Dermatology Flashcards
what is the pathophysiology of acne?
chronic inflammation +/- localised infection in pileosebaceous units within the skin. increased sebum preduction traps keratin and blocks the pulosebaceous unit leading to swelling and inflammation. Androgenic hormones increase production of sebum => increased in puberty
what are macules?
flat marks on skin
what are papules?
small lumps on skin
what are pustules?
small lumps with pus
what are comedones?
skin coloured papules due to blocked pilosebaceous units
what are blackheads?
open comedones with black pigmentation in the middle
what are ice pink scars?
small indentations that remain in skin after acne lesion heals
what are hypertrophic scars?
small lumps in skin that remain after acne lesions heal
what are rolling scars?
irregular wave like irregularies of the skin that remain after acne lesions heal
what acne medication if teratogenic?
retinoids
what is general advice for acne? 5
Avoid overwashing
Use non-alkaline synthetic detergent BD
Avoid oil based cosmetics and suncream
Avoid picking
Treatment may irritate skin initially
not enough evidence to support diets for acne
what are the 5, 1st line treatments for acne?
Topical benzoyl peroxide + Topical Adapalene, OD - Any severity
Topical Tretinoin + Topical Clindamycin, OD - Any severity
Topical Benzoyl peroxide + Topical clindamycin, OD - Mild-moderate
Topical adapalene + Topical benzoyl peroxide, OD + Oral lymecycline/doxycycline OD - moderate-severe
Topical azelaic acid BD + oral lymecycline/docycycline OD - moderate-severe
what contraceptive pill is best at reducing acne?
COCP (co-cyprindiol (Dianette)) - anti-androgenic effect
what is the last line option for acne (specialist)?
oral retinoids (isotretinoin (accutane))
what are 5 side effects of isotretinoin?
dry skin and lips
photosensitivity of skin
depression, anxiety, aggression, suicidal ideation
Stevens-johnson syndrome and toxic epidermal necrolysis
Sexual dysfunction
what is the name for head lice?
Pedicures hymns capitis
what are the 2 first line management options of head lice?
Wet combing - systematically removing head lice with comb
Dimeticone 4% lotion - left on for 8 hours then washed off - repeat after 7 days to kill hatchlings - physical insecticide
How long can it take for scabies infection to appear after initial infestation?
up to 8 weeks - usually begin in 3-6 weeks
what is the presentation of scabies? 4
Very itchy erythematous papules often excoriated with hemorrhagic crusts
Itching usually worse at night
Track marks where mites have burrowed - thin brown-grey line
Classically between finger webs but can affect whole body - usually spares back and head in adults
what is the management of scabbies?
Permethrin cream 5% - over 2 months old, to whole household
Applied all over body once weekly for 2 weeks, wash off after 8-12 hours
Also must wash all clothes and bedding on hot wash and hoover to destroy mites
How can scabies appear on genitals?
may be nodular even more itchy papules on genitals - usually indicative of sexually acquired scabies
what are Norwegian Scabies?
AKA Crusted scabies
In immunocompromised people
Mild/absent pruritus due to impaired immune response
Skin lesions generalised poorly defined erythematous fissured plaques covered by scales and crust - yellow-brown veracious aspect on bony prominences
need to be isolated
what are 2 tests that can be used to confirm scabies?
Ink burrow test - ink applied to suspect papule then wiped off with alcohol to remove surface ink - ink runs down burrow creating zigzag line
Microscopy of skin scrapings
what is the management of difficult to treat or Norwegian scabies?
Oral Ivermectin 200 micrograms/kg usually one dose, may be repeated a week later
what can be used to ease the itching from scabies?
Crotamiton crean and chlorphenamine
what is the name of the mite that causes scabies?
Sarcoptes Scabiei
what are 6 risk factors for scabies?
close living conditions
poor hygiene practices
socioeconomic factors
immunocompromised state
institutional settings
geographical distribution - higher in tropical regions
How long can pruritus continue after clearance of scabies?
4-6 weeks
what is folliculitis?
inflammation of the hair follicles
causes papules, pustules or nodules surrounding hair follicles
what are 4 infective causes of folliculitis?
Staph aureus
Pseudomonas aeruginosa
Candida
HSV
what are 3 non-infective causes of folliculitis?
dermatological - acne, hidradenitis suppurativa, epidermal cysts
Mechanical factors - tight clothes, shaving, plucking
Occlusive topical products - heavy creams, cosmetics, blocking hair follicles
what are 4 risk factors for folliculitis?
Immunosuppression
chronic diseases - impaired immunity and skin barrier
Obesity - increased skin folds
Prolonged Abx use - alters normal skin flora
what are 4 clinical features of folliculitis?
Erythematous papules and pustules
pruritus
pain
Folliculr hyperkeratosis - rough thick skin around hair follicle
what are 4 variations of folliculitis?
pseudofolliculitis barbae - beard bumps in men with curly hair
Hot tup folliculitis - sudden onset widespread
Eosinophilic folliculitis - in immunocompromised - intensely itchy pustules predominantly on upper body
Folliculitis decal vans - chronic deep folliculitis leading to scaring and permanent hair loss
what is the management of folliculitis?
conservative - hygiene, warm compress, avoid hair removal in area
Topical
- antiseptics - chlorhexidine
- antibiotics - fusidic acid
- antifungals - ketoconazole
Systemic Flucloxacillin if severe or recurrent
what are 6 complications of folliculitis?
