Dermatology Flashcards
What is eczema
Common, chronic atopic, inflammatory skin condition caused by defects in normal continuity of skin barrier leading to inflammation of skin
Associations of eczema
- Asthma, hayfever, allergic rhinitis
- Family history
- Breast feeding decreases risk
Triggers of eczema flares
- Soaps, detergents, shower gels, bubble baths, washing-up liquids
- Skin infections (staph aureus)
- Extremes of temperature
- Abrasive or synthetic fabrics
- Dietary factors
- Inhaled allergens = house, dust mites, pollen, pet dander, mould
- Stress/ emotional events
- Hormonal changes in women = pregnancy, menstrual cycle
Presentation of eczema
- Typically affects flexor surfaces, skin folds, elbows and behind knees
- Pruritus
- Onset within first 3m of life but can occur later
- Dry red skin skin
- Presents in flares
Diagnosis criteria for eczema
- Itchy skin + 3 of:
o Itchiness in skin folds in front of elbows and back of knees
o History of asthma or hay fever
o Generally dry skin
o Visible patches of eczema in skin folds
o Onset in first 2 years of life
General advice for eczema
Avoid woollen clothes, extremes of temp, hot baths, scratching
Management of eczema
- Emollients
o Creams < lotions < ointments
o Apply every 4 hours or at least 3-4x per day
o Use >500ml/week
o Bath/shower emollients available - Steroids
o Bring exacerbation under control
o Use steroids at first sign of flare-up
o Apply before emollients 1-2x per day
o Mild = 1% hydrocortisone
o Moderate = Eumovate
o Potent = Betnovate
o Very potent = dermovate
Management of severe or complicated eczema
- Antibiotics (Tx of staph infection)
o Flucloxacillin for 1-2 wks - Immune modulating agents
o Pimecrolimus and tacrolimus - Wet wraps
- Severe eczema
o Zinc impregnated bandages
o Topical tacrolimus
o Phototherapy
o Systemic immunosuppressants
o Oral ciclosporin
Complications of eczema
- Lichenification = Skin becomes thickened and leathery
- Bacterial infection (staph aureus) = Crusting and weeping of lesions with surrounding erythema
- Eczema herpeticum = Eczema with co-exisiting herpes simplex infection
- Cataracts
- Erythemic eczema
Side effects of topical steroids
thinning of skins, bruising, tearing, stretch marks, enlarged blood vessels, systemic absorption
Features of acne rosacea
- Typically red rash affects nose, cheeks and forehead often with inflammatory papules
- Facial Flushing
- Increased skin sensitivity and stinging sensations
- Later develops into persistent erythema with papules and pustules and nodes without comedones
- Telangiectasia
- Rhinophyma
- Facial oedema
- Seborrheic dermatitis
- Sunlight may exacerbate symptoms
Management of acne rosacea
- Predominant erythema/flushing
o Topical brimonidine gel PRN - Mild-mod papules +/- pustules
o Topical ivermectin
o Alternatives: topical metronidazole or topical azelaic acid - Mod-severe papules +/- pustules
o Topical ivermectin + oral doxycycline
General advice for acne rosacea
- Daily suncream
- Camouflage creams to conceal redness
- Gentle soap-free cleanser
- Avoid oil based creams and topical steroids
- Avoid factors that cause facial flushing heat, wind, sudden changes in temp, alcohol, excessive exercise, hot baths, spicy foods, hot drinks
- Cool packs
Management of extreme acne rosacea
- Laser treatment for telangectasia
- Surgical correction of rhinophyma
Referral criteria for acne rosacea
- Symptoms not improved with optimal management in primary care
- Patients with rhinophyma
Complications of acne rosacea
- Blepharitis
- Conjunctivitis
- Rhinophyma = large bulbous nose
Associations for acne vulgaris
- PCOS
- Steroid use
- Certain skincare products (heavy makeup)
- Colonisation by Propionibacterium acnes
Features of acne vulgaris
- Typically affects face, neck and upper trunk
- Greasy skin
- Comedones
o Open comedomes blackheads
o Closed comedomes whiteheads - Inflammation
- Papules Small, inflammatory usually raised red lesions
- Pustules (more superficial)
- Nodules = bigger papules
- Cysts Develop when further infection and inflammation due to P.acnes
- Atrophic scars
Classification of acne vulgaris
- Mild: open and closed comedones +/- sparse inflammatory lesions
- Moderate: widespread non-inflammatory lesions and numerous papules and pustules
- Severe: extensive inflammatory lesions, nodules, pitting and scarring
General advice for acne vulgaris
o Washing twice daily with soap and water
