ALG Head of Education Michelle Weddell looks at the common problem of Athlete’s foot.
Tinea Pedis, or Athlete’s foot as it is more commonly known, is the most common infection seen in adult feet. Research studies indicate the incidence is 3-51% but in the general population it is 16%. The condition is rarely seen in children
Who in your practice is likely to be affected by Tinea pedis?
The incidence in males is higher than females and if there is an underlying medical condition like Diabetes or Peripheral Vascular Disease then the incidence increases. A 60% prevalence is seen with increasing age and in the elderly. An increased incidence has been associated with obesity, families, and smoking.
What causes it?
Tinea pedis is caused by a fungus (dermatophytes) in 90% of cases. This fungus grows on or in the top layer of the skin. The most common occurring dermatophyte seen is Trichophyten Rubrum, but it could also be Trichophyton Metagropytes or Epidermphyten Flocosum.
What are the risk factors?
Drying feet with a towel allows skin scales to be shed and these can easily be transferred to the feet of healthy individuals walking barefoot on carpets or floors.
Animal fur can contain fungal spores – horses, cats and dogs are the most common causes.
Walking barefoot in the shower at the gym or around a swimming pool can increase the chance of getting the condition. Playing sport, hot weather, occlusive footwear and hyperhidrosis can also increase the incidence.
How it appears
Interdigital – this is the most common. It occurs in the webbing between the toes and causes white, cracked and macerated skin. Cracking can occur which can lead to cellulitis especially in the elderly and those with diabetes and vascular. A course of antibiotics and anti-fungal treatment may be needed to get rid of it.
Moccasin – this can look like to scaling over the sides and plantar surface of the feet or dry powdery skin in the skin creases.
Vesicobullous – Inflammation can cause intense itchiness on the sides of the feet.
What may present the same as Athlete’s foot?
Eczema / Dermatitis
Plantar pustular psoriasis
Gram negative bacterial infection
How do I identify an infection?
Diagnostic tests are not usually required, but sampling is necessary if you are unclear of your diagnosis or if the infection is not responding to topical treatments. You may want to consider referring to a dermatologist or offering oral anti-fungal treatments.
Small skin scrapings may be required as a sample for testing for microscopy and culture. It is important to keep samples at room temperature, keep in a folded piece of cardboard and to state any treatments previously tried, whether there has been animal contact or overseas travel. In clinic microscopy is useful to identify fungal hyphae.
What advice can you give patients?
- Some of the best topical treatments are: Terbinafine – Lamisil, Ketaconazole – Daktarin, Undecenoic – Mycota or Clotrimazole 1% – Canestan Antifungal (AF). Tea tree oil is not recommended but be aware that if patients have been treating the area themselves with tea tree oil then their skin may appear burnt or have developed eczema.
- It is a good idea for patients to treat the insides of all their footwear with a powder or spray.
- Following the use of topical treatments, patients should change from occlusive to leather footwear and wear natural products to keep their feet cool and dry. Footwear should be rotated and left 24 hours between use.
- Tights and socks should be made from natural cotton fibres rather than nylon and any worn pre-infections should be replaced.
- Feet must be dried thoroughly following swimming and bathing. Avoid walking barefoot and sharing towels. Avoid scratching the area which can transfer the infection to other body areas.
- Patients may have fungal infections in other areas of the body such as nails, hands and groin. Make sure that these areas are also treated to stop the re-occurrence of the condition.
References on Ivan Bristow – Podiatry Now August 2004, Journal based CPD inserts online accessed 10.09.15 www.scpod.org/_resources/assets/attachment/full/0/1101.pdf
CSK / Nice 2014 guidelines on Tinea Pedis online accessed 10.09.15 cks.nice.org/fungal-skin-infection-foot#!diagnosis