Recurrent/chronic folliculitis
furuncles (boils) or carbuncles - deeper infection
Abscess
Sycosis barbae - scaring and hair loss in beard
Infection/sepsis
Post strep glomerulonephritis
what is the only 1st line acne management that can be used during pregnancy/breast feeding?
Topical benzoyl peroxide + topical clindamycin
How long to review 1st line acne management?
review after 12 weeks
if fails:
mild-mod - try another
moderate-severe - +Abx if prev treatment didn’t have them
Severe - if prev included abx - refer to derm
what are 6 complications of acne?
Scarring
Nodulocystic lesions
secondary infections
Hyperpigmentation
Post inflammation erythema
Psychological complications - anxiety, depression, social withdrawal, suicidal ideation
what are 3 complications of acne treatment?
Abx resistance
Tetracycline staining - staining to teeth if used in children and pregnant women
Isotretinoin side effects
what is the most common type of cancer in the west?
basal cell carcinoma
what are 4 features of basal cell carcinoma?
slow growth and local invasion
in sun-exposed sites - head and neck usually
pearly/flesh coloured papule with telangiectasia and rolled edge
may have ulcerated central crater
https://docs.google.com/document/d/1OTYukCgnWzNJWKFq39WzxtylmSEFxB-0RB5AD-IM71k/edit
what are 6 risk factors for basal cell carcinoma?
Male
UV exposure
Fair skin - Fitzpatrick I/II
Xeroderma pigemtosum
Immunosuppression
Arsenic exposure
what are 5 management options for BCC?
surgical removal or Mohs surgery
curettage
cryotherapy
topical cream - imiquimod , fluorouracil
radiotherapy
what are 2 medications for BCC?
Imiquimod
Fluorouracil
what 2 pathogen cause impetigo?
staph aureus - most common
strep pyogenes
what is the characteristic sign of impetigo?
golden crusted rash/skin infection
https://docs.google.com/document/d/1qoy21wpl4IiMomdMZYuv3hWnrli6vTGbrQIFKhZ3uJQ/edit
what are the two different types of impetigo?
bullous - 1-2cm fluid filled vesicles which grow and burst to form golden crusts. may be itchy
non-bullous - golden crusts
what is the cause of bullous impetigo?
always staph aureus
produces epidermolytic toxins that break down proteins and hold skin cells together causing fluid filled vesicles to form on skin
what is the management of non-bullous impetigo in children and adults? 3
1st line - hydrogen peroxide cream 1%, BD/TDS for 5 days
2nd - If unsuitable - topical fusidic acid 2% TDS
OR if fuscidic acid resistance - Mupirocin 2% TDS 5 days
3rd - oral flucloxacillin - when more widespread/unwell
what is the name of severe bullous impetigo?
staphylococcus scalded skin syndrome
what is the management of bullous impetigo?
abx - usually flucloxacillin
what are 6 complications of impetigo?
cellulitis
sepsis
scarring
post-streptococcal glomerulonephritis
staphylococcus scalded skin syndrome
scarlet fever
Can children go to school with impetigo?
Not until lesions are crusted and healed or 48 hours after starting Abx
what is the dose of flucloxacillin in adults for impetigo?
500mg QDS for 5 days
what abx is used in penicillin allergy in impetigo and what is the dose in adults?
Clarithromycin 250mg BD 5 days
IN PREGNANCY
Erythromycin 250mg-500mg QDS
what are the 2 different types of contact dermatitis/?
irritant - more common, due to exposure to damaging substances
Allergic - commonly due to nickel, fragrances, rubber accelerators and preservatives
Can also have mixed picture
what are the 3 layers of the skin?
epidermis
dermis
hypodermis
what are the 5 layers of the epidermis? mnemonic
Come Lets Get Sun Burnt - top to bottom
Stratum Corneum
Stratum Lucidum
Stratum Granulosum
Stratum Spinosum
Stratum Basalae
What are 3 variants of contact dermatitis?
phototoxic ad photoallergic contact dermatitis
Sysetemic contact dermatitis
Pigmented contact dermatitis
what does contact dermatitis look like?
Erythema, vesicles and bulae, oedema and puritus - in acute phase
Lichenification, fissuring and hypo/hyperpigmentation - in chronic phase
https://docs.google.com/document/d/1ajjHdB60SsDgKx_ZVqD6-o80DAZ2ZMwgWxdrzLKv5zw/edit
what are 3 ways to investigate contact dermatitis?
Patch testing
Skin biopsy - differential for psoriasis or T-cell lymphoma
Lab tests - ??underlying HIV/hep C
that is the management of contact dermatitis?
Identification and avoidance of trigger
Symptomatic Tx - ~Topical steroids, emollients
Referral to derm if symptoms persist
what are 4 complications of contact dermatitis?
secondary infections - impetigo, cellulitis
Chronic skin changes - lichenification, hypo/hyperpigmentation
Mental health
Sensitivity spread - allergic contact dermatitis spreading to wider allergic reactions
what virus causes cutaneous warts?
