Dermatology Flashcards
History
- Social
- Occupation, hobbies, sun beds, skin type
Rash/lesions - definitions
- Macule
- Patch
- Papule
- Plaque
- Nodule
- Vesicle
- Bulla
- Pustule
- Lichen simplex
- Nummular lesion
- Annular lesion
- Reticulate
- Change in skin colour without elevation
- Large area of colour change, smooth surface
- Circumscribed raised lesion (0.5-1cm)
- Circumscribed, palpable lesion (>1cm), most elevated
- Circumscribed raised lesion (>1cm)
- Raised lesion that contains fluid
- Larger vesicle (>0.5cm)
- Containing purulent material
- Hard skin thickening, with accentuated skin markings
- ‘Coin-like’
- In a ring
- ‘Net-like’
Loss of skin layers
- Skin layers (3)
- Erosion - definition
- Ulceration
- Epidermis, dermis, subcutaneous layer
- Superficial epidermis loss, heals without scarring
- Loss of whole epidermis + upper dermis, causes scars
Skin exam
- Hidden areas
- Other things to offer
- Nails, web spaces, scalp, mouth, flexures
2. Lymph nodes, pulses, joint examination
Topical steroids
- Mild
- Moderate
- Potent
- How long to wait before applying after flare up
- Apply how often
- 1% hydrocortisone
- Eumovate, 2.5% hydrocortisone
- Betnovate
- 48 hours
- Once a day
Eczema - management
- Pruritis
- Management - 1st line
- 2nd line
- 3rd line
- Antihistamine
- Topical emollients + steroid (30 minutes in between)
- Topical tacrolimus, bandages, stockinette garments
- Phototherapy, systemic medication
Eczema - secondary infection
- Common bacterial organisms (2)
- Management - combined antibiotic + steroid cream
- Secondary viral infection from chicken pox in children
- Dermatological emergency from HSV-1
- Presentation
- Management
- Staph. aureus, strep. pyogenes
- Fucidin H
- Molluscum contagiosum
- Eczema herpeticum
- Painful worsening eczema, clustered blisters (like early cold sores), punched out erosions, fever, lethargy, reduced oral intake
- Aciclovir
Psoriasis - general
- Commonest type
- What percentage have associated arthralgia
- Flexural
- Erythrodermic
- Management
- Generalised pustular
- Chronic plaque
- 5%
- In genitalia/axilla (friction); erythematous, shiny, no scale
- Total body redness/heat/pain, no clear plaques, can feel systemically unwell + become hypotensive
- Admit to hospital
- Psoriasis flare, leading to pustules with plaques
Chronic plaque psoriasis
- Presentation
- Plaques found where
- Asuptiz sign
- Which medication can exacerbate plaque psoriasis
- Raised erythematous patches, scale (silver-white build up of dead skin cells), often itchy / painful
- Behind ears, genitals, scalp, nails, umbilicus, extensor surfaces of knees/elbows, natal cleft
- Capillary bleeding from plaque scratching
- Beta blockers, lithium, NSAIDs, ACE-i, antimalarials
Guttate psoriasis
- Presentation
- Often follows what
- Common subsequent development of what
- Management
- ‘Raindrop lesions’ - small, pink plaques on trunk
- Strep sore throat
- 1/3 develop chronic plaque psoriasis
- Resolves spontaneously so reassurance, topical psoriasis management if lesions symptomatic
Psoriasis - management
- 1st line (mild, localised)
- If extensive disease (2)
- Regular emollient to improve scale
Topical potent steroid OD (not for longer than 8 weeks)
Vit D analogue OD (reduce scale, not inflammation)
Apply one in morning + one at night - Phototherapy
PO therapies - methotrexate, retinoids, biologics (useful if joint disease)
Acne - general
- Causes - hormone conditions (5)
- Causes - medication
- PCOS, virilising tumours, congenital adrenal hyperplasia, Cushing’s, acromegaly
- Topical / systemic steroids, OCP, isoniazid, phenytoin, barbiturates, ciclosporin, lithium
Acne - management
- 1st line
- 2nd line
- 3rd line
- ABX of choice
- When to avoid above type, what to use instead
- Complication of long-term ABX
- Management
- Alternative to PO ABX, risk + management of this
- 4th line (dermatologist only)
- Side effects
- Other principles of management
- Single topical therapy (benzoyl peroxide, retinoids)
- Topical combination (ABX, benzoyl peroxide, retinoid)
- Add PO ABX (remove topical ABX) to BP / retinoid
- Tetracyclines (e.g. lyme, oxytetra, doxy)
- Pregnant (erythromycin instead) / breastfeeding, children under 12 years old
- Gram-negative folliculitis
- High dose PO trimethoprim
- Dianette (co-cyrindiol) - high VTE risk so 3 months max - slows sebum production