o Avoid use of oily products
Pharmacological management of acne vulgaris
- topical retinoids (adapeline), benzoyl peroxide
- combination therapy (topical Abx, retinoid, benzoyl peroxide)
- Oral Abx
o Tetracyclines (lymecycline, doxycycline)
Avoid in pregnancy or breastfeeding and children <12
o Erythromycin or clindamycin Used in pregnancy
o Single Abx used for max 3m
o Topical retinoid or benzyl peroxide always co-prescribed - COCP alternative to oral Abx in women
- Oral isotretinoin under specialist supervision
o Do not use in pregnancy
Referral criteria for acne vulgaris
- Patients with acne congolbat
- Patients with nodulo-cystic acne
- Considered with
o Mild to moderate acne that has not responded to two completed courses of treatment
o Moderate to severe acne that has not responded to previous treatment that includes an oral antibiotic
o Acne with scarring
o Acne with persistent pigmentary changes
o Acne is causing or contributing to persistent psychological distress or mental health
Complications of acne vulgaris
- Depression, anxiety, social phobia
- Scarring
Epidemiology of psoriasis
- Peaks of incidence at 15-25 and 50-60
- Caucasian
Precipitating factors for psoriasis
- Trauma
- Infection
- Drugs BB, lithium, anti-malarials, NSAIDs, ACEi, infliximab, withdrawal of systemic steroids
- Emotional stress
- Sunlight
- Puberty
- Menopause
- Alcohol
- Obesity
- Smoking
Associated disorders for psoriasis
- Psoriatic arthritis
- IBD
- Uveitis
- Coeliac disease
- Metabolic syndrome = T2DM, hypertension, hyperlipidaemia, gout, cardiovascular disease
Presentation of psoriasis
- Symmetrical red scaly plaques (white/silvery coloured)
- Extensor surfaces front of knees, back of elbows
- Itchy ± excoriation/lichenificiation
- Pitting nails, onycholysis, subungual hyperkeratosis, BEAUs lines, loss of nail
Lifestyle management of psoriasis
smoking cessation
reduce alcohol
weight loss
avoid sun exposure
manage stress
Management of psoriasis
- Regular emollients help reduce scale loss and reduce pruritus
1. Potent corticosteroid + vitamin D analogue (calcipotriol)
a. Applied separately, one in morning and one in evening
b. Up to 4 wks as initial treatment
2. if no improvement after 8 wks vitamin D analogue twice daily
3. if no improvement after 8-12 wks
o Potent corticosteroid applied twice daily for up to 4 wks
o Or coal tar preparation applied once or twice daily - Short-acting dithranol
- Scalp psoriasis
o Potent topical corticosteroids used once daily for 4 weeks
Indications for referral to secondary care for psoriasis
- > 10% of body surface area affects
- Psoriasis not responding to topical treatment
- Psoriasis in children
- Psoriasis having major impact on psychological health
Secondary care management options for psoriasis
o Phototherapy
o Oral methotrexate
o Ciclosporin
o Systemic retinoids
o Biological agents
Complications of psoriasis
- Depression, anxiety
- Reduced rates of employment
- Koebner phenomenon = skin lesions appear at site of injury
What is cellulitis
Bacterial infection that affects the dermis and deeper subcutaneous tissues
Causes of cellulitis
- Streptococcus pyogenes
- Staph. Aureus
Presentation of cellulitis
- Unilateral erythematous rash and swelling
- Usually on shins
- Blisters and bullae with more severe disease
- Fever
- Malaise
- Nausea
Classification of cellulitis
Eron
- I - No signs of systemic toxicity and no uncontrolled co-morbidities
- II – either systemically unwell or systemically well but with co-morbidity which may complicate or delay resolution of infection
- III - significant systemic upset (acute confusion, tachycardia, tachypnoea, hypotension) or unstable co-morbidities that may interfere with response to treatment, or a limb-threatening infection due to vascular compromise
- IV – sepsis syndrome or a severe life-threatening infection such as necrotising fasciitis
Admission criteria for cellulitis
- Eron class III-IV
- Severe or rapidly deterioriating cellulitis
- Aged <1 year or frail
- Immunocompromised
- Significant lymphoedema
- Facial cellulitis or periorbital cellulitis
Management of cellulitis
- Eron class I – oral flucloxacillin (1st line)
- Eron class II – IV/oral Abx
- Eron class III-IV - admit and oral/IV co-amoxiclav or clindamycin or cefuroxime or ceftriaxone
- Penicillin allergic = oral clarithromycin, erythromycin (pregnancy) or doxycycline
Risk factors for skin cancer
- Age