HPV
what are 5 risk factors for cutaneous warts?
Age - most common in children and young adults
Impaired immunity
Skin integrity
Contact with infected individuals
Environmental factors - moist environments, communal showers
what cells does HPV invade in the formation of cutaneous warts?
keratinocytes
what are 6 different types of cutaneous warts?
common warts - verruca vulgaris
Flat warts - verruca plana
Filiform warts
Palntar warts - verruca plantaris
Mosaic warts
Anogenital warts - condyloma acuminatum
what are the features of common warts?
firm, hyperkerototic papules or nodules with roughened surface - commonly found on hands, can be anywhere
what are the features of flat warts?
small, smooth, flat toped papules
often appear in large numbers
most common on face, dorm of hands and shins
what are features of filiform warts?
predominantly on face, lips and eyelids
threadlike or fingerlike in appearance, may have a stalk
what are plantar warts?
located on soles or feet or weight bearing areas
Flat appearance with central black speck
what are mosaic warts?
when plantar wats coalesce together to form a large plaque with a mosaic pattern
what are anogenital warts?
occur in anogenital region
appearance ranging from small smooth papules to large cauliflower like masses
what is the 1st line management of cutaneous warts?
Salicylic acid daily for up to 12 weeks
OR
Cryotherapy - every 2 weeks for up to 6 treatments
what advice should be given to people with warts?
Generally go away on own
Contagious but low risk of transmission
Avoid scratching to reduce personal spread
what are 5 cutaneous wart treatment options in secondary care?
physical ablation
Antimitotic treatment - podophyllotoxin, retinoids
Immunomodulatory therapy - imiquimod 5%
Virucidal Tx - formaldehyde and glutaraldehyde
Cantharidin
what is nappy rash?
contact dermatitis in the nappy area usually caused by friction and contact with urine and faeces in a dirty nappy
when is nappy rash most common?
between 9-12 months
what are 3 forms of rare severe nappy rash?
jacquet’s erosive diaper dermatitis - punch out ulcers/erosions with elevated borders
Peianal pseudoverrucous papules and nodules
Granuloma gluteal infant - 0.5-4cm large cherry red plaques and nodules, asymptomatic
How long does it take nappy rash to resolve?
within 1 week
can take up to 21 days with candida infection also
what are 6 risk factors for nappy rash?
delay in changing
iritant products and vigorous cleaning
Poorly absorbant nappies
diarrhoea
oral antibiotics - predispose candida
Pre-term infants
what is the presentation of nappy rash?
sore, red inflamed skin in nappy areas
Individual patches on exposure areas that come into contact with nappy
Spares folds
If severe may lead to erosions and ulcerations
what are 5 signs that indicate candida infection over nappy rash?
rash extending into skin folds
large red macules
well demarcated scaly border
circular pattern of rash spreading outwards
satellite lesions
what is the management of uncomplicated nappy rash?
Switch to higher absorbency nappy - disposable Gel matrix
Change and clean skin after soiling
Use water or alcohol free products for cleaning area
ensure nappy area dry before replacing nappy
maximise nappy free time
what is the management of inflamed nappy rash?
apply barrier treatment - soft paraffin ointment, zinc or caster oil ointment
Consider 1% hydrocortisone >1month old
what is given for nappy rash + suspected candida?
Clotrimazole 1%
Econazole 1%
miconazole 2%
what is given for nappy rash + bacterial infection suspected?
Oral flucloxacillin 7 days QDS
- 1 month-1year = 62.5-125mg
- 2-9 years = 125-250mg
IN ALLERGY - Clarithromycin - dose based off weight
what are the most common pathogen for cutaneous fungal infections?
Tichophyton
what are 5 risk factors for fungal skin infection?
Hot, humid climates or high temperatures
Tight fitting clothing
Obesity
Hyperhidrosis
Immunocompromised states
what are 4 complications of cutaneous fungal infection?
Secondary bacterial infection
Majocchi granuloma formation - dermatophte invades via hair follicle and penetrates deeper into skin
Fungal infection of the hand - tinea manuum
Tinea Incognito - due to inappropriate use of topical corticosteroids leads to changes in appearance of lesions
what are the different names of fungal infection in different parts of the body?
tinea pedis - athletes foot
tinea capitis - ringworm of scalp
tinea cruis - groin
tinea coporis - body
onchomycosis - nail
what does cutaneous fungal infection look like?
Single or multiple red/pink flat or slightly raised ring shape lesion with scaly advancing edge and clear central area
May have accumulated scales and have white/yellow curd like substance over infected area - if candida
Itchy
https://docs.google.com/document/d/1eHz4s6_7lqU8QmEmr7Fj-5giV8Ro4sg9LHW18YYMBP8/edit
what is a Kerion?
an abscess causes by a fungal infection most often caused by tinea capitis - causes boggy pus filled lump on scalp with localised alopecia
what is the 1st line management of mild-moderate cutaneous fungal infection?
Terbinafine 1% - >12 years - apply OD/BD for 1-2 weeks
CLotrimazole 1% - 2-3x a day for 4 weeks
Miconazole 2% - BD 10 days
Econazole 1% - BD till healed
what is the management of severe cutaneous fungal infection (tinea)?
