What is Tinea pedis and Onychomycosis?
Tinea pedis is an inflammatory condition and characterises the most prevalent of all the superficial fungal skin infections. Trichophyton rubrum, a hugely specialised dermatophyte is by far the most common cause of fungal foot infection (FFI) which has evolved to residing within the human epidermis.
When the disorder is established on the foot, the infection may also extend to the toenails causing oychomycosis. Dermatophytes typically spread under the free edge of the nail. A nail infection is almost always a secondary event to skin infection.
The symptoms associated with Tinea pedis and onychomycosis include:
- Tinea pedis is classically reported as an acute, itchy infection accompanied by erythema or as inter-digital fissuring and maceration. Although in practice due to its subtle appearance, T rubum may produce few symptoms other than dry skin from which itching is often absent.
- Discolouration of the nail to white, yellow or black
- Thickening of the nail
- Discolouration of the nail bed to yellow or white
- Foul smell
- Total nail dystrophy – occurs when the infection proceeds to affect the whole nail
- White superficial onychomycosis
What can I do to treat Tinea pedis and onychomycosis?
For most FFI, simple measures are the most successful at treating the disease. A range of topical medicaments are used for established skin infections, there are three main groups:
- Allylamines – terbinafne
- Imidazoles – clotrimazole, ketoconazole, sulconazole, miconazole
- Morpholine derivatives – amorolfine
Allylamines and imidazoles have demonstrated to be more effective when treating any fungal skin infection of the foot. Most topical therapies require a weeks course of treatment.
- Fungal infections of the nails presents a significant challenge. Topical agents alone are only designated when the lunula of the affected nail is free from symptoms. Tioconazole paint and amorolfine lacquer are available medicants, but when taking these alone could take up to 12 months for complete resolution with no immediate noticeable results.
- Where the fungal infection can be seen spreading proximally into the lunula (half moon) a systemic agent is required. The main oral agents are terbinafine and itraconazole. Combining an oral antifungal agent with a topical nail lacquer has revealed to be more effective than using an oral agent alone. Thickened mycotic nails reduces the chances of success, therefore reduction of the nails before treatment can enhance the likelihood of success.
What is the likelihood of fungal foot infection returning?
- Avoidance of patient obtaining new infection can be managed following basic advice, for example, keeping nails short, checking feet regularly, ensuring feet are kept dry, as well as avoiding walking barefoot in damp areas such as public swimming pools and sports facilities.
- Re-infection may also occur from hosiery and footwear. Where possible, old socks and shoes should be disposed when a cure has been successful to reduce the chances of reinfection.