It is Tinea Infection
- Dermatophytic infections of the skin include:
- Tinea corporis (ringworm)
- Tinea capitis (ringworm of the scalp)
- Tinea cruris (jock itch)
- Tinea pedis (athlete’s foot)
- Tinea unguium (onychomycosis)
- Tinea manuum (commonly presents with “one-hand, two-feet” involvement)
- Tinea barbae (beard infection in male adolescents and adults)
- Tinea incognito (altered appearance of dermatophyte infection caused by topical steroids)
- Pityriasis versicolor (formerly tinea versicolor) caused by Malassezia
Dermatophytes are fungi that invade and multiply within keratinized tissues (skin, hair, and nails) causing infection. Based upon their genera, dermatophytes can be classified into three groups: Trichophyton (which causes infections on skin, hair, and nails), epidermophyton (which causes infections on skin and nails), and Microsporum (which causes infections on skin and hair). Based upon mode of transmission, these have been classified as anthropophillic, zoophilic, and geophilic. Finally, based upon the affected site, these have been classified clinically into tinea capitis (head), tinea faciei (face), tinea barbae (beard), tinea corporis (body), tinea manus (hand), tinea cruris (groin), tinea pedis (foot), and tinea unguium (nail). Other clinical variants include tinea imbricata, tinea pseudoimbricata, and Majocchi granuloma.
Dermatophytes are the most common agents of superficial fungal infections worldwide and widespread in the developing countries, especially in the tropical and subtropical countries like India, where the environmental temperature and relative humidity are high. Other factors such as increased urbanization including the use of occlusive footwear and tight fashioned clothes, has been linked to higher prevalence. Over the last few years, studies on epidemiology of dermatophytic infection from different part of India have shown a rising trend in the prevalence of cutaneous dermatophytosis with change in spectrum of infection and isolation of some uncommon species.
Trichophyton rubrum continues to be the most common isolate with tinea corporis and cruris the most common clinical presentation in relatively large studies from Chennai and Rajasthan. However, in studies from Lucknow and New Delhi, Trichophyton mentagrophytes and Microsporum audouinii were the most frequent isolate. Few studies also showed isolation of rare species like Microsporum gypseum in nonendemic part of the world.
Differential diagnosis of Tinea infections
Annular psoriasis, Atopic dermatitis, Erythema multiforme, Fixed drug eruption, Granuloma annulare, Lupus erythematosus, Nummular eczema, Pityriasis rosea herald patch, Seborrheic dermatitis. All these lesions can be included in differential diagnosis of tinea corporis but significant demarcations can be done on the basis of specific characteristics of these lesions and Tinea as well.
Tinea corporis (ringworm) typically presents as a red, annular, scaly, pruritic patch with central clearing and an active border. Lesions may be single or multiple and the size generally ranges from 1 to 5 cm, but larger lesions and confluence of lesions can also occur. A potassium hydroxide (KOH) preparation is often helpful when the diagnosis is uncertain based on history and visual inspection. Worsening after empiric treatment with a topical steroid should raise the suspicion of a dermatophyte infection. Conversely, if a nonfungal lesion is treated with an antifungal cream, the lesion will likely not improve or will worsen. Cultures are usually not necessary to diagnose tinea corporis.
Patients should be encouraged to wear loose-fitting garments made of cotton or synthetic materials designed to wick moisture away from the surface. Socks should have similar properties. Areas likely to become infected should be dried completely before being covered with clothes. Patients should also be advised to avoid walking barefoot and sharing garments.
Topical antifungal therapy
For sustained cure, butenafine and terbinafine each was found to be superior to clotrimazole. Pairwise comparison of topical antifungals for the outcome of fungal cure showed butenafine and terbinafine each to be superior to clotrimazole, oxiconazole, and sertaconazole; terbinafine to be superior to ciclopirox, and naftifine to be superior to oxiconazole.
The topical antifungal treatments for tinea cruris and tinea corporis suggest that the individual treatments with terbinafine and naftifine are effective with few adverse effects. Other topical antifungals like azoles treatments are also effective in terms of clinical and mycological cure rates.
Oral antifungal therapy in Tinea corporis
Out of the various systemic antifungals, terbinafine, and itraconazole are commonly prescribed. Griseofulvin and fluconazole are also effective but require long-term treatment.