Oral antifungals
1 - Terbinafine PO 250mg BD for 4 weeks
Itraconazol or griseofulvin if terbinafine contraindicated
what are 2 contraindications and 3 cautions to prescribing oral terbinafine?
Contraindications
- hepatic impairment
- severe renal impairment
Cautions
- autoimmune disease - risk of lupus like effect
- psoriasis - increases risk of exacerbation
- renal impairment - if eGFR <50, half dose
when can topical steroid be prescribed in cutaneous fungal infection?
if especially inflamed or itchy prescribe 1% hydrocortisone
what is the management of severe cutaneous candida infection?
Oral FLuconazole 50mg PO OD for 2 weeks
what are 3 contraindication to fluconazole?
acute porphyria
pregnancy
drug interactions - erythromycin, pimozide, quetiapine
what are 3 instances where fluconazole should be prescribed with caution?
Risk of QT prolongation - cardiomyopathy, sinus Brady, arrhythmia, hypokalaemia etc…
Hepatic impairment
Renal impairment <50 eGFR
what is the presentation of fungal scalp infection?
scaling and itching of scalp, may have circular patches of hair loss and erythema with scattered crusting pustules
what is the management of fungal scalp infection?
1 - Oral griseofulvin - 1000mg OD for 4-8 weeks - for adults
+ Ketoconazole shampoo 2x weekly for 2-4 weeks
what are 3 different types of fugal foot infections?
interdigital
moccasin/dry type - more diffuse, chronic presentation causing scaling an derythema
Vesicobullous type - vesicles and bullae
what is the appearance of fungal nail infection?
Superficial white small flaky patches and pit son top of nail
Begins distally and spreads to nail plate
White or yellow opaque streaks along one side of nail
Sublingual hyperkeratosis
what is the management of fungal nail?
1 - amorolfine 5% nail lacquer 2x weekly for 9-12 months
2 - oral terbinafine 250mg OD for 6 weeks /itraconazole 200mg BD for 1 week then repeat after 21 days
what is the pathophysiology of urticaria?
caused by release of histamine and por-inflammatory chemicals by mast cells
may be part of allergic reaction or autoimmune reaction
what are 6 causes of acute urticaria?
Allergies
Contact with chemicals. latex, stinging nettles
medications
Viral infections
insect bites
dermatographism
what is chronic idiopathic urticaria?
describes recurrent episodes of chronic urticaria without a clear trigger
what is chronic inducible urticaria?
chronic urticaria inducible by certain triggers
sunlights
temperature change
exercise
strong emotion
hot or cold weather
pressure
what is autoimmune urticaria?
chronic urticaria associated with underlying autoimmune conditions such as SLE
what is the management of urticaria?
1 - Non-sedating antihistamines
- Certirizine, fexofenadine or loratadine - can consider up to 4x licensed dose
if severe short course of steroids for 7 days
Leukotriene receptor antagonist - montelukast or leukotriene receptor antagonist
what classes as chronic urticaria?
> 6 weeks
what score can be used to assess severity of urticaria?
urticaria activity score - UAS7
what are 4 subtypes of psoriasis?
plaque psoriasis
flexural psoriasis
guttate psoriasis
pustular psoriasis
what are 4 nail changes in psoriasis?
pitting
oncholysis
sublingual hyperkeratosis
loss of nail
dactylisis - sausage fingers
what infection often triggers guttate psoriasis?
streptococcal infection 2-4 weeks prior
what are 4 medications know to trigger psoriasis?
Lithium
beta blockers
antimalarials
NSAIDs
What is the pathophysiology of psoriasis?
abnormal activation of T cells leading to keratinocyte hyperproliferation
what is plaque psoriasis (psoriasis vulgaris)?
well-demarcated erythematous plaques with silvery scales typically located on elbows, knees, scalp and lower back
https://docs.google.com/document/d/1IKNTFez0ZKzcx5rMylEo3n6XHePlfhvkTvgDyIsUmhY/edit?tab=t.0
what is guttate psoriasis?
small, raindrop-sized lesions often occurring after a streptococcal pharyngitis infection in children and young adults
https://docs.google.com/document/d/1rmtC2AwmgjuLYXW9lu3SSoX4uGJj4hZhGJZJFcFhNUY/edit?tab=t.0
what is flexural psoriasis?
variant is seen in skin folds such as axillae, inguinal region and under breasts. Lesions are smooth, shiny and lack scales due to moisture in these areas
what is pustular psoriasis?
Localised or generalised sterile pustules on an erythematous base.
Palmoplantar pustulosis (localised to hands and feet)
Generalised pustular psoriasis which can be life-threatening requiring immediate medical intervention
what is erythrodermic psoriasis?
severe inflammatory form leading to widespread erythema covering almost the entire body surface area - skin comes away in large patches. This type can be potentially life-threatening due to high risk of infection and fluid loss
what are 5 signs of psoriasis?
plaques - raised ret patches covered in silvery white dead skin cells or scales
Nail changes
Auspitz sign - removal of scales causes pinpoint bleeding due to ruptures in dermis
Koebner phenomenon - new psoriatic plaques form at sign of skin injury or trauma
residual pigmentation
what is the management of mild to moderate plaque psoriasis?
