11. Dermatology Flashcards
A 64 year old man presents with a lesion on his upper ear that has been present for months but has now begun to ulcerate. On examination: non-pigmented, hyperkeratotic, crusty lesion with raised everted edges on the pinna.
What is the most likely diagnosis? A. Basal call carcinoma B. Malignant melanoma – superficial spreading type C. Malignant melanoma – nodular type D. Non-healing scab E. Squamous cell carcinoma
E. Squamous cell carcinoma
Hints: Age Classic site Non-pigmented Hyperkeratotic, crusty Everted edges
A 64 year old man presents with a lesion on his upper ear that has been present for months but has now begun to ulcerate. On examination: non-pigmented, hyperkeratotic, crusty lesion with raised everted edges on the pinna.
How should the GP proceed? A. Provide sun exposure advice B. Monitor for changes with serial follow up C. Treat in primary care D. Dermatology referral - routine E. Dermatology referral – 2 week wait
E. Dermatology referral – 2 week wait
Hints:
Diagnosis = SCC
Potentially malignant spread
Must refer urgently as for melanoma
A 32-year old professional surfer had a seizure three days ago. He has no history of epilepsy and reports headaches for the past 5 months. The headaches are worse when he goes to bed. On examination, a dark irregular skin lesion is found on the back of his neck. An MRI scan shows multiple lesions across both cerebral hemispheres.
What is the most likely diagnosis? A. Acoustic neuroma B. Glioblastoma multiforme C. Meningioma D. Metastases E. Neurofibromatosis type I
D. Metastases
Hints:
- Signs of raised ICP (brain mets)
- Lesion suspicious of melanoma
- Significant sun exposure
A 76-year-old woman has recently attended her GP because of a ‘spot that won’t go away’. The lesion is on her nose and has pearly, rolled edges with telangiectasias.
What is the most likely diagnosis? A. Squamous cell carcinoma B. Molluscum contagiosum C. Basal cell carcinoma D. Acne rosacea E. Acne vulgaris
C. Basal cell carcinoma
Hints:
Classic site
Features of BCC
Malignant melanoma Definition and Epidemiology
Definition: invasive, malignant tumour of the epidermal melanocytes which has the potential to metastasize
Epidemiology:
Least common skin cancer
Average age is 63 years (but can affect much younger people ~30 years)
Malignant melanoma RF
Modifiable - Excessive UV exposure
Non-modifiable
- Skin type I* (always burns, never tans)
- History multiple moles, atypical moles
- Family Hx/PMHx melanoma
*Fitzpatrick skin types: 1-6 (1 is fairest skin, 6 has darkest skin)
Malignant Melanoma Presentation - Signs and Symptoms
Where is it most commonly found?
What is the 7 point check list and when do you refer to 2-week-wait
Asymmetry (2) Borders irregular Colour irregular (2) Diameter >7mm (1) Expanding size (evolution of lesion) (2)
Symptoms:
- Inflammation (1)
- Oozing (1)
- Change in sensation (1)
Legs in women, trunk in men
If >3 = 2 week referral
Types of Melanoma (4)
LANS
- Lentigo Maligna (Elderly, face, Chronic UV)
- Acral Lentiginous (Darker skin types, palm/soles/nails)
- Nodular* (raised, black, poor prog as vertical spread at Dx)
- Superficial Spreading (Most common)
*May not fit 7 pt criteria – NICE say refer if you suspect
Differential: melanocytic lesions
Slightly Commoner In Just Countries
Seborrheic wart
- (Elderly)
- Often multiple, Wart-like, greasy, Stuck on appearance
Congenital naevi
- Can be large, pigmented, hairy
Intradermal naevi
- Dome-shaped papule/nodule
Junctional naevi
- Small, flat, dark
Compound naevi
- Raised, warty, hairy
Cancer: malignant melanoma Investigation(s)
GP: 2 week dermatology referral
Dermatology:
- Examination with dermatoscope
Definitive: full thickness excisional biopsy
Atypical melanocytic lesion - take photographs and r/v at 3 months
If there is a suggestion of metastases:
- CXR (lung mets)
- Liver ultrasound (liver mets)
- CT chest, abdomen, pelvis
- Brain MRI
Basal cell carcinoma Definition and Epidemiology
