Tinea Incognito in Korea and Its Risk Factors: Nine-Year Multicenter Survey

Abstract

Tinea incognito (TI) is a dermatophytic infection which has lost its typical clinical appearance because of improper use of steroids or calcineurin inhibitors. The incidence of TI is increasing nowadays. We conducted retrospective review on 283 patients with TI from 25 dermatology training hospitals in Korea from 2002-2010 to investigate the demographical, clinical, and mycological characteristics of TI, and to determine the associated risk factors. More than half (59.3%) patients were previously treated by non-dermatologists or self-treated. The mean duration of TI was 15.0 ± 25.3 months. The most common clinical manifestations were eczema-like lesion, psoriasis-like, and lupus erythematosus-like lesion. The trunk and face were frequently involved, and 91 patients (32.2%) also had coexisting fungal infections. Among 67 isolated strains, Trichophyton rubrum was the most frequently detected (73.1%). This is the largest study of TI reported to date and the first investigational report concerning TI in Korea. We suggest that doctors should consider TI when a patient has intractable eczema-like lesions accompanied by tinea pedis/unguium. Furthermore, there should be a policy change, which would make over-the-counter high-potency topical steroids less accessible in some countries, including Korea.

A tinea incognito case report

“…Dermatitis, impetigo, urticaria, folliculitis, intertrigo, lichen simplex chronicus (LSK) and vitiligo like appearances were also found, though less frequently. while the lesions were found to be most frequently on the face and torso, 91% of the patients were also found to have comorbid fungal infection (9).…”

Acral manifestations of fungal infections

“…Mycologic confirmation with laboratory testing such as skin biopsy with PAS stain, KOH test and fungal culture is recommended before antifungal therapy. 60,61 Systemic antifungals such as terbinafine, itraconazole and fluconazole are preferred and the patients should be warned regarding the discontinuation of steroids. 62,63…”

“…60,61 The prolonged use of these drugs can cause tinea incognito because of the rapid proliferation of fungal organisms. Characteristic clinical findings are often not observed 62,63 ; therefore, it may resemble various skin conditions such as psoriasis, pyoderma and contact dermatitis in cases of involvement of the hands and feet.…”

Small pustules (pin-sized) distributed on the lateral aspects of the face

“…Pustular psoriasis-like tinea incognito (TI). The TI is a dermatophytic infection in which topical or systemic steroids have modified the clinical appearance of the mycosis, mimicking other skin diseases [4]. …”