1a - emollients
1b - topical corticosteroid + vitamin d analogues (calcipotriol)
2 - coal tar preparations, dithranol
what are some options for the management of severe/unresponsive psoriasis?
1 - narrow band UVB phototherapy
2 - Non-biological therapies - methotrexate, ciclosporin, acitreitin
3 - Biological therapies
what are the names of two combo vitamin d analogue and steroid preparations prescribed by a specialist?
dovobet
enstilar
what 3 conditions does psoriasis increase the risk of?
cardiovascular disease - assess Qrisk every 5 years
Psoriatic arthritis
mental health issues
how long does it take the lesions to resolve in guttate psoriasis?
2-3 months
what are the 3 key clinical features of pityriasis rosea?
large oval ‘herald’ patch on trunk 2 weeks before rest of plaques
itchy rash
erythematous oval papular scaly patches on trunk and extremities in fir tree pattern
what is the presentation of molluscum contagiosum?
pink/pearly white papule with central umbilication up to 5mm
https://docs.google.com/document/d/1P17Nkki4zqHr3LvtD0-fZgdLeRC-nq6PRSqAqBE5WgM/edit?tab=t.0
what are3 conditions which can lead to arterial ulcers?
Peripheral arterial disease
Diabetes Mellitus
Rheumatoid Arthritis - due to vasculitis
what are 5 non-medical risk factors for arterial ulcers?
Smoking
poor nutrition - impaired wound healing
Older age
Obesity
Immobility
what are 8 features of arterial ulcers?
Distal, affecting toes or dorsum of foot
PAD symptoms
Smaller and deeper than venous
Well defined borders
Punched out appearance
Pale
Less likely to bleed
Painful - worse when lying horizontally and on elevation
what are 8 features of venous ulcers?
In gaiter areas - between top of foot and bottom of calf muscle
Chronic venous changes - hyperpigmentation, venous eczema, haemosiderosis, lipodermatosclerosis
Often after minor injury
More superficial
irregular sloping borders
more likely to bleed
Less painful, relieved by elevation
where do arterial ulcers usually occur?
pressure area - toes, heels, lateral malleoli
what are 4 investigations for ulcers?
Ankle brachial plexus index
Doppler USS
MRA or CTA
Tissue biopsy and charcoal swabs
what is the management of arterial ulcers?
Revascularisation surgery - if ABPI <0.8
Wound care - maintain moist wound environment, hydrocolloids, hydrogels, foam dressings
Pain management
Lifestyle modification
what are 5 complications of arterial ulcers?
Infection
gangrene
limb amputation
sepsis
pain
what is the pathophysiology of venous ulcers?
Chronic venous insufficiency leads to venous hypotension and increased capillary pressure leading fluid and blood cells to leak into interstitial space. This leads to local hypoxia, inflammation, skin and subcutaneous tissue damage
what is the management of venous ulcers?
Would cleaning, debridement, dressing
Compassion therapy (after arterial disease ruled out with ABPI) - 4 layer compression
Pentoxifylline - orally - not licenced
ABx and analgesia
r/f to vascular, derm, tissue viability, pain, diabetes depending
what is a stage one pressure ulcer?
non-blanching erythema, may be warm and darkly pigmented
what is stage 3 pressure ulcer?
full thickness - with loss of subcutaneous fat some f which may still be visible. May slough
what is a stage 2 pressure ulcer?
partial thickness with loss of dermis presenting as shallow open ulcer
what is stage 4 pressure ulcer?
full thickness and affecting bone/tendon/muscle which is visible/palpable, may slough
what scoring system is used for risk of pressure ulcers?
Waterlow score
what are 4 risk factors or pressure ulcers/
malnourishment
incontinence - urinary or faecal
lack of mobility
significant cognitive impairment
what is the management of pressure ulcers?
moist wound environment - hydrocolloid dressings and hydrogels
Tissue viability nurse
what are 6 risk factors for cellulitis?
Venous insufficiency and PAD
Skin breaks + conditions that disrupt dermis
T2DM
Immunocompromised
Obesity
Pregnancy
what is the most common pathogen causing cellulitis?
1 - Strep pyogenes
also other group A beta haemolytic strep
2 - Staph Aureus
what are 4 complications of cellulitis?
Necrotising fasciitis + myositis
Sepsis
Subcutaneous abscess
what are the clinical features of cellulitis?
Swelling, erythema, warmth, tenderness
fever, malaise, nausea
what classification is used for cellulitis?
Eron classification
what is Eron 1?
For cellulitis
no sign of systemic toxicity, no co-morbidities
what is eron 2?
cellulitis
systemically unwell or well but with co-morbidities - PAD, venous insufficiency, morbid obesity
what is eron 3?
for cellulitis
significant systemic upset - acute confusion, tachycardia/pnoea, hypotension
what is eron 4?
for cellulitis
sepsis or necrotising fasciitis
what is the 1st line management of cellulitis in adults?
Flucloxacillin 500-1000mg QDS 5-7 days
ALLERGY - Clarithromycin 500mg BD, Doxycycline 200mg day 1 then 100mg OD
Pregnancy + Allergy - Erythromycin 500mg QDS
5-7 days
when should IV Abx be given in cellulitis?
Eron III or IV
Severe dapidly deteriorating cellulitis
very young or very old
immunocompromised
significant lymphoedema
what is the 1st line abx in cellulitis near eyes or nose?
