Dermatology Flashcards
Briefly summarise the management of eczema
Management is based on maintenance and management of flares:
- Lifestyle: avoid triggers (foods, stress, washing powders, soaps etc..)
- Emollients
- Use emollients or soap substitutes instead of soap
- Topical steroids
- Wet wraps during flares
- Other specialist management in severe eczema: zinc impregnated bandages, topical tacrolimus, phototherapy, oral corticosteroids, other immunosuppressants (e.g. azathioprine, methotrexate)
State some examples of:
- Thin emollient creams
- Thick, greasy emollient creams
Thin creams:
- E45
- Diprobase cream
- Oilatum cream
- Aveeno cream
- Cetraben cream
- Epaderm cream
Thick, greasy emollients:
- 50:50 ointment (50% liquid paraffin)
- Hydromol ointment
- Diprobase ointment
- Cetraben ointment
- Epaderm ointment
In eczema, the thicker the skin the weaker the steroid required; true or false?
FALSE; thicker the skin the stronger the steroid required
State an example of a:
- Mild
- Moderate
- Potent
- Very potent
… topical steroid used in eczema
The steroid ladder from weakest to most potent:
- Mild: Hydrocortisone 0.5%, 1% and 2.5%
- Moderate: Eumovate (clobetasone butyrate 0.05%)
- Potent: Betnovate (betamethasone 0.1%)
- Very potent: Dermovate (clobetasol propionate 0.05%)
Discuss which areas of body are commonly affected by eczema in:
- Infants
- Children
- In infants, primarily involves the face, the scalp, and the extensor surfaces of the limbs
- In children and adults often localized to the flexure of the limbs
What is the most common organism causing bacterial skin infections in patients with eczema?
Discuss the management
- Staphylococcus aureus
- Management:
- Oral abx (e.g. flucloxacillin)
- If severe may require admission & IV abx
What is eczema herpeticum?
- Viral skin infection caused by HSV or VZV
- HSV-1 is most common causative organism
Are investigations typically done prior to starting treatment for eczema herpeticum?
Treatment usually started based on clinical appearance but can do viral swabs of vesicles to confirm diagnosis
What is eczema herpeticum?
- Viral skin infection caused by HSV or VZV
- HSV-1 is most common causative organism
Discuss the presentation of eczema herpeticum
- Hx of skin condition (e.g. eczema)
- Widespread, painful, vesicular rash
-
WITH systemic features:
- Fever
- Lethargy
- Irritability
- Lymphadenopathy
- Reduced oral intake
Discuss management of seborrhoeic dermatitis in infants
- Reassure parents (not serious, often resolves spontaneously by 8months)
- Use olive oil to loosen scales, brush gently with baby brush then wash off with shampoo
- Bath in emollients as oppose to soap if other areas affected
- If not effective, next step is a topical antifungal cream (e.g. clotrimazole or miconazole) for up to 4 weeks
- If severe, mild topical steroids (e.g.1% hydrocortisone) may be used
Discuss the management of seborrheic dermatitis of scalp (commonly occurs in adolescents & adults)
- First line= ketoconazole shampoo (leave for 5 mins before washing)
- If severe itching= topical steroids
Discuss the management of seborrhoeic dermatitis of face & body
- First line= antifungal cream (e.g. clotrimazole or miconazole)
- Second line= topical steroid (e.g. 1% hydrocortisone)/
Which of the two types of psoriasis are medical emergencies?
- Pustular psoriasis
- Erythrodermic psoriasis
Discuss the management of eczema herpeticum
-
Aciclovir
- Mild-moderate: PO
- Severe: IV
State some potential complications of eczema herpeticum
- Can be life-threatening if immunocompromised
- Bacterial superinfection (leading to more severe illness)
. Briefly describe two types of contact dermatitis
Irritant Contact Dermatitis
- Common
- Non-allergic
- Only areas exposed are affected
- Common on hands
- Stinging, burning, tightness are common symptoms
- Erythema, crusting (vesicles less common in irritant)
Allergic Contact Dermatitis
- Uncommon
- Type IV hypersensitivity reaction
- Areas that are not directly exposed may also be affected
- Often seen on head following hair dye use
- Itching is common symptom
- Erythema, vesicles, weeping eczema (if more severe)
Management
- Avoiding contact with irritant/allergen
- Emollients
- Consider of topical corticosteroids
- Treat any secondary skin infection
What proportion of pts with psoriasis had symptoms that started in childhood?
⅓
Remind yourself of the different types of psoriasis; briefly describing the presentation of each
- Chronic plaque psoriasis (most common in adults): plaques that are thickened, erythematous, silver scaled, extensor surfaces & scalp
- Guttate psoriasis (2nd most common in adults, commonly occurs in children): small raised papules across trunk & limbs, papules are erythematous and may be scaley. Over time papules can turn to plaques. Triggers: streptococcal throat infection, stress, medications.
