DERM - Common Chronic Skin Conditions

Question 1

Acne Vulgaris

Pathophysiology
Risk Factors/Modifiers
Clinical Features
General Management/Advice

Answer 1

1. ) Pathophysiology
   - androgens trigger ↑sebum and comedone formation
   - sebum and comedones causes blockage of pilosebaceous ducts which leads to inflammation
   - pilosebaceous glands mostly on face, back, chest
2. ) Risk Factors/Modifiers
   - hormonal: menstrual cycle, PCOS, other endo disor…
   - oil-based cosmetics
   - drugs: steroids (both types), lithium, cyclosporin, oral iodides (can be part of homoeopathic therapies)
   - stress and diet have little effect on acne vulgaris
   - UV light can actually benefit acne
3. ) Clinical Features - greasy skin, excoriation
   - mild: comedones (non-inflammatory) which can be either whitehead (closed) or blackheads (open)
   - moderate: inflammatory (papules, pustules, nodules)
   - severe: atrophic/ice-pick scars, hypertrophic/keloid scars, hyperpigmentation
4. ) General Management/Advice
   - avoid over-cleaning, acne is not due to poor hygiene
   - use a non-alkaline detergent cleansing product BD
   - avoid oil-based products e.g. make-up, sunscreen
   - avoid persistent picking or scratching as –> scarring
   - not enough evidence to support specific diets

Question 2

Management of Acne Vulgaris

Mild/Comedonal to Moderate/Inflammatory Acne
Moderate to Severe
Referral to Dermatology
Severe/Scarring

Answer 2

1. ) Mild/Comedonal to Moderate/Inflammatory Acne
   - mild: adapalene or BPO, OR epiduo (has both)
   - moderate: epiduo or duac (BPO + clindamycin)
   - review each treatment after every 12wks
2. ) Moderate to Severe - or not responding to above
   - combine oral antibiotics with a topical combination^^
   - Abx: lymecycline or doxycycline OD –> BD
   - erythromycin or clarithromycin in pregnancy and <12s as tetracyclines are contraindicated as they affect skeletal development and cause tooth discolouration
   - oral abx used for 3 mths, maximum 6 if still clearing
   - the COCP can be an alternative or alongside
3. ) Referral to Dermatology
   - severe: visible/risk of scarring or hyperpigmentation
   - moderate acne only partially responding to treatment
   - psychological distress regardless of physical signs
4. ) Severe/Scarring - start on treatment above and referral to dermatology for treatment w/ isotretinoin
   - isotretinoin (Roaccutane) is an oral retinoid
   - side effects: teratogenic, dry skin, lips, eyes, fragile skin, alopecia, photosensitivity, deranged LFTs, epistaxis, ↑triglycerides, myalgia, arthralgia, depression/suicide, intracranial hypertension
   - monitoring: U+Es, LFTs, appropriate contraception (co-prescribed two forms of contraception)

Question 3

Atopic Eczema/Dermatitis

Pathophysiology
Triggers
Clinical Features
Assessing Severity

Answer 3

1. ) Pathophysiology - primary defect in the skin barrier function due to mutation of filaggrin gene
   - immunological changes secondary to ↑ antigen penetration through a deficient epidermal barrier
   - often presents in childhood but most grow out of it
   - personal or family history of atopy is very common
2. ) Triggers - can cause spontaneous flare-ups
   - stress, skin infection, soap/detergent, rough clothes
   - winter: central heating drying out skin
   - specific triggers: animal dander/saliva, food, pollen house-dust mites
3. ) Clinical Features
   - itchy, erythematous, scaly, papulovesicular rash
   - dry skin, excoriations –> lichenification (thickening, hyperpigmentation, skin lines, suggests they have had eczema in that location before)
   - distribution: poorly defined, face in infants, followed by flexural involvement, can become widespread
   - can be diagnosed using a patch test
4. ) Assessing Severity
   - mild: dry skin, infrequent itching +/- areas of redness
   - moderate: dry skin, frequent itching, redness +/- excoriation and localized skin thickening
   - severe: widespread dry skin, itchy+++, redness w/ bleeding, oozing, cracking, hyperpigmentation
   - infected: weeping/crusted, or pustules w/ fever