Co-amoxiclav 500/125mg TDS for 7 days
ALLERGY - Clarithromycin 500mg BD + Metronidazole 400mg TDS
mutations in what gene can cause increased risk of eczema?
Filaggrin genes (FLG)
what is the most common cause of necrotising fasciitis?
streptococcus pyogenes
what are 7 risk factors for necrotising fasciitis?
recent trauma, burn or skin infection
advancing age
immunosuppression
diabetes
SGLT-2 inhibitors
Marine exposure
close contact with others with nec fasc
what is the clinical presentation of necrotising fasciitis?
early - intense pain, skin puncture injury, flu like symptoms, erythema, hypersensitive skin
Late - subcutaneous emphysema, skin necrosis (blue, white, dark, mottled), fever, reduced sensation, hypotension, tachycardia
what is the management of necrotising fasciitis?
Immediate surgical debridement
IV Abx - broad spectrum - Iv fluclox, benpen, metronidazole, clindamycin, gent
Supportive care - aggressive fluids
Amputation
what are the 2 growth phases of melanomas?
Radical - growth in the epidermis
vertical - growth downwards into the dermis - more likely to lead to metastasis
what are 9 risk factors for melanoma?
Increasing age
FHx
Pale skin - fitzpatrick I/II
Red/blonde/light hair
UV exposure
Precursor lesions - dysplastic naevi
Previous skin cancers
immunosuppression
xeroderma pigmentosum - autosomal recessive condition
How do you assess a possible melanoma?
ABCDE
Asymmetry of lesion
Border irregularities
Colour - non-uniform
Diameter >6mm
Evolution - shape, size, colour
what is the most common type of melanoma?
Superficial spreading
what are the 5 different types of melanoma?
superficial spreading
nodular
lentigo maligna
acral lentiginous
amelanotic
what is a superficial spreading melanoma?
Flat pigmented lesion with asymmetrical or irregular borders
Horizontal growth
Sun exposed areas
what is a nodular melanoma?
2nd most common
Red/brown nodule that may ulcerate/bleed easily
Vertical growth
sun exposed areas
what is lentigo maligna melanoma?
irregularly shaped macule
slow horizontal growth
seen in elderly
common on face
what is acral lentiginous melanoma?
palms, soles, nail bed
Hutchinson sign - dark linear subunggual patch
more common in darker skin
not related to UV exposure
what is an amelanotic melanoma?
pink nodule lacking pigmentation
what are the major and minor criteria for melanoma referral and what score means increased suspicion?
> 3 points
Major +2 point
- Change in size
- irregular shape/border
- Irregular colour
Minor +1 point
- largest diameter >7mm
- inflammation
- oozing or crusting of lesion
- change in sensation - including itch
What is the investigation for melanoma?
dermoscopy
Excision biopsy
CT TAP for staging
what is the management for early stage melanoma?
Excision
topical iquimod
stage 0-II
what is the management of advanced stage melanoma?
stage III
Lymph node dissection or lymphadenectomy
Radiotherapy
Resection of mets
what is the management of late stage melanoma?
systemic tx - BRAF inhibitors, immunotherapy, chemo
radiotherapy
resection of mets
where does melanoma spread to?
Lymph nodes
Brain
Bone
Liver
Lung
GI tract
what is actinic keratosis?
dysplastic epidermal lesions which are usually precursors to cutaneous squamous cell carcinomas
what is the pathophysiology of actinic keratosis?
UVB radiation mutates p53 gene in DNA of keratinocytes preventing apoptosis and causing keratinocytes to undergo clonal expansion
what are 6 risk factors for actinic keratosis?
Chronic UVB exposure
Pale skin
Male
Xeroderma pigmentosum
Immunosuppression
Increasing age
what is the presentation of actinic keratosis?
Usually pink with yellow tinge
Rough scaly macule or papule
1-5mm
irregularly shaped
on sun exposed areas
what is the management of actinic keratosis?
Cyotherapy
Curettage
excision
Topical therapy - fluorouracil, iquimod, diclofenac
what are 6 complications of actinic keratosis?
pruritus
bleeding
progression to invasive squamous cell carcinoma
scaring
hypopigmentation
transient irritation
what is another name for cutaneous squamous cell carcinoma in situ?
Bowen’s disease
what is the second most common type of skin cancer?
squamous cell carcinoma
what are 5 risk factors for squamous cell carcinoma?
Sun exposure and Hx of sunburn
use of tanning beds
chronic skin inflammation or injury
HPV
Immunosuppression
what are 3 types of invasive squamous cell carcinoma?
cutaneous horn - produced by excess keratin production
Marjolin ulcer - develops with scar or ulcer
Keratoacanthoma
what are 5 presentations of squamous cell carcinoma?
itchy tender or painful lesions
ulcerating lesions
UV exposed areas
Scaly or erythematous lesions
irregular borders
what is the investigation for squamous cell carcinoma?
Dermoscopy
Skin biopsy
CT TAP for staging
what is the management of squamous cell carcinoma?
Surgical excision - wide local (4/6mm margins) or Moh’s surgery
Aggressive cryotherapy
Radiotherapy
Topical 5-fluorouracil - in situ
Imiquimod - in situ
what are 4 complications of squamous cell carcinoma?