- Sun bed use
- Fair skin
- Hx of sunburn
- Hx of living overseas/places with lot of sun exposure
- FHX
- Outdoor occupations
- Phototherapy
Assessing a skin lesion
- A = asymmetry
- B = border irregularity
- C = colour (multiple)
- D = diameter >7mm
- E = evolution/enlargement
What is actinic keratoses
Common premalignant skin lesion that develops due to chronic sun exposure
Presentation of actinic keratoses
- Small, crusty or scaly lesions
- Pink, red, brown or same colour as skin
Management of actinic keratoses
- Prevention sun avoidance, sun cream
- Fluorouracil cream 2-3 wks
- Topical diclofenac
- Topical imiquimod
- Cryotherapy
- Curettage and cautery
Risk factors for squamous cell carcinoma
- Smoking
- Sun exposure
- Actinic keratosis/solar keratoses
- Age
- Skin trauma
- Exposure to carbon containing compounds
- Asbestos
- Arsenic
- Ionising radiation
- Metals
Presentation of SCC
- Solitary papule/nodule often eroded at centre or crusty, purulent or bleeding
- Fleshy lesion
- May resemble giant warts ± pain
- Sun-exposed area
- Hard, scaly, dome-like scturctures
- Can bleed or itch
- Lower lip if related to smoking
- Bowen’s disease = SCC in situ
Treatment of SCC
- Definitive = surgical excision with minimum 2mm margin
- Topical cream
o 5-fluorouracil applied 1-2x daily for 4 weeks - Cryotherapy
- Solar keratoses = topical agents or cryotherapy
What is melanoma
Proliferation of atypical melanocytes with potential for dermal invasion and widespread metastases
Epidemiology of melanoma
- Women common on lower legs
- Men common on back
- Australia has highest incidence
Risk factors for melanoma
- Sun exposure (sunburn before age of 10)
- Male gender
- > 50 moles (benign naevi)
- FHx or PMH of melanoma or other skin cancers
- Fair complexion
- Smoking
- Age
- Previous sunburn
Types of melanoma
- Lentigo maligna melanoma
o Large, flat, dark lesion
o Usually on face or other sunexposed areas in elderly patients - Superficial spreading melanoma
o Most common on legs of women and torso/.back of men
o Slightly raised plaque - Nodular melanoma
o Often dark coloured but can be pearly or lack pigment
o Grow rapidly but rarely metastasise - Acral and subungal melanoma
o Most common in Black Africans
o Palms or soles or subungal skin
Metastatic spread of melanoma
- Local lymph nodes
- Satellite lesions
- Skin
Management of melanoma
Excision
Follow up of melanoma
o <1mm thickness 6 monthly for 2 years
o 1-2mm thickness 4 monthly for 2 years, 6 monthly for 2 years, yearly for 10 years
o >2mm thickness annual CXR and regular GP and specialist FU
Presentation of Basal cell carcinoma
- Pearly nodule with raised red edge
- Maybe scaly
- May be ulcerated
Management of BCC
- Surgical excision with 3mm margin
- Imiquimod applied once daily, 5 days a week for up to 6 weeks
- Cryotherapyd
Risk factor for shingles
- Immunocompromised
- HIV, Hodgkin’s lymphoma and bone marrow transplants
Cause of shingles
Reactivation of varicella zoster virus (chickenpox) usually within dorsal root ganglia
Presentation of shingles
- Pain and paraesthesia in dermatomal distribution priced rash for days
- Malaise, myalgia, headache and fever
- Rash = consists of papules and vesicles restricted to same dermatome
o Crust formation and drying occurs over next week with resolution in 2-3 weeks
Management of shingles
- Oral antiviral therapy begun within 72 hrs of rash onset
o Oral acyclovir x5 daily
o Or oral valiciclovir/famciclovir x2 daily - Topical antibiotic treatment for secondary bacterial infection
- Analgesia = ibuprofen
Complications of shingles
- Ophthalmic branch of trigeminal nerve damage
- Post herpetic neuralgia = Pain lasting more than 4 months after developing shingles
Causes of acanthosis nigricans
- T2DM
- Gastrointestinal cancer
- Obesity
- PCOS
- Acromegaly
- Cushing’s disease
- Hypothyroidism
- Familial
- Prader-Willi syndrome
- Drugs = COCP, nicotinic acid
Presentation of scabies
- Widespread pruritus
- Linear burrows on side of fingers, interdigital webs and flexor aspects of wrists
- Infants = face, scalp
- Scratching excoriation, infection
Management of scabies
- permethrin 5%
- malathion 0.5%
General advice for scabies
- Pruritus persists 4-6 wks post eradication
- Avoid close physical contact with others until treatment complete
- All household and close physical contacts treated at same time even if asymptomatic
- Launder, iron or tumble dry clothing, bedding, towels on first day of treatment