Question 4

Management of Atopic Eczema

General Advice
Mild Eczema
Moderate Eczema
Severe Eczema

Answer 4

1. ) General Advice
   - avoid triggers: e.g. clothing, soaps, animals, heat
   - avoid scratching, rub area w/ fingers to alleviate itch
   - use anti-scratch mittens for babies with eczema
   - ointments are more suitable for night-time use
2. ) Mild Eczema
   - emollients: continuous and generous usage
   - mild topical corticosteroids for flare-ups
3. ) Moderate Eczema - as above including:
   - moderate topical corticosteroids for flare-ups
   - use mildly potent if in face, flexures, genitals, or axilla
   - maintenance therapy to prevent recurrent flare-ups: use weaker topical steroid twice a week
   - occlusive dressing and dry bandages
   - PO antihistamines: severe itch/urticaria, non-sedating (Cetirizine) or sedating if can’t sleep (chlorphenamine)
4. ) Severe Eczema - as above including:
   - potent topical steroids for flare-ups, moderate potency if in the sensitive areas e.g. face, genitals
   - topical calcineurin inhibitors: steroid-sparing agents, proptic (tacrolimus) pr elidel (pimecrolimus)
   - PO prednisolone 30mg OD-1w if eczema causes psychological distress

Question 5

Complications of Eczema

Eczema Herpeticum
Infected Eczema
Erythroderma
Side Effects of Topical Corticosteroids

Answer 5

1. ) Eczema Herpeticum - disseminated HSV1/2 infection due to impaired skin protection from (atopic) eczema
   - monomorphic punched-out erosions
   - rapidly progressing painful vesicular rash which can ulcerate and crust, bleed, and leak pus
   - may be systemically unwell: fever, malaise
   - more common in children
   - diagnosis confirmed with a swab + Tzanck test
   - dermatological emergency, treat w/ IV aciclovir
   - uncommonly, can be caused by Coxsackie virus which is self-limiting and doesn’t respond to aciclovir
2. ) Infected Eczema - a superficial bacterial infection
   - usually caused by staphylococci/streptococci, take skin swab, treat w/ oral flucloxacillin or clarithromycin
   - topical fusidic acid if localised areas of infection
   - urgent referral (2WW) if it doesn’t respond to treatment
3. ) Erythroderma - widespread erythema affecting >90% of the skin surface due to exacerbation of eczema
   - dermatological emergency: can result in heat and fluid loss, causing hypothermia and systemic symptoms
4. ) Side Effects of Topical Corticosteroids
   - transient burning/stinging: common in the first 2 days
   - worsening and spreading of an untreated infection,
   - skin thinning (reversible), permanent striae,
   - allergic contact dermatitis, acne (or worsening)
   - mild depigmentation, excessive hair growth
   - telangiectasia

Question 6

Psoriasis

Pathophysiology
Triggers
Chronic Plaque Psoriasis
Other Types of Psoriasis

Answer 6

1.) Pathophysiology - autoimmune disease-causing
inflammation and hyperproliferation of keratinocytes
- due to abnormal ↑T-cells triggering cytokine release
- risk factors: FH, obesity, smoking, HIV
- FH a very strong RF, often presents in young adults