Local recurrence
mets
nerve involvement - perineural invasion
Radiation dermatitis
what is erythema multifome?
erythematous rash caused by hypersensitivity reaction
Associated with viral infection, medications, HSV and mycoplasma pneumonia
what pneumonia is associated with erythema multiforme?
mycoplasma pneumoniae
what pneumonia is associated with erythema multiforme?
mycoplasma pneumoniae pneumonia
what is the presentation of erythema multiforme?
widespread itchy erythematous rash
Target lesions - red rings within larger red rings, darkest at the centre like a bullseye
Can appear anywhere on body, usually on palms and soles
Not on oral mucosa but can cause sore mouth (stomatitis)
https://docs.google.com/document/d/1wyVi10pgtM5EjQn2xPFkyTGvRLXTB_heTU-tvWeUmec/edit?tab=t.0
where is eczema usually found?
flexor surfaces
what is the pathophysiology of eczema?
there are defects in the skin barrier allowing entrance of microbes, irritants and allergens which leads to immune response
what is the most significant genetic risk factor for eczema?
mutations in Filaggrin gene
what ae 6 features of eczema?
Itch
Erythema
Skin lesions
Dry skin
Lichen simplex chronicus - thick hyperpigmented skin over chronic lesions
Distribution - flexor surfaces, hands, face, trunk
what is the diagnostic criteria for eczema?
An itchy skin condition in last 12 months
+ 3 of
- onset <2 years
- Hx of flexural involvement
- Hx of generally dry skin
- PHx of atopy
- Visible flexural dermatitis
How is eczema managed not in a flare?
emollients and trigger avoidance
what is the management of eczema flares?
Thicker emollients
Topical steroids
Wet wrapping
IV ABx and oral steroids if very severe
what are 4 specialist treatments for eczema?
Zinc impregnated bandages
Topical tacrolimus
Phototherapy
Systemic immunosuppression
what are 3 thin emollients?
E45
Diprobase cream
Aveeno cream
what are 3 thick emollients?
50:50 ointment
Hydromol ointment
Diprobase ointment
what is the steroid cream ladder?
mild - hydrocortisone 0.5,1,2.5%
moderate - eumovate (clobetasol butyrate) 0.05%
potent - betamethasone 0.1%
very potent - clobetasol propionate 0.05%
how should emollients and topical steroids be administered in relation to each other?
Emollients
wait 30 mins
Topical steroids
what is the most common bacterial infection in eczema?
s aureus
what abx can be used to treat bacterial infection of eczema?
Topical fusidic acid 2% 5-7 days
Oral flucloxacillin 500g QDS - 5-7 days
PEN ALLERGY - Oral Clarithromycin 250mg BD
what are 3 complications of eczema?
Skin infection
eye complications - blepharitis and conjunctivitis more common
Psychosocial impact
what is eczema herpeticum?
viral skin infection caused by HSV-1 most commonly or varicella zoster
what is the presentation of eczema herpeticum?
eczema sufferer develops a rapidly progressing widespread painful vesicular rash with monomorphic punched out erosions 1-3mm
Also has fever, lethargy, irritability, reduced oral intake and swollen lymph nodes
What is the management of eczema herpeticum?
Aciclovir - 10-14 days
Ganciclovir for ocular involvement
what is seborrhoeic keratosis?
Common benign proliferation of keratinocytes associated with increasing age and UV exposure
what is the appearance of seborrhoeic keratosis?
Warty skin lesions
Stuck on appearance
Usually multiple lesions
Usually brown but can range in colour
https://docs.google.com/document/d/1S_oYGYEw8lfWvzg4M3tNOvjA3A8GOESySV58HMXSIJU/edit?tab=t.0
what is the management of troublesome seborrhoeic keratosis?
Curettage
cryotherapy
shave biopsy
ablative laser therapy
what is Seborrhoeic dermatitis?
inflammatory condition of sebaceous glands causing erythema, dermatitis and crusted dry skin
what is the medical name for cradle cap?
Seborrhoeic dermatitis
what pathogenic colonisation is thought to play a role in Seborrhoeic dermatitis?
Malassezia yeast (furfur)
what is the presentation of Seborrhoeic dermatitis?
Eczematous lesions on sebum rich areas - scalp, periorbital, auricular, nasolabial folds, back
Dandruff
Itching
Yellow or white scales
Erythematous greasy patches
Otitis externa and blepharitis may develop
https://docs.google.com/document/d/1ELUMg7_KGEmSYtllmztjzfBfZyDQ8RwUDoCXq1R1tqs/edit?tab=t.0
what are 2 conditions associated with Seborrhoeic dermatitis?
Parkinsons
HIV
what is the management of Scalp Seborrhoeic dermatitis?
1 - Ketoconazole 2% shampoo
OTC - Zinc pyrithione (head and shoulders), Tar (neutrogena t/gel)
Selenium sulphide and topical corticosteroids
what is the managing of face and body Seborrhoeic dermatitis?
1 - Ketoconazole
2 - Clotrimazole or miconazole
topical steroids
what is the management of cradle cap?
