Contents
Introduction
Tinea refers to a specific type of fungal infection, caused by dermatophyte fungus. Fungal infections are often divided into 3 different types:
- Tinea
- Caused by dermatophyte fungus
- Candida
- Caused by the candida fungus
- Pityriasis veriscolor
- Caused by the malassezia fungus
Tinea is often given different names, depending on the location of the infection – for example tinea pedis affects the feet (athletes foot) and tinea corporirs affects the limbs (also sometimes referred to as “ringworm’ due to the ring-like nature of some of the lesions it causes).
Often, multiple locations of infection exists on the same patient, most commonly transferred from the foot. The exact species of tinea vary by geographical location. Some types are caught from pets or farm animals. Probably the most common form is Tinea rubrum.
Aetiology
- Usually caught from another infected individual
- e.g. shared towels, close skin contact, walking barefoot in shared changing rooms
- Tinea pedis
- Occlusive footwear – e.g. heavy work boots
- Excessive sweating, excessive exercise
- Diabetes
- Co-existing fungal nail infection
- Use of steroids
- Immunsuppression
Presentation
- May be acute or gradual onset
- Usually itchy and inflamed
- Tinea pedis is often particularly itchy
- If widespread at presentation it can be particularly difficult to treat
- Tinea pedis
- Usually asymmetrical pattern
- Can be bilateral or unilateral
- Most commonly affects the spaces between 4th and 5th toes
- Scaly and may affect the whole of the sole of the foot
Diagnosis
- Diagnosis is usually clinical
- Skin scraping can be sent
- Typical features can be seen on microscopy – which may negate the need for culture
- Culture can take months
Differential diagnosis
Tinea pedis
Tinea corporis
- Impetigo
- Seborrheic dermatitis
- Psoriasis
- Eczema (especially discoid eczema)
- Lichen simplex
- Contact dermatitis
- Pityriasis rosea
Management
General advice
- Hygiene – dry thoroughly between feet after washing or showering
- Avoid use of occlusive footwear
- Use barrier protection – i.e. sandals – when using shared facilities
Topical anti-fungal agents
- OD or BD
- Examples include:
- Terbinafine (Lamisil)
- Some studies suggest this is the most effective agent
- Clotrimazole (canesten)
- Miconazole (Daktarin)
- Terbinafine (Lamisil)
Oral anti-fungal agents
These may be indicated in severe or resistant cases. Options include:
- Terbinafine
- 250mg OD for 2 weeks
- In the case of fungal nail infection, long courses of up to 12 weeks, and frequent LFTs may be required
- Fluconazole
- 150mg once weekly for 6 weeks
- Itraconazole
Prevention of recurrence
- Dry feet thoroughly after bathing
- Avoid occlusive footwear
- Thoroughly dry shoes and boots before wearing
- Clean shower and bathroom floors with bleach
- Treat shoes with anti-fungal powder
References
- Tines corporis – Dermnet NZ
- Murtagh’s General Practice. 6th Ed. (2015) John Murtagh, Jill Rosenblatt
- Oxford Handbook of General Practice. 3rd Ed. (2010) Simon, C., Everitt, H., van Drop, F.
- Beers, MH., Porter RS., Jones, TV., Kaplan JL., Berkwits, M. The Merck Manual of Diagnosis and Therapy