Complications of scabies
- Crusted scabies (suppressed immunity)
o Tx = Ivermectin
o Isolation
Presentation of seborrheoic keratoses
- Large variation in colour from flesh to light-brown to black
- ‘Stuck on’ appearance
- Keratotic plugs
Management of seborrhoeic keratoses
- Reassurance about benign nature of lesion is option
- Removal curettage, cryosurgery, shave biopsy
What is seborrhoeic dermatitis
Chronic dermatitis thought to be caused by inflammatory reaction related to proliferation of normal skin inhabitant
Cause of seborrhoeic dermatitis
Malassezia furfur (pityrosporum ovale)
Associations of seborrhoeic dermatitis
- HIV
- Parkinson’s disease
Presentation of seborrheoic dermatitis
Eczematous lesions on sebum-rich areas: scalp, periorbital, auricular, nasolabial folds
Management of seborrhoeic dermatitis
- Scalp
o Ketoconazole 2% shampoo
o OTC preparations containing zinc pyrithione and tar
o Selenium sulphide and topical corticosteroid - Face and body
o Topical antifungals ketoconazole
o Short course Topical steroids
Complications of seborrhoeic dermatitis
Otitis externa
Blepharitis
Causes of lichen planus
- Drugs = gold, quinine, thiazides
Presentation of lichen planus
- Itchy, popular rash most common on palms, soles, genitalia and flexor surfaces of arms
- Rash often polygonal in shape with white lines pattern on surface Wickham’s striae
- Koebner phenomenon
- Oral involvement white-lace pattern on buccal muosa
- Nails thinning of nail plate, longitudinal ridging
Management of lichen planus
- Potent topical steroids
- Benzydamine mouthwash or spray
- Oral steroids or immunosuppression
What is erythema nodosum
Inflammation of subcutaneous fat
Causes of erythema nodosum
pregnancy, strep infections, sarcoidosis, TB, IBD, drugs (penicillins, sulphonamides, oral contraceptive pill)
Presentation of erythema nodosum
Symmetrical, erythematous, tender, nodules which heal without scarring
Management of erythema nodosum
treat underlying cause, provide Sx relief with analgesia and rest
Presentation of pretibial myxoedema
o Symmetrical, erythematous lesions seen in Graves
o Shiny, orange peel skin
Presentation of pyoderma gangrenosum
o Initially Small red papule
o Later deep, red, necrotic ulcers with violaceous border
Presentation of necrobiosis lipoidica diabeticorum
o Shiny, painless areas of yellow/red skin typically on shin of diabetics
o Telangiectasia
What is erythema multiforme
Hypersensitivity reaction most commonly triggered by infections
Causes of erythema multiforme
- Viruses HSV
- Idiopathic
- Bacteria mycoplasmia, strep
- Drugs penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, Oral contraceptive pill, nevirapine
- Connective tissue disease (SLE)
- Sarcoidosis
- Malignancy
Presentation of erythema multiforme
- Target lesions
- Initially seen on back of hands/feet before spreading to torso
- Upper limbs > lower limbs
- Pruritus
- Sore throat followed by fever, myalgia and lethargy
- Erythema multiforme major mucosal involvement
Causes of urticaria
- Acute
o Allergies to food, medications, animals
o Contact with chemicals, latex or stinging nettles
o Medications
o Viral infections
o Insect bites
o Dermatographism (rubbing of skin) - Chronic
o Chronic idiopathic urticaria no clear underlying cause or trigger
o Chronic inducible urticaria
Sunlight
Temperature
Exercise
Strong emotions
Hot/cold weather
Pressure
o Autoimmune urticaria Systemic lupus erythematosus
Management of urticaria
- Antihistamines (fexofenadine)
- Short course oral steroids for severe flares
- Specialist treatment
o Anti-leukotrienes (montelukast)
o Omalizumab
o Cyclosporin
Causes of nectrotising fasciitis
- Type 1 = mixed anaerobes and aerobes
- Type 2 = streptococcus pyogenes
Risk factors for necrotising fasciitis
- Recent trauma, burns or soft tissue infections
- Diabetes mellitus
o Esp if taking SGLT-2 inhibitors - IVDU
- Immunosuppression
Most common site of nectrotising fasciitis
perineum (Fournier’s gangrene)
Presentation of nectrotising fasciitis
- Acute onset
- Pain, swelling, erythema at affected site
o Rapidly worsening cellulitis with pain out of keeping with physical features
o Extremely tender over infect tissue with hypoaethesia to light touch - Late signs
o Skin necrosis
o Crepitus/gas gangrene
o Fever
o Tachycardia
Management of necrotising fasciitis
- Urgent surgical referral for debridement
- IV Abx
