GPAtlas🧭 When to suspect
Suspect a dermatophyte (tinea) infection – a fungal infection of keratin in the skin, hair or nails, commonly called ringworm – whenever there is an itchy, red, scaly rash that is asymmetrical or has a leading edge. The classic body lesion is annular (ring-shaped) with a raised, advancing scaly edge and central clearing. Dermatophytes need keratin to grow, so infection is confined to skin, hair and nails and does not involve mucosal surfaces.
The presentation is named by site. Tinea pedis (athlete's foot) is the commonest pattern in adults, while tinea capitis (scalp ringworm) is the one to think of in children. Infection readily spreads from one site to another – for example athlete's foot seeding the groin – so always look for a second site and ask about communal areas, occlusive footwear, sport, animal contact, and household members with a similar rash.
| Type (site) | Common name | Typical features |
|---|---|---|
| Tinea corporis (body) | Ringworm | Annular scaly plaque with a raised advancing edge and central clearing |
| Tinea cruris (groin) | Jock itch | Itchy red scaly rash of groin/inner thigh, usually bilateral; often spares the scrotum |
| Tinea pedis (foot) | Athlete's foot | Itchy maceration/fissuring between the toes, or dry "moccasin" scaling of the soles |
| Tinea capitis (scalp) | Scalp ringworm | Scaly patches with broken hairs/hair loss, ± a kerion (boggy inflamed swelling); mainly children |
| Tinea unguium (nail) | Onychomycosis (fungal nail) | Thickened, discoloured (white/yellow/brown), crumbly nail with onycholysis (lifting off the bed) |
| Tinea manuum (hand) | – | Dry scaling of one palm, classically with both feet involved ("two feet–one hand") |
Source: NICE · DermNet
🔒 Sign up free to read the full topic
You're viewing a free preview. Create a free account to unlock the rest.
Sign up free →Sample topics are open to everyone in the Free Sample Bundle.