- PO retinoid - isotretinoin
- Dry skin/mucous membranes, nosebleeds, joint pain, photosensitivity, tetarogenic (stop for a month before becoming pregnant), suicidal ideation
- Minimise: humidity, oils, cosmetics, abrasive skin treatments, washing face (maximum 2x a day)
Stop smoking
Eat plenty of fruit and vegetables
Women: consider COCP if need contraception
Actinic (solar) keratoses
- What it is
- Found where
- Description
- Sign of AK having malignant change
- Changes to
- Management - single lesion
- Pre-malignant skin condition
- Exposed skin (worked outdoors/high UV exposure)
- Small (<1cm), crusty/roughscaly, pink/red/brown, raised, keratotic, irregular edges - PAINLESS
- Rapid growth, painful, inflamed
- Squamous cell carcinoma
- Cryotherapy, topical fluorouracil/imiquimod/diclofenac
Squamous cell carcinoma
- Presentation
- Common sites
- Risk factors
- Poor prognosis
- Main management
- Undular nodular lesions, keratotic, ill-defined, may ulcerate, can be painful
- Face, scalp, back of hands
- UV exposure, actinic keratosis, Bowen’s disease, chronic inflammation, immunosuppression
- > 2cm wise, lip/ear lesion, immunosuppression history
- Surgical excision (4-6mm margin)
Radiotherapy - large non-resectable lesions
Basal cell carcinoma (rodent ulcer)
- Presentation - initial
- Later
- Common sites
- Risk factors
- Referral speed
- Management options
- Nodule/papule: pearly, translucent, telangiectasia
- May ulcerate leaving central ‘crater’
- Sun-exposed - head and neck
- Age, fair skin, UV exposure, radiation, immunosuppression, previous BCCs
- Routine (consider 2ww if delay may have significant impact e.g. due to lesion site / size)
- Excision, radiotherapy, grafting, curettage, cautery, cryotherapy
Malignant pigmented lesions
- Assessment - ABCDE
- What regulates melanocytes
- Junctional naevus =
- Intradermal naevus =
- Intermediate naevus =
- Compound naevus =
- Asymmetry
Border (? irregular)
Colour - variety may suggest dysplasia / malignancy
Diameter (>1cm more likely to be malignant)
Evolving - MSH
- Melanocyte proliferation at dermo-epidermal junction
Brown, flat lesions - Melanocytes in dermis
Skin-coloured, raised lesions - Central melanocytes in dermis, peripheral in junction
Raised centre, brown border - Melanocytes at junction + within dermis
Raised, brown lesion
Malignant melanoma
- Risk factors
- Scoring system (prognosis depends on)
- What indicates poorer prognosis (3)
- Management
- UV exposure, light/poorly tanning skin/hair, personal/FH, presence of giant congenital melanocyte naeve, multiple common moles, mole change
- Breslow thickness
- Ulceration, lymph node involvement, skin metastases
- Excision with a 2mm margin
FNA if lymph nodes palpable
Cellulitis
- Management - uncomplicated (staph. aureus)
- Mild MRSA
- Extensive MRSA
- High-risk groups (3)
- Flucloxacillin
- Doxcycline
- Vancomycin
- Venous stasis, lymphoedema, diabetes
Necrotising fasciitis
- High-risk groups (3)
- Presentation
- Diagnosis
- Management
- IVDUs, post-surgery, post-trauma
- Pain out of proportion to lesion, systemically unwell, rapid progression
- USS but also clinical diagnosis
- Surgical debridement of all necrotic tissue
Broad spectrum ABX
Gas gangrene
- Causative organism
- Features
- Complication
- Management
- C perfringens
- Tender, skin oedema, haemorrhaging blebs/bullae, crepitus on palpation
- Toxaemia and shock
- Debridement and excision, ABX, maybe amputation
Erythroderma
- What it is
- Causes
- Presentation
- Management
- Exfoliative dermatis involving >90% of skin surface
- Previous skin disease e.g. eczema and psoriasis, lymphoma, drugs, idiopathic
- Skin inflamed, oedematous + scaly
Systemically unwell, malaise, lymphadenopathy - Treat underlying cause, + emollients, wet wraps, topical steroids
Lesion - 2ww referral
- Scale to use
- Major features (2 points) (3)
- Minor features (1 point) (4)
- Other situations where 2ww is considered
- 7-point scale
- Change in size, irregular shape, irregular colour
- Largest >7mm, inflammation, ooze, sensation change
- Dermatoscopy suggests MM, or SCC suspicion
Dermatitis herpetiformis
- What it is
- Linked to
- Chronic, itchy, blister clusters
2. Coeliac disease - underlying gluten enteropathy
Kaposi’s sarcoma
- Tumour of what
- Presentation
- Associations
- Linked virus (apart from HIV)
- Vascular and lymphatic endothelium.
