What is the diagnosis and treatment for Tinea (Ringworm)?

From the Guidelines

Ringworm, also known as tinea capitis, should be treated with oral therapy, as topical therapy alone is not recommended, and the choice of systemic therapy should be directed by the causative dermatophyte and/or local epidemiology. The treatment of ringworm typically involves the use of antifungal medications, with griseofulvin and terbinafine being the most widely used first-line treatments 1.

• Griseofulvin is more effective against Microsporum species, while terbinafine is more efficacious against Trichophyton species.
• The dosage of griseofulvin is 15-20 mg/kg per day for 6-8 weeks for children weighing less than 50 kg, and 1 g per day for 6-8 weeks for children weighing more than 50 kg 1.
• The dosage of terbinafine is 625 mg per day for 2-4 weeks for children weighing less than 20 kg, 125 mg per day for 2-4 weeks for children weighing 20-40 kg, and 250 mg per day for 2-4 weeks for children weighing more than 40 kg 1. It is essential to note that treatment failure may occur due to lack of compliance, suboptimal absorption of the drug, relative insensitivity of the organism, or reinfection, and in such cases, second-line therapy with itraconazole may be considered 1.
• Itraconazole is safe and effective, with activity against both Trichophyton and Microsporum species, and can be used at a dosage of 50-100 mg per day for 4 weeks, or 5 mg/kg per day for 2-4 weeks 1. In addition to antifungal medication, it is crucial to maintain good hygiene practices, such as keeping the affected area clean and dry, avoiding sharing personal items, and washing bedding and clothes in hot water to prevent reinfection or spreading to others.
• Children receiving appropriate therapy should be allowed to attend school or nursery, and index cases due to T. tonsurans warrant screening of all family members and close contacts and treatment for those positive cases 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Accurate diagnosis of the infecting organism is essential. Identification should be made either by direct microscopic examination of a mounting of infected tissue in a solution of potassium hydroxide or by culture on an appropriate medium Medication must be continued until the infecting organism is completely eradicated as indicated by appropriate clinical or laboratory examination. Representative treatment periods are tinea capitis, 4 to 6 weeks; tinea corporis, 2 to 4 weeks; tinea pedis, 4 to 8 weeks; INDICATIONS AND USAGE Griseofulvin oral suspension, USP is indicated for the treatment of dermatophyte infections of the skin not adequately treated by topical therapy, hair and nails, namely: Tinea corporis Tinea pedis Tinea cruris Tinea barbae Tinea capitis Tinea unguium when caused by one or more of the following species of fungi: Ringworm is also known as Tinea.

• The treatment for Tinea corporis (ringworm of the body) with griseofulvin is 2 to 4 weeks 2.
• The diagnosis should be confirmed by laboratory testing, such as KOH preparation or fungal culture 2.
• Griseofulvin is indicated for the treatment of dermatophyte infections, including Tinea corporis 2.

From the Research

Definition and Prevalence of Ringworm

• Ringworm, also known as tinea corporis, is a fungal infection of the skin caused by dermatophytes 3.
• It is estimated that 10% to 20% of the world population is affected by fungal skin infections, including ringworm 3.

Symptoms and Diagnosis

• Ringworm typically presents as a well-demarcated, sharply circumscribed, oval or circular, mildly erythematous, scaly patch or plaque with a raised leading edge 4.
• Mild pruritus is common, and the diagnosis is often clinical but can be difficult with prior use of medications, such as calcineurin inhibitors or corticosteroids 4.
• Dermoscopy is a useful and non-invasive diagnostic tool, and the diagnosis can be confirmed by microscopic examination of potassium hydroxide wet-mount preparations of skin scrapings from the active border of the lesion 4.

Treatment Options

• The standard treatment of ringworm is with topical antifungals, and systemic antifungal treatment is indicated if the lesion is multiple, extensive, deep, recurrent, chronic, or unresponsive to topical antifungal treatment 4.
• Terbinafine and naftifine are effective treatments for ringworm, with significantly higher clinical cure rates compared to placebo 3.
• Itraconazole is also an effective treatment, with a higher cure rate compared to fluconazole, griseofulvin, and terbinafine in some studies 5.
• Griseofulvin and terbinafine are effective in the treatment of tinea imbricata, a type of ringworm 6.

Efficacy of Antifungal Agents

• The efficacy of antifungal agents against dermatophytes can vary, with itraconazole and terbinafine showing the lowest MIC values in some studies 7.
• Fluconazole has been shown to have limited effectiveness in the treatment of ringworm, with a lower cure rate compared to itraconazole and terbinafine in some studies 5.
• The choice of antifungal agent depends on various factors, including the extent of involvement, social situation, and availability of resources such as laboratory testing and follow-up 6.