1 - Baby oil/oil and gentle brushing of scalp then washing off crusts
2 - whit petroleum jelly overnight then washing off crusts in morning
3 - Clotrimazole, miconazole
what are 7 features of rosacea?
Affects nose, cheeks and forehead
Flushing often 1st symptom
Telangiectasia are common
Later persistent erythema, papules and pustules
Rhinophyma - thickened enlarge glands of nose
Blepharitis
Sunlight may exacerbate
https://docs.google.com/document/d/1TfJnT9_kR9LoAg-pURh0_k8g1XTQaiSWZn9dvjsFJc0/edit?tab=t.0
what is the management of rosacea?
Prevention of flares - High factor sun cream
Topical brimonidine gel - reduces redness within 30 mins
Topical ivermectin - for papules/pustules
Severe papules/pustules = topical ivermectin PLUS oral doxycycline
Extensive telangiectasia - laser therapy
what is stevens-johnson syndrome and toxic epidermal necrosis?
a disproportionate immune response causing epidermal necrosis resulting in blistering and shedding of top layer of skin
SJS <10% of body
TEN >10% of body
what are 6 medications that can cause stevens-johnson syndrome?
anti-epileptics(lamotrigine, carbamazepine, phenytoin)
antibiotics - sulphonamides, penicillins
allopurinol
NSAIDs
COCP
what are 7 infections that can cause stevens-johnson syndrome?
herpes
HIV
Mumps
FLu
EBV
mycoplasma pneumonia
CMV
what is the natural history of stevens-johnson syndrome?
starts with fever, cough, sore throat, mouth, eyes and skin
then develop purple/red rash which blisters
the after a few days skin sheds leaving raw tissue underneath
can also affect internal organs
what sign is positive in SJS/TEN?
Nikolsky sign - erythematous areas are rubbed gently and blisters and erosions appear where epidermis has separated
what is the management of stevens-johnson syndrome?
admit to derm/burns unit
steroids
IVIG
Immunosuppression - ciclosporin, cyclophosphamide
what are 4 complications of SJS/TEN?
secondary infection
permanent skin damage and scarring
visual complications with eye involvement
dehydration and electrolyte disturbance
what is Pyoderma gangrenosum?
Rare non-infectious inflammatory disorder of painful skin ulceration most commonly in lower legs
what is the pathophysiology of Pyoderma gangrenosum?
neutrophilic dermatosis - dense infiltration of neutrophils in affected tissue
what are 6 risk factors for Pyoderma gangrenosum?
Idiopathic
IBD
Rheumatological - SLE, RhA
Haematological
Granulomatosis with polyangiitis
Primary biliary cirrhosis
what is the presentation of Pyoderma gangrenosum?
small pustule, red bump or blood blister where skin breaks down to a deep necrotic ulcer with a purple edge
what is the management of Pyoderma gangrenosum?
1 - oral steroids
Immunosuppression
what is alopecia areata?
an autoimmune skin condition resulting in inflammation of the hair follicle leading to non-scarring hair loss on scalp and body and broken exclamation mark hairs at the borders
what are the 3 different types of alopecia arata?
patchy alopecia areata
alopecia areata totalis - total loss of scalp hair
Alopecia areata universalis
what is the conservative management of alopecia areata?
no treatment - spontaneous remission in 80% in 1 year
Cosmetic camouflage
Psychological support
what is the medical management of alopeica areata?
topical steroids - clobetasol propionate 0.05%
intralesional corticosteoids systemic corticosteroids
topical minoxidil
topical immunotherapy
what are 5 risk factors for male androgenic alopecia?
Fhx
alcohol consumption
high BMI
smoking
stress
what scale can be used to assess hair loss in male androgenic alopecia?
hamilton-norwood scale
what medical management if there for male androgenic alopecia?
Private prescriptions/over the counter
minoxidil 5% - private prescription or OTC
Finasteride 1mg
what is bullous pemphigoid?
autoimmune condition that causes sub-epidermal blistering of the skin due to infiltration of inflammatory cells leading to tense fluid filled blisters
what are 4 kinds of cutaneous cysts?
Pilar
Dermoid
Sebaceous
Epidermoid
what are epidermoid cysts?
in epidermal layer of skin
firm round mobile nodule under skin
typically found on face, neck and trunk
what are sebaceous cysts?
rare sebum containing cysts originating from sebaceous glands
what are pilar cysts?
arise from hair follicles
commonly found on scalp
firm mobile nodule
full of keratin
what are dermoid cysts?
unusual cysts with mature tissues of multiple types due to embryonic origin
commonly on face, neck and ovaries
what is a pyogenic granuloma?
skin growth commonly on head.neck, upper trunk and hands, can also occur in mouth in pregnancy
starts as small red.brown dod which rapidly progresses in days to weaks forming spherical red/brown lesions which may bleed or ulcerate
can be removed
what is a dermatofibroma?
common benign fibrous skin lesions caused by abnormal growth of dermal dendritic histiocyte cells
solitary firm papule/nodules 5-10mm in size, overlying skin dimples on pinching lesion
what are junctional naevi?
flat moles - group or nest of naevus cells at junction of epidermis and dermis
what is classed as an atypical naevus?
> 5mm
ill defined/blurred border
irregular margin and unusual shape
varying shades of colour
flat and bumpy components