2. ) Triggers
   - stress, excessive alcohol, smoking, sunlight
   - Koebner phenomenon: skin lesions occur at sites of skin injury in otherwise healthy skin
   - infection: HIV, streptococcal (guttate psoriasis)
   - drugs (BALI): ß-blockers, anti-malarials/ACEi/Alcohol), Lithium, Indomethacin/NSAIDs, withdrawal of oral corticosteroids
   - pregnancy: improves but worsens in post-partum
3. ) Chronic Plaque Psoriasis - most common type
   - itchy, well-defined, circular-to-oval, bright red/pink
   - plaques with overlying white or silvery scale
   - symmetrical distribution over extensor (elbows, knees), scalp, lower back, ear, nails, umbilicus, groin
   - large plaque: where small plaques merge (confluent)
   - nail changes: pitting, onycholysis, hyperkeratosis
4. ) Other Types of Psoriasis
   - flexural: smooth, red, non-scaly plaques in flexures
   - guttate: multiple small, tear-drop-shaped, red plaques on the trunk after a Strep infection in young adults
   - pustular: petechiae and pustules on palms and soles
   - generalised/erythrodermic: rare but serious form characterised by erythroderma and systemic illness

Question 7

Management of Chronic Plaque Psoriasis

General Advice
Topical Treatments
Referral to Dermatology
Secondary Care Interventions

Answer 7

1. ) General Advice
   - no cure, only control sx, not an infectious condition
   - lifestyle: smoking cessation, ↓alcohol, weight loss
   - manage stress, anxiety/depression appropriately
   - linked to cardiovascular disease
   - avoid use of oral corticosteroids as it can cause flares of skin lesions
2. ) Topical Treatments - first line, review after 4wks
   - emollient: regular use to reduce scale and itch
   - 1°: potent corticosteroid OD (eg Betnovate) + vitD OD (eg Dovonex) applied at different times, try for 4-8wks
   - 2°: stop corticosteroid, apply vitD BD, try for 8-12wks
   - 3°: stop vitD, apply corticosteroid BD, try for 4wks OR a coal tar preparation applied once or twice daily
   - 4°: combined corticosteroid + vitD OD (e.g. Enstilar), try for 4wks
   - scalp psoriasis: topical potent steroids are first line followed by topical vitamin D
3. ) Referral to Dermatology
   - medical emergency (urgent): suspected generalized pustular psoriasis or erythrodermic psoriasis
   - topical treatment-resistant psoriasis
   - significant impact on wellbing: physical, psych, social
   - referral to rheum if psoriatic arthritis suspected
4. ) Secondary Care Interventions
   - phototherapy: 1°narrowband UVB, 2°psoralen + UVA
   - DMARDs: 1°methotrexate, 2°ciclosporin, 3°acitretin
   - biologics: infliximab, etanercept, ustekinumab

Question 8

Medications for Chronic Skin Conditions

Acne Medication
Emollients
Potentcies of Topical Corticosteroids
Usage of Topical Corticosteroids

Answer 8

1. ) Acne Medication
   - treatments may irritate the skin, especially at the start
   - start w/ short-contact application (wash off after 1hr)
   - Adapalene: topical retinoid only
   - Epiduo: contains adapalene and benzoyl peroxide
   - Duac: contains benzyl peroxide and clindamycin
2. ) Emollients - a mixture of fats and water, rehydrates skin and re-establishes the surface lipid layer
   - lotion (least greasy) –> cream –> ointment (greasiest)
   - use >2-4 times a day, apply ASAP after washing
   - wait 15-30 minutes before applying other topicals
   - pump dispensers ↓risk of bacterial contamination
3. ) Potencies of Topical Corticosteroids
   - potencies: Help Every Budding Dermatologist
   - mild: Hydrocortisone 0.5/1%, moderate: Eumovate
   - potent: Betnovate, very potent: Dermovate
   - potent/very potent not used on the face or genitals
   - v potent only be prescribed by dermatologists
4. ) Usage of Topical Corticosteroids
   - fingertip units (FTU) are used for measurement, different areas of the body require different FTUs
   - in eczema, use for 48hrs after the flare is controlled
   - in psoriasis, don’t use >8w in one site, should have a 4w treatment break where vitD is continued
   - side effects: skin thinning, acne, striae, excessive hair growth, telangiectasia, perioral dermatitis