Dermatology Flashcards
What is classified as moderate acne
Widespread non-inflammatory lesions and numerous papules and pustules
What is classified as severe acne
Extensive inflammatory lesions, which may include nodules, pitting, and scarring
First line treatment for mild to moderate acne
12 week course of topical combination therapy:
- Fixed combo topical tretinoin with topical clinda
- Fixed combo topical benzoyl peroxide with topical clinda or topical adapalene
When can topical benozyl peroxide be used as monotherapy?
If combo contraindicated, or person wishes to avoid using topical retinoid or an antibiotic
First line treatment for moderate to severe acne
12 week course of:
- Fixed combo topical adapalene with topical benzoyl peroxide (+/- oral lymecycline or oral doxy)
- Fixed combo topical tretinoin with topical clinda
- Topical azelaic acid + oral lymecycline/doxy
What antibiotic used for acne in pregnancy/breastfeeding?
Erythromycin
Why is minocycline not used in acne anymore
Possibility of irreversible pigmentation
How long can you continue acne treatment including antibiotic (topical or oral)
6 months unless exceptional circumstances
Can antibiotics be used as monotherapy?
No, always co-prescribe topical retinoid or benozyl peroxide to avoid antibiotic resistance
Complication of long term antibiotic use in acne
Gram negative folliculitis
Treatment for gram negative folliculitis occurring as complication from long term abx use in acne
High dose oral trimethoprim
Role of COCP in acne
Can be used as alternative to PO Abx in women
Should be used in combination with topical agents
What COCP useful in acne
Dianette (co-cyprindiol)
Advantage of dianette in acne
Anti-androgen properties
Limitation of dianette in acne
Increased risk of VTE compared to other COCP, so should generally only be used second line, only for 3 months, and with counselling
Role of oral isotretinoin in acne
Only under specialist supervision
Definite referral criteria acne
- Conglobate acne
- Nodulo-cystic acne
What is conglobate acne?
Rare and severe form, mostly in men, extensive inflammaotry papules, suppurative nodules that may coalesce to form sinuses, cysts on trunk
When to consider referral for acne
- Mild to moderate acne not responding to two completed courses of treatment
- Moderate to severe acne not responded to treatment including oral antibiotic
- Acne with scarring
- Acne with persistent pigmentary changes
- Acne causing distress or contributing to persistent psychological distress or mental health disorder
What is erythema nodosum
Inflammation of SC fat, typically causing tender, erythematous, nodular lesions
Causes of erythema nodosum
Infection
Systemic disease
Malignancy/lymphoma
Drugs
Pregnancy
Infections causing erythema nodosum
Streptococci
Tuberculosis
Brucellosis
Systemic disease causing erythema nodosum
Sarcoidosis
Inflammatory bowel disease
Behcet’s
Drugs causing erythema nodosum
Penicillins
Sulphonamides
COCP
First line treatment chronic plaque psorasis
Potent corticosteroid OD + vitamin D analogue OD, up to 4 weeks as initial treatment
Applied seperately, one in morning one in evening
Second line treatment chronic plaque psoriasis
Vitamin D analogue BD
Third line treatment chronic plaque psorasis
Potent corticosteroid BD (up to 4 weeks), or coal tar OD-BD
Other treatment options in primary care chronic plaque psoriasis
Short-acting dithranol
Secondary care management options chronic plaque psoriasis
- Phototherapy
- Photochemotherapy
- Systemic therapy
What kind of phototherapy given in chronic plaque psorasis
Narrowband UVB light, if poss 3 times a week
What kind of photochemotherapy chronic plaque psoriasis
Psoralen and UVA light (PUVA)
Adverse effects of phototherapy in chronic plaque psoriasis
Skin ageing
Squamous cell carcinoma
Systemic therapies used in chronic plaque psoriasis
Methotrexate (first line)
Ciclosporin
Systemic retinoids
Biological agents - infliximab, etanercept, adalimumab
First line treatment scalp psorasis
Potent topical corticosteroids OD for 4 weeks
Second line treatment scalp psoriasis
Alternative preparation of potent corticosteroid, e.g. shampoo or mousse, and/or topical agents to remove adherent scale (e.g. agents containing salicyclic acid, emollients, oils) before application of potent corticosteroid
Treatment for face, flexural, and genital psoriasis
Mild to moderate potency corticosteroid applied OD-BD max 2 weeks
SEs topical steroids
Skin strophy
Striae
Rebound symptoms
Examples of vitamin D analogues
Calcipotriol
Calcitriol
Tacalcitol
Advantages of vit D analogues
Adverse effects uncommon
Unlike corticosteroids can be used long term
Unlike coal toar and dithranol do not smell or stain
Disadvantage of vit D analogues
Tend to reduce scale and thickness of plaques but not erythema
Avoid in pregnancy
Adverse effects of dithranol
Burning and staining (wash off after 30 mins)M
Mild potency corticosteroid e.g.
HydrocortisoneM
Moderate potency corticosteroid e.g.
Clobetasone
Alclometasone
Hydrocortisone butyrate
Potent corticosteroid e.g.
Beclometasone
Betamethasone
Fluticasone
Mometasone
Very potent corticosteroid e.g.
Clobetasol
Appearance of actinic ketatoses
Small, crusty or scaly
Pink, red, brown, or same colour as skin
Rule of 9’s for burns
Each 9% SA:
- Head and neck
- Each arm
- Each anterior part of leg
- Each posterior part of leg
- Anterior chest
- Posterior chest
- Anterior abdomen
- Posterior abdomen
Criteria for referral to secondary care burns
- All deep dermal and full thickness burns
- Superficial dermal burns of more than 3% TBSA adults, 2% in children
- Superficial dermal burns involving face, hands, feet, perineum, genitalia, any flexure, circumferential burns limbs, torso, or neck
- Inhalation injury
- Electrical or chemical burn
- Suspicion of NAI
When are IV fluids required burns
Over 10% TBSA children, 15% in adults
Parkland formula
Volume of fluid = TBSA burn x weight (kg) x 4
Half fluid given in first 8 hours (from time of burn)
What is erythema multiforme
Hypersensitivity reaction
Features of erythema multiforme
- Target lesions
- Initially seen on back of hands/feet before spreading to torso
- Upper limbs > lower limbs