- Slow growing purple cutaneous nodules, elderly men
- Immunosuppression (this form much more aggressive, affects those with HIV-related disease)
- HHV-8 (human herpes virus 8)
Stevens-Johnson Syndrome / Toxic Epidermal Necrolysis
- Difference between them
- Causes - medication (5)
- Causes - infections (4)
- Associated with what
- Symptoms
- Management
- SJS <10% BSA, TEN >10%
- AEDs, ABX, allopurinol, NSAIDs, isotretinoin
- HSV, mycoplasma, CMV, HIV
- HLA genetic types
- Systemically unwell, positive Nikolsky sign
- Stop precipitant, supportive, IVIG, other immunosuppressants
Viral widespread rashes (exanthemas) - part 1
- Measles - rash
- Other signs/symptoms
- Complications (5)
- Scarlet fever - associated virus
- Rash
- Management
- Complications - associated with virus
- Rubella - rash
- Other symptoms
- Risk in pregnancy (triad)
- Other complications (2)
- Erythematous, macular rash behind ears/on face 3-5 days post-fever, then spreads
- Koplik spots, fever, corzyal symptoms, conjunctivitis
- Otitis media, diarrhoea, pneumonia, encephalitis, blindness
- Group A strep (tonsils/skin)
- Red-pink, blotchy, macular, rough skin. Starts on trunk, spreads outwards (red cheeks)
- ABX for underlying infection
- Post-strep GN/reactive arthritis, rheumatic fever
- Milder erythematous, macular, starts on face (3 days)
- Mild fever, joint pain, sore throat, lymphadenopathy (behind ears/back of neck)
- Congenital rubella syndrome - deaf, blind, congenital heart disease
- Thrombocytopenia, encephalitis
Viral widespread rashes (exanthemas) - part 2
- Parvovirus B19 - aka (2)
- Rash
- Other signs/symptoms
- Complications
- Roseola - cause
- Presentation
- Rash
- Complication
- Slapped cheek syndrome / Erythema infectiosum
- Rapid diffuse bright red rash on both cheeks; then days later a reticular, raised, itchy, erythematous rash on trunk/limbs
- Starts with mild fever, coryzal symptoms
- Aplastic anaemia (if immunocompromised), encephalitis/meningitis, hepatitis, myocarditis, nephritis
- Human Herpesvirus 6 (HHV-6) + 7 (HHV-7)
- Fever >40, sudden, last 3 days then disappears
- Mild itchy erythematous macular, across arms, legs, trunk and face
- Febrile convulsion
Erythema multiforme
- Type of reaction
- Causes
- Rash
- Other symptoms
- Erythema nodosum - description
- Causes - hypersensitivity reactions
- Causes - chronic diseases (2)
- Type 4 hypersensitivity reaction
- Viruses e.g. HSV, medications, mycoplasma pneumonia
- Widespread, itchy, target lesions
- Mild pyrexia, stomatitis, muscle/joint/head aches
- Red, inflamed, tender SC nodules across both shins
- Recent strep. infection, TB, pregnancy, NSAIDs
- IBD, sarcoid
Pityriasis Rosea
- Starts with
- Rash
- Other symptoms
- Resolution
- Pityriasis/tinea versicolour - cause
- Rash
- Management
- ‘Herald patch’ on torso - faint red/pink (lighter in darker skinned patients), scaly, oval lesion >2cm wide, 2+ days before rest of rash
- Same lesions but smaller, ‘christmas tree’ pattern over ribs
- Generalised itch, low fever, headache, lethargy
- Spontaneous after about 6 weeks
- Superficial cutaneous fungal (Malassezia furfur)
- Truncal hypopigmented/pink/brown patches, more noticeable after suntan
- Ketoconazole shampoo, 2nd line PO itraconazole
Chicken Pox
- Rash
- Other symptoms
- Complications
- Management
- Widespread, erythematous, raised, vesicular (fluid filled), blistering lesions, start on trunk/face
- Pyrexia, itch, general malaise
- Conjunctival lesions, encephalitis (ataxia)
- Aciclovir if immumocompromised, <4 weeks old, at risk or complications
Hand, foot and mouth
- Cause
- Starts with
- Rash
- Resolution
- Coxsackie A viruses
- Incubation 3-5 days, then typical viral illness symptoms
- Small mouth ulcers first, then discreet red spots on hands, feet, around mouth - may blister/itch
- Spontaneous after 10 days
Molluscum contagiosum
- Virus type
- Rash
- Resolution (+ other options)
- Pox
- Small, flesh coloured papules with central dimple in ‘crops’
- Spontaneous after 18 months, can maybe use salicylic acid/cryotherapy
Non-blanching rashes
- Differentials
- FBC - suggestive findings
- U+E deranged - suggests
- Hypertension
- Urine dipstick (proteinuria, haematuria)
- Meningococcal septicaemia
HSP (legs/buttocks, associated abdo/joint pain)
ITP (develops over several days, otherwise well)
Leukaemia (gradual petechiae, anaemia, lymph nodes)
HUS (oliguria, anaemia, recent diarrhoea)
Mechanical (petechiae in SVC distribution)
Other (trauma, viruses)
2. Anaemia - HUS, leukaemia Thrombocytopaenia - ITP, HUS 3. HUS/HSP with renal involvement 4. HSP, HUS 5. HUS, HSP with renal involvement
Impetigo
- Cause
- Non-bullous - symptoms
- Bullous - description
- Management
- If bullous widespread, called what
- Sign of this
- Management
- Staph. aureus, strep. pyogenes
- Sores around nose/mouth that leak fluid to form golden crust, no systemic upset
- Larger fluid-filled vesicles (commoner in <2 years old)
- Local/non-bullous = fusidic acid, PO flucoxacillin if widespread/bullous
- Staphylococcus Scalded Skin Syndrome.