Slow growing locally invasive tumour of basal cells of the epidermis, rarely metastasizes
Epidemiology: older individuals, most common (skin) cancer
Basal cell carcinoma
Modifiable
- Excessive UV exposure
- Frequent/severe sunburn in childhood
Non-modifiable
- Skin type I
- Older age
- Males
- Immunosuppression
- PMHx/FHx skin cancer
Presentation & subtypes:
Most common over head and neck (nose)
Nodular (most common) - Small - Skin coloured nodule - Surface telangiectasia - Pearly rolled edge ± Ulcerated centre (rodent ulcer)
Superficial (Flat)
Sclerosing/morphea (Scar like)
Pigmented (May appear like melanoma)
Investigation BCC
Routine referral to dermatology – NOT 2 week wait, or if low risk Mx/follow up in primary
Examine with a dermatoscope
The lesion is then usually removed
Squamous cell carcinoma Definition and Epidemiology
Definition: locally invasive malignant tumour of the epidermal keratinocytes or its appendages, with potential to metastasize
Epidemiology: middle aged and elderly
SqCC Risk factors
- Excessive UV exposure
- Pre-malignant skin conditions e.g. actinic keratoses (crumbly yellow-white crusting, premalignant)
- Chronic inflammation e.g. leg ulcer, wound scar (Marjolin’s ulcer - chronic defect causes proliferation of epithelium which becomes unchecked)
- Immunosuppression
- Family history
SqCC Presentation
Keratotic (scaly, crusty) Ill-defined nodule May ulcerate Non-healing lesion Everted edges
SqCC Investigation
Refer to dermatology (2 week wait)
Dermatoscope
(Biopsy) & excision
A 4-year old girl presents to the GP with multiple lesions on her face. The lesions are raised and shiny, non-tender, non-erythematous, and 3 mm in diameter. They have an umbilicated centre. The patient is known to be HIV positive.
What is the most likely diagnosis? A. Chicken pox B. Molluscum contagiosum C. Atopic eczema D. Eczema herpeticum E. Herpes simplex virus
B. Molluscum contagiosum
Hints
Classic appearance
HIV
A 52-year-old woman presents to the GP with redness and swelling of her right cheek. On examination the area of erythema is well-demarcated and warm to touch. Her temperature is 37.9C and she feels unwell.
What is the most appropriate management plan for this patient?
A. Cold compress, reassure, home
B. Admit to intensive care unit
C. Take skin swabs, blood cultures, and give paracetamol
D. Draw around the lesion, give pain relief, oral fluids and antibiotics
E. Emergency dentist referral
D. Draw around the lesion, give pain relief, oral fluids and antibiotics
Hints
Well-demarcated & systemic upset – probably erysipelas
Molluscum contagiosum definition and epidemiology and RF
Definition: viral skin infection (molluscum contagiosum virus, pox virus)
Epidemiology: preschool children aged 1-4
RF:
- Transmission: close contact, swimming pools, sexual contact
- HIV infection
- Atopic eczema
Presentation of Molluscum contagiosum and Invx
- Dome shaped, flesh coloured, pearly white papules
- Central umbilication
- May be >100 if immunocompromised/HIV
- Systemically well
No investigations needed: clinical diagnosis
Cellulitis & erysipelas Definition and Aetiology
Cellulitis: acute bacterial infection of the dermis and subcutaneous tissue
Erysipelas: distinct form of superficial cellulitis which is sharply demarcated
Aetiology: Results from penetrating injury allowing pathogenic bacteria to enter the skin
- Streptococcus pyogenes
- Staphyloccus aureus
- (H. influenzae – periorbital)
Cellulitis & erysipelas RF
- Immunosuppression
- Wounds, ulcers
- IV cannulation
- Skin injury: cut, scratch, insect bite
Cellulitis & erysipelas Presentation
Appearance:
- acute onset red, painful, hot, swollen skin
- well-defined raised border (erysipelas)
Systemic signs:
- systemically unwell with fever, malaise, rigors (erysipelas)
Periorbital cellulitis:
- Causes painful, swollen skin around eye
Orbital cellulitis:
- Causes visual impairment/limited movement
Medical emergency
Cellulitis & erysipelas Invx and Mx, when do you admit?
