Dermatology Flashcards
SJS vs TEN?
SJS: <10% skin involvement
TEN: >30%
Aetiology SJS/TEN?
secondary to drug reaction (Never Press Skin As It Can Peel) NSAIDS Phenytoin Sulphonamides Allopurinol IVIG Carbamazepine Penicillin
S/S SJS/ten?
Scalded skin appearance over an extensive area
systemic upset
Ix SJS/TEN?
Nikolsky’s sign positive (epidermis separates with mild lateral pressure)
Mx SJS/TEN?
stop precipitating factor
ITU
IVIG
Immunosuppression (ciclosporin, cyclophosphamide) plasmapheresis
What is erythroderma?
any rash involving >95% of the body
causes of erythroderma?
eczema psoriasis drugs (gold) lymphoma, leukaemia idiopathic
complications of erythroderma
dehydration
high output cardiac failure
infection
what is seborrhoeic dermatitis?
chronic dermatitis caused by an inflammatory reaction related to a proliferation of a normal skin fungus (malassezia furfur)
who does seborrhoeaic dermatitis commonly affect?
immunosuppression (HIV)
Neurological (PD, Down’s, epilepsy)
Alcoholic pancreatitis
S/S of seborrhoeic dermatitis?
Eczematous lesions on sebum rich areas (dandruff, periorbital, auricular and nasolabial folds)
may present with otitis externa, blepharitis
Mx seborrhoeic dermatitis?
Scalp disease:
1st line: zinc pyrithione (‘head and shoulders’) and tar (‘neutrogena T/Gel’)
2nd line: ketoconazole
alternatives: selenium sulphide, topical corticosteroid
Face and body disease: topical antifungals (ketoconazole) topical steroids (short periods)
What is impetigo?
common skin infection caused by staph aureus, streptococcus pneumonia
S/S impetigo?
golden yellow crusted appearance
Management of impetigo?
hygiene meaures
Localised non-bulbous: topical H2O2 cream (peroxide), topical fusidic acid antibiotic
widespread non bullous; oral flucloxacillin OR topical fusidic acid 2% antibiotic
bullous systemically unwell: oral flucloxacillin
School exclusion until lesions crusted over OR 48 hour after Abx started
which bacterium causes acne vulgarisms?
increased sebum and blocked glands
propionibacterium acnes
20% of adolescents have moderate to severe acne
what are the levels of acne?
comedones (follicles impacted and distended by incompletely desquamated keratinocytes and sebum) - open or closed
papules and pustles
nodulocystic and scarring
S.S of acne vulgaris?
greasy face
comedones, papules, pustules, nodules
psychological impact, low self esteem
when do you do a dermatologist referral for acne?
nodulocystic acne/scarring severe form (acne conglobata, acne fulminano) severe psychological distress diagnostic uncertainty failing to respond to medications
Acne management?
Conservative:
- avoid over cleaning skin (2x day with gentle soap_
- use emollients and cleansers (non-comdeogenic)
- face : avoid picking and squeezing (scars)
meds:
Mild: 1st: topical retinoid and/or benzoyl peroxide +/-topical Abx /2nd line: azelaic acid
moderate: oral Abx (max 3m) + BPO + retinoid OR cocp + BPO/retinoid
severe: dermatologist referral - oral isotretinoin, once cleared maintain with topical retinoids or azelaic acid
Support; NHS choices leaflet, british association of dermatologists
Which Abx are preferred for acne?
topical: clindamycin 1%
oral: 1st line tetracyclines (lymecycline, doxycycline), 2nd line macrolides (erythromycin)
What are the S/S of acne rosacea?
1: flushing
2: asymmetrical rash of nose, cheeks, forehead and telangiectasia
3: persistent pustulopapular erythema (rhinopehyma, ocular involvement- blepharitis, photosensitivity)
commonly worsens with alcohol
Acne vulgaris vs acne rosacea?
vulgaris = young, comedones rosacea = middle-aged, flushing, symmetry
Management of acne rosacea?
mild/moderate: topical metronidazole
severe: oral tetracycline (oxytetracycline)
flushing, limited telangiectasia: topical brimonidine gel
adjuncts: high factor sunscreen, camouflage creams, laser therapy (telangiectasia)
What is hidradenitis suppurativa?
chronic inflammatory occlusion of folliculopilosebaceous units that obstructs the porcine glands and prevents keratinocytes from properly shedding from the follicular epithelium
RF for hidradenitis suppurativa?
FHx
obesity, DM, PCOS
Smoking
Mechanical skin stretching
S/s hidradenitis suppurativa?
recurrent build in intertriginous areas (axilla, neck, thights, inguinal)
coalesce of nodules can result in plaques, sinus tracts and rope like scarring
Management of hidradenitis suppurativa?
conservative: good hygiene and loose fitting clothing
smoking cessation
WL
medical:
acute - steroids,flucloxacillin +/- surgical incision and drainage
chronic - clindamycin (topical), lymecycline/clindamycin/rifampicin PO
What is pityriasis versicolor?
caused by malassezia furfur
common fungal infection that causes small patches of skin to become scaly and discoloured
What are the S/S of pityriasis versicolor?
trunk affected - hypopigmneted patches and scale, mild pruritic, follows a suntan
triggers for pityriasis versicolor?
immunosuppression, malnutrition, Cushing’s
Mx pityriasis versicolor?
topical ketoconazole
pityriasis versicolor vs vitiligo?
vitiligo affects peripheries and is much more confluent
what are the S/S of vitiligo?
well demarcated, depigmented skin patches
Vitiligo associations?