- Positive Nikolsky sign, + systemic (fever, irritability, lethargy, dehydration)
- Admit, IV fluids, IV ABX
Scabies
- Symptoms
- Management - 1st line
- 2nd line
- If immunocompromised e.g. HIV, what happens
- Symptoms/signs
- Management
- Widespread itch, track marks in finger web spaces
- Permethrin 5%
- Malathion 0.5%
- Crusted (Norwegian) scabies
- Generalised red patches, turn into scaly plaques, may not be itchy
- Ivermectin, isolation
Ringworm (tinea)
- Name depending on affected location: scalp, feet, groin, body
- Incognito =
- Presentation
- Capitis - consequence if untreated
- Commonest cause
- Cause acquired from cats/dogs + diagnosis
- Most useful investigation
- Management
- Head lice - infected with what
- Management
- Capitis, pedis, cruris, corporis
- Fungal skin infection incorrectly treated with topical steroids, causing diffuse worsening of rash
- Circular, itchy, erythematous, scaly, well-demarcated
- Kerion (raised, pustular, spongy/boggy mass)
- Trichophyton tonsurans
- Microsporum canis (green under Wood’s lamp)
- Scraping of area
- Ketoconazole shampoo for 2 weeks
Oral antifungals: terbinafine if TT, griseofulvin if MC - Pediculus humanus capitis parasite
- Dimeticone 4% lotion
Seborrheic dermatitis
- Associated organism
- Associated conditions
- Presentation
- Scalp management
- Face/body management
- Malassezia furfur
- HIV, Parkinson’s
- Eczematous lesions on sebum-rich areas: scalp, periorbital, auricular and nasolabial folds
Non-rash: otitis externa, blepharitis - 1st line OTC zinc pyrithione/tar, 2nd ketoconazole
- Topical ketoconazole, short course topical steroids
Pyoderma gangrenosum
- Location
- Presentation - rash
- Other symptoms
- Commonest cause
- Associated conditions
- Management - 1st line
- Lower limb
- Small red papule, becomes deep red necrotic ulcers with violaceous border
- Systemic symptoms e.g. fever, myalgia
- Idiopathic (>50%)
- IBD, RA, SLE, haem malignancy, PBC
- Oral steroids
Lichen planus
- Rash location
- Description
- Non-rash signs
- Drug causes (3)
- Management
- Lichen sclerosus =
- Palms, soles, genitalia, arm flexor, buccal mucosa
- Itchy, papular, polygonal shape, white lines on surface (Wickham’s striae), with Koebner phenomenon
- Nail plate thinning, longitudinal ridging
- Gold, quinine, thiazides
- Topical steroids (PO if extensive), benzydamine mouthwash or spray
- Itchy white genital plaques in elderly females (give topical steroids)
Pruritis - systemic causes (other symptoms)
- Liver disease
- Iron deficiency anaemia
- Polycythaemia
- Chronic kidney disease
- Lymphoma
- Other causes
- Alcohol, chronic stigmata (spider naevi, bruising, palmar erythema, gynaecomastia), decompensation signs (ascites, jaundice, encephalopathy)
- Pale, microcytic anaemia, koilonychia, atrophic glossitis, post-cricoid webs, angular stomatitis
- Worst after warm bath, ‘ruddy’ complexion, gout, peptic ulcer
- Lethargy, pallor, oedema, weight gain
- B symptoms, lymphadenopathy, fatigue, hepatosplenomegaly
- Thyroid disease, DM, pregnancy, ‘senile’ pruritus, urticaria, eczema / scabies / psoriasis / pityriasis rosea