Investigations:
(Mainly clinical)
FBC: high WCC
Skin swabs not routinely recommended
Mild cases:
- Draw around lesion
- Elevate leg
- Encourage oral fluids
- Paracetamol/ibuprofen
- Oral antibiotics: local policy (often flucloxacillin)
Follow up: manage underlying risk factors/comorbidities (e.g. DM)
Admit if septic
- Acute confusion, tachycardia, tachypnoea, hypotension
Cellulitis & erysipelas Complications and prognosis
Complications:
- Local necrosis
- Abscess
- Septicaemia
- Necrotising fasciitis
Orbital cellulitis:
- May need orbital decompression surgery (to drain sinuses)
Prognosis: good with treatment
Necrotising fasciitis definition and aetiology
Definition: rapidly spreading infection of the deep fascia with secondary tissue necrosis
Aetiology: group A beta-haemolytic streptococcus, mixture aerobic/anaerobic bacteria
Necrotising fasciitis Risk factors
Surgical wounds
Skin breakage: IV drug use, trauma
Medical comorbidities e.g. diabetes, malignancy
50% occur in previously healthy people
Necrotising fasciitis Presentation & signs:
Severe pain
Erythematous blistering, necrotic skin (late sign)
Systemically unwell: fever and tachycardia
Crepitus (subcutaneous emphysema - production of gas within soft tissues)
Necrotising fasciitis Invx
What is the mortality rate?
Bloods:
- FBC: high white cells
- U+E: high urea due to volume depletion
- High CRP, serum CK
- Blood and tissue cultures
XR/CT: may show soft tissue gas
Urgent referral: extensive surgical debridement
NB: Ix shouldn’t delay referral
20-40% mortality
A 12-year-old girl presents with dry, itchy skin that involves the flexures in front of her elbows and behind her knees. She has symptoms of hay fever and was diagnosed with egg and milk allergy at 6 months old.Her mother has asthma.
What is the most likely diagnosis? A. Seborrheic dermatitis B. Atopic dermatitis C. Psoriasis (chronic plaque) D. Psoriasis (guttate) E. Urticaria
B. Atopic dermatitis
Hints: Age Flexures Allergies FHx atopy
A 23-year-old man was recently given penicillin for a throat infection (now resolved). He now complains of sore red ‘targetoid’ lesions on his extremities. Later he develops ulcers around his lips and conjunctiva.
What is the diagnosis? A. Erythema multiforme B. Chicken pox C. Herpes simplex virus D. Stevens-Johnson’s syndrome E. Toxic epidermal necrolysis
D. Stevens-Johnson’s syndrome
Hints:
Target lesions
TWO mucosal sites affected!
Subtypes of Eczema
Atopic dermatitis Seborrheic dermatitis Contact dermatitis Dyshidrotic/pompholyx Discoid/nummular eczema Eczema herpeticum (Ex!)
Atopic dermatitis
Type I reaction (IgE-mediated)
- ‘lichenification’/lichen simplex
- Flexures
- Atopy
Seborrheic dermatitis
- Yellow, greasy scales
- Can cause nappy rash
- Adults: dandruff, plaques on nasolabial folds, eyebrows
- Associated with malassezia yeasts
Contact dermatitis
Type IV reaction (T cell mediated)
Nickel (chromate, perfumes, latex, plants) hypersensitivity
Dyshidrotic/pompholyx
- Acute recurrent eruptions of vesicles/blisters on palms/soles
- Related to sweating (hot weather)
Discoid/nummular eczema
- Scattered, round patches
Itchy (Lesions normally lasts a few months) - Hx: atopic eczema, skin injury
Men aged 55-65
Women in adolescence
Can occur after insect bite, burn, abrasion.
Eczema herpeticum
Herpes simplex infection in eczema sufferer - MEDICAL EMERGENCY, ADMIT
If disseminated can affect multiple organs including the eyes, brain, lung, and liver. It can rarely be fatal. Needs antivirals (oral or IV).
