UKMLA Conditions Categorised by Body System
,Acne Vulgaris
A chronic inflammatory disorder of the pilosebaceous unit, causing comedones, papules, pustules and nodules. Common in adolescence,
driven by androgen-stimulated sebum production, follicular hyperkeratinisation, Cutibacterium acnes colonisation, and inflammation.
Key clinical features
• Comedones — open (blackheads) and closed (whiteheads).
• Inflammatory papules and pustules; nodulocystic lesions in severe disease.
• Typical distribution: face, chest, back.
• Scarring (icepick, boxcar, rolling) and post-inflammatory hyperpigmentation, particularly in darker skin types.
Investigations
• Usually a clinical diagnosis.
• Consider hormonal work-up (e.g. for PCOS) if signs of hyperandrogenism — hirsutism, irregular periods — accompany severe or late-
onset acne in females.
Treatment and management
• Mild disease: topical retinoids ± benzoyl peroxide.
• Inflammatory acne: topical or oral antibiotics, with duration limited to reduce resistance.
• Females: combined oral contraceptive or co-cyprindiol (anti-androgen) can help.
• Severe, resistant or scarring acne: oral isotretinoin (specialist-initiated; teratogenic, requiring strict pregnancy prevention).
Complications
• Scarring and significant psychological impact/low self-esteem
• Post-inflammatory hyperpigmentation
• Isotretinoin side effects — dry skin/lips, mood changes, deranged LFTs/lipids, teratogenicity
, Atopic Dermatitis / Eczema
A chronic, relapsing inflammatory skin condition caused by skin barrier dysfunction (e.g. filaggrin mutations) and immune dysregulation.
Part of the ‘atopic triad’ alongside asthma and allergic rhinitis.
Key clinical features
• Dry, itchy, erythematous skin.
• Flexural distribution in children/adults (antecubital and popliteal fossae); extensor surfaces typically affected in infants.
• Excoriation and lichenification from chronic scratching.
• May develop secondary bacterial (Staph. aureus) or viral (eczema herpeticum) infection.
Investigations
• Usually a clinical diagnosis.
• Patch testing if a specific contact allergen is suspected.
• Skin swab if secondary infection is suspected.
Treatment and management
• Regular emollients — the mainstay of management; avoid irritants/triggers.
• Topical corticosteroids for flares, using a stepped-potency approach.
• Topical calcineurin inhibitors (tacrolimus) for sensitive areas or as steroid-sparing therapy.
• Sedating antihistamines can help itch and sleep disturbance.
• Phototherapy, systemic immunosuppressants, or biologics (e.g. dupilumab) for severe, refractory disease.
Complications
• Secondary bacterial infection
• Eczema herpeticum — disseminated HSV infection; a dermatological emergency
• Sleep disturbance and significant quality-of-life impact
• Skin thinning from steroid overuse