T1DM,Addisons, autoimmune thyroid, pernicious anaemia, alopecia areata
Mx vitiligo?
sunblock
camouflage makeup
topical corticosteroids (reverse changes if applied early)
what causes pityriasis rosea?
HHV-7
S/S of pityriasis rosea?
1: recent viral infection -> herald patch (usually on trunk)
2: erythematous oval scaly patches (running parallel to the line of Langer ‘fir tree appearance’)
Mx: self limiting (6-12w)
What are the types of psoriasis?
plaque
guttte
pustular
flexural
what are the features plaque psoriasis?
most common; well demarcated red, scaly patches affecting extensors
what are the features of guttate psoriasis?
streptococcal infection; multiple transient, red, teardrop lesions
no mx required
what are the features of pustular psoriasis?
palms and soles of feet
what are the features of flexural psoriasis?
skin is smooth in contrast to plaque psoriasis
Exacerbating factors for psoriasis?
trauma
ETOH
drugs (beta blockers, lithium, antimalarials, NSAIDs, ACEi, infliximab)
withdrawal of systemic steroids
infection (strep infection may trigger guttate psoriasis subtype only)
Management of chronic psoriasis plaque?
corticosteroids:
potent - use max 8w at a time
very potent - use max 4w at a time
4w breaks between courses of topical corticosteroids
SE: skin atrophy, striae, rebound symptoms
vitamin D analogue info
reduced scaling and thickness but no effect erythema
can be used long term
avoid in pregnancy
Management of psoriasis in primary care?
1st line (4w trial): OM corticosteroid (potent) and ON vitamin D analogue 2nd line (after 8 w): OM corticosteroid (potent) and BD vitamin D analogue 3rd line: BD corticosteroid (4w potent) or coal tar (OD or BD)
Adjunct: emollients (reduce scale loss, reduce pruritic)
Alternative: short acting dithranol (wash off after 30m)
Management of psoriasis in secondary care?
phototherapy (P-UVB, 3x/Week) or photochemotherapy (P-UVA + psoralen)
Systemic medications: 1st methotrexate; other: ciclosporin, retinoids, infliximab, etanercept, adalimumab
What is eczema?
chronic, relapsing, inflammatory skin condition characterised by an itchy red rash, commonly on FLEXURES
Eczema triggers?
irritants, contact allergens, extremes of temperature (worse in winter), abrasive fabrics, sweating
Signs & symptoms of eczema
infant: face and trunk
older child: extensors of limbs
young adult: localises to the flexures
Investigations eczema?
consider food allergies - blood or skin prick testing
consider contact dermatitis - patch testing
management of eczema?
flared - treat ASAP and for 24h post symptoms
What is the steroid ladder?
Help every busy dermatologist Hydrocortisone Euvomate (clobetason) Betnovate (betamethasone) (elocon - mometasone) Dermovate (clobetasol)
How is mild eczema managed?
emollients
mild potency topical steroids (hydrocortisone)
How is moderate eczema managed?
emollients
moderate potency topical corticosteroids
topical calcineurin inhibitors
bandages
How is severe eczema managed?
emollients potent topical corticosteroids systemic therapy phototherapy topical calcineurin inhibitors bandages
antihistamines (non sedating vs sedating at night)
How is infected eczema managed?
skin swab and culture oral flucloxacillin (erythromycin if pen allergic)
how is eczema herpeticum managed?
oral acyclovir
if around eyes same day referral to ophthal
health education (emergency = rapidly worsening eczema, clustered blisters, punched out erosions)
N.b. eczema herpeticum can look similar to impetigo so treat for both empirically with oral/IV Abx and oral/IV acyclovir
what are the directions for applying emollient?
apply to whole body and wait 30 mins before applying steroid creams
apply with Finger tip units (FTU)
What is 1 FTU?
Palm of hand
elbows
knees
give and example of a mild and moderate/severe calcineurin inhibitors?
mild/mod: pimecrolimus
mod/severe: tacrolimus
What is tinea?
fungal infection where dermatophyte fungi incase dead keratinous structure (trichophytum rubrum)
S/S of tinea?
ringed appearance +/- keri on (severe inflamed ringworm patch), red or silver rash
Tinea capitis - scalp
Tinea pedis - feet
Mx tinea?
Tinea capitis:
oral anti fungal (e.g. griseofulvin or terbinafine)
Other tinea:
mild: topical antifungals e.g. topical terbinafine, clotrimazole, miconazole
moderate: hydrocortisone 1% cream
severe: oral antifungals (1st line oral terbinafine, 2nd line: oral itraconazole
What advice should be given for managing tinea?
very contagious wear loose fitting cotton clothing dry throroughly after washing do not share towels no need for school exclusion wash affected areas of skin daily avoid scratching wash clothes and bed linen frequently
what is shingles?
Herpes zoster infection - reactivation of VZV
RFs for shingles?
Increasing age
Immunosuppression (HIV 15x more common, steroids, chemotherapy)
S/S shingles?
prodromal period (burning over affected dermatome for 2-3 days+/- fever, headache, lethargy rash (erythematous, macular rash over the affected dermatome - vesicular)
Management of shingles?
infectious until vesicles have crusted over
analgesia (paracetamol and NSAIDs), neuropathic agents, oral corticosteroids
Antivirals (PO acyclovir) (<72h, >50yo)
Complications of shingles?
- post-herpetic neuralgia (5-30% of patients depending on age)
- herpes zoster ophthalmicus
- herpes zoster optics (Ramsay-hunt syndrome)