agents such as azoles, allylamines, butenafine, ciclopirox, tolnaftate, or amorolfine is effective. Nystatin is not effective for dermatophyte infections.
‡ Patients who find topical therapy challenging may benefit from oral antifungal treatment.
† Emerging resistance of dermatophytes to antifungal therapies may account for some treatment failures. However, availability of susceptibility testing is limited, and the prevalence of resistance varies. Resistance appears to be infrequent in many locations but may be underestimated^[1].
** Refer to UpToDate topics on dermatophyte (tinea) infections for details on preventive measures.