- Inverse psoriasis: flexor areas affected, erythema, lacks scales, smooth
- Pustular psoriasis (rare): pustules form under erythematous skin- the pus is not infectious. May be systemically unwell.
- Erythrodermic psoriasis (rare): extensive erythematous areas covering most of skin. Get exfoliation of large areas of skin leaving raw exposed areas.
Presentation of psoriasis in children may be different to that in adults however there are some specific signs that are suggestive of psoriasis; state these
- Auspitz sign: areas of bleeing when plaques are scraped off
- Koebner phenomenon: lesion develops in area of skin trauma
- Residual pigmentation: alterations to pigmentation after lesion resolved (darker)
Briefly describe the management of psoriasis (more in special senses block)
- Regular emollients
- First line:
- Potent topical corticosteroids
- Topical vitamin D analogues
- Second line: increase Vit D to BD & stop steroid
- Third line increase steroid to BD & stop vit D
- Others: coal tar preparations, topical dithranol, phototherapy with narrow band UV B light
- Psychosocial support
If topical treatments fail may be started on unlicensed systemic treatments e.g. methotrexate, retinoids, biologics etc..
NOTE: dovobet & enstilar contain both potent steroid & vit D analogue. Not licensed in children but may be prescribed by specailist.
*****Topical calcineurin inhibitors (e.g. tacrolismus) usually only used in adults
Describe the pathophysiology of acne vulgaris
Acne is caused by chronic inflammation +/- infection in the pilosebaceous units. Acne occurs due to:
- Increased production sebum (androgens increase it)
- Trapping of keratin (dead skin cells)
- Blockage of pilosebaceous unit
… leading to swelling and inflammation of the pilosebaceous unit.
Also thought that excessive growth of Propionibacterium acnes bacteria worsens acne (hence many treatments aim to reduce these bacteria)
State some conditions associated with psoriasis
- Nail psoriasis
- Psoriatic arthritis
- Psychosocial (depression, anxiety)
- Obesity
- Hypertension
- Hyperlipidaemia
- T2DM
Describe the presentation of acne vulgaris
Usually presents as erythematous, inflamed, sore spots typically on face, back & upper chest. Specific skin changes/signs include:
- Macules
- Papules
- Pustules
- Closed comedones
- Open comedones (blackheads)
- Ice prick scars (small indentation in skin where acne lesion was)
- Hypertrophic scars (small lumps in skin after acne lesion healed)
- Rolling scars (irregular wave-like irregularities of skin that remain after acne healed)
What are aims of acne management?
- Reduce symptoms
- Reduce risk of scarring
- Minimise psychosocial impact
Briefly discuss the management of acne vulgaris (more in special senses block- including mechanisms of action, ADRs etc)
- First line:
- Topical retinoid (e.g. adapalene) + topical benzoyl peroxide
- Topical retinoid (e.g. tretinoin) + topical clindamycin
- Topical benzoyl peroxide + topical clindamycin
- IF PERSON DOES NOT WANT retinoid or abx can try topical benzoyl peroxide monotherapy
- Second line: add oral tetracycline abx (e.g. lymecycline, doxycycline) *DO NOT use topical & oral abx in combination. Always prescribe topical benzoyl peroxide to reduce risk antibiotic resistance
- Third line: add COCP (co-cyprindiol is most effective due to anti-androgen effect)
- Fourth line: add oral isotretinoin (specialist)
What is urticaria?
Describe pathophysiology
- “Hives”- small itchy lumps on skin which may have associated patchy erythematous rash, angioedema & flushing. Can be acute or chronic.
- Due to release of histamine and other inflammatory mediators by mast cells in skin. Can be due to allergic reaction (most commonly) or autoimmune reaction (as in chronic idiopathic urticaria)
State some potential causes of acute urticaria
- Allergies to food, medications or animals
- Contact with chemicals, latex or stinging nettles
- Medications
- Viral infections
- Insect bites
- Dermatographism (rubbing of the skin)
Chronic urticaria is when rash persists or comes and goes for more than 6 weeks. There are 3 sub classifications; state & describe each
- Chronic idiopathic urticaria (most likely autoimmune): unknown cause or trigger
- Chronic inducible urticaria: induced by certain triggers e.g. sunlight, temp change, exercise, dermatographism, strong emotions
- Autoimmune urticaria: associated with underlying autoimmune condition
Discuss the management of urticaria
- Identify trigger & avoid
- Non-sedating antihistamine e.g. loratadine, cetirizine, fexofenadine (first choice in chronic urticaria) for up to 6 weeks
- If severe, consider oral steroids (e.g. prednisolone for up to 7 days)
- May refer to specialist for: LTRAs (e.g. montelukast), omalizumab (targets IgE), ciclosporin
At what age is nappy rash most common?
9-12 months
Remind yourself of risk factors for nappy rash
- Delayed changing of nappies
- Irritant soap products and vigorous cleaning
- Certain types of nappies (poorly absorbent ones)
- Diarrhoea
- Oral antibiotics predispose to candida infection
- Pre-term infants