Seek ophthalmological advice if lesions are near the eye as can cause damage to vision.
Eczema Investigations
Atopic eczema: not normally needed (clinical diagnosis)
Contact dermatitis: skin patch testing (allergen applied to skin for 48h);
positive result = red raised lesion
Psoriasis Definition, Epidemiology and Aetiology/RF
Definition: chronic inflammatory skin disease due to hyperproliferation of keratinocytes
Epidemiology: 2% of the population, peak age 20 years
Aetiology and risk factors: genetic and environmental (complex); triggers include smoking, alcohol, stress
Psoriasis Presentation:
Red/silver, scaly plaques, EXTENSOR SURFACES
Can be itchy or painful
Nail pitting, onycholysis
Symmetrical polyarthritis (looks like rheumatoid arthritis)
Psoriasis Definition, and Aetiology
Definition: chronic inflammatory skin disease due to hyperproliferation of keratinocytes
Excess proliferation of epidermal cells and accelerated upward migration of immature keratinocytes. Sloughing of skin cells is not quick enough to match increased migration to surface –> plaque formation
Psoriasis Epidemiology and RF
Epidemiology: 2% of the population, peak age 20 years
Risk factors: genetic and environmental (complex); triggers include smoking, alcohol, stress
Psoriasis Presentation:
Red/silver, scaly plaques, EXTENSOR SURFACES
Can be itchy or painful
Nail pitting, onycholysis
Symmetrical polyarthritis (looks like rheumatoid arthritis)
Psoriasis Examination
Koebner phenomenon: lesions appear in traumatised skin
Auspitz sign: removal of scale –> bleeding
Psoriasis Subtypes (7)
Nail Chronic Plaque Palmar Plantar Psoriatic Arthritis Pustular (Generalised vs Palmar Plantar) Guttate Erythroderma
Describe the following forms of Psoriasis: Nail Chronic Plaque Palmar Plantar Psoriatic Arthritis
Nail (POSH)
- Pitting
- Onycholysis
- Subungual Hyperkeratosis (build up of keratin under nail bed)
- Chronic Plaque (Silver scales)
- Palmar Plantar (dry, red thick skin, fissures)
- Psoriatic Arthritis (Telescoping)
Describe the following forms of Psoriasis:
Pustular (Generalised vs Palmar Plantar)
Pustular psoriasis
(10% have plaque psoriasis)
Generalised - Sudden withdrawal steroids/infection; Needs hospitalisation
Palmar plantar
Associations: smoking, middle-aged women, autoimmune thyroid disease
Describe the following forms of Psoriasis:
Guttate
Erythroderma
Guttate - After strep throat
‘Salmon pink’
Drop-like lesions
Erythroderma
Generalised red, inflamed skin
1/3 cases due to worsening psoriasis
Needs Hospitalisation
Erythema multiforme definition and epidemiology
Definition: acute self-limiting inflammation of skin and mucous membranes
Epidemiology:
Any age group, common in children and young adults
M:F = 2:1
Erythema multiforme Aetiology and risk factors:
Infection: viral (herpes simplex virus), bacterial (mycoplasma, chlamydia), fungal (histoplasmosis),
Inflammation: rheumatoid arthritis, SLE, sarcoid
Malignancy: leukaemia, lymphoma, myeloma
Pregnancy
Drugs: sulphonomides, penicillin
(Precipitating factor only identified in 50%)
Presentation of Erythema multiforme
Prodromal symptoms
Target lesions: : rim of erythema surrounding a paler area; itching, burning, painful
May fade –> pigmentation
What is the severe form of Erythema multiforme called and what does it affect?
Steven Johnson Syndrome: affects 2 mucosal sites: eyes, lips, mouth, pharynx, oesophagus, GI tract, kidneys, liver, anus, genital area, or urethra
Presentation of SJS
Systemically unwell: sore throat, fever, cough, headache, diarrhoea and vomiting
Shock: hypotension, tachycardia
Investigations: EM and SJS
Usually clinical diagnoses FBC: white cells ++ ESR, CRP ++ HSV serology, etc. Throat swab CXR (sarcoid, atypical pneumonia)
