Synopsis
Distinguish coin-shaped discoid eczema from fissured asteatotic eczema, exclude dermatophyte infection and venous disease, and treat dryness and inflammation without masking important mimics.
- Discoid eczema forms very itchy round or oval plaques, often weepy and crusted early and dry or scaly later; it commonly mimics tinea corporis.
- Asteatotic eczema produces superficial intersecting cracks on very dry skin, often shins of older adults in cold dry conditions.
- On brown or black skin, active discoid plaques may appear dark brown, purple or paler and often leave persistent pigment change.
- Scrape an untreated active scaly border when dermatophyte infection is plausible before escalating topical corticosteroid.
- Reduce hot bathing and harsh soap, use a generous leave-on emollient and apply a site-appropriate topical corticosteroid to active plaques for a defined course.
- A solitary plaque that remains indurated, ulcerated or treatment-resistant needs biopsy consideration rather than repeated empirical cream.
- For Discoid and asteatotic eczema, document body sites, severity, sleep and function, recent treatment, infection features and what the patient can realistically apply each day.
- In Discoid and asteatotic eczema, reassess the diagnosis when a well-used, correctly potent regimen fails rather than repeatedly intensifying treatment without examining adherence, exposure and mimics.
Key red flags
Systemic illness, painful expansion, purpura, widespread detachment, unilateral ulceration, palpable tumour, treatment-resistant annular disease or major lower-leg oedema requires broader investigation.
A solitary enlarging indurated plaque with bleeding, ulceration or failure of adequate therapy requires prompt specialist assessment.
Investigation priorities
Distinguish discoid and asteatotic patterns from psoriasis, venous disease and a fungal reservoir.
Management branches
Craquelé fissures occur on dry skin without infection, tumour features or major venous disease.
- Shorten hot washing, stop harsh soap and apply a rich fragrance-free leave-on emollient at least twice daily and after washing.
- Use a site-appropriate topical corticosteroid on inflamed fissured areas for a defined short course while continuing emollient beyond clearance.
- Review heating, humidity, mobility and adequate product quantity and reassess if fissures become painful, wet or widespread.