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?
Basal call carcinoma Malignant melanoma – superficial spreading type Malignant melanoma – nodular type Non-healing scab Squamous cell carcinoma
Squamous cell carcinoma
A 32-year old scuba diver who lives in the Maldives had a seizure three days ago. He has no history of epilepsy but he’s had 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?
Acoustic neuroma Glioblastoma multiforme Meningioma Metastases Neurofibromatosis type I
Metastases
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 rolled edges. The GP suspects a basal cell carcinoma.
What investigations are likely to be needed?
Dermatology referral/assessment - 2-week wait
Dermatology referral/assessment – routine
None – it is a non-dangerous chronic condition
None – GP to start treatment
Re-assessment in primary care periodically
Dermatology referral/assessment – routine
What are the risk factors for malignant melanoma
- excessive UV exposure
- skin type 1 (always burns, never tans)
- history multiple moles, atypical moles
- family history melanoma
- previous history melanoma
What is the presentation of a malignant melanoma
ABCDE Asymmetrical shape Boarder irregularity Colour irregularity Diameter >6cm Evolution of lesion (size, shape)
Symptoms: itch, bleeding
Legs in women
trunk in men
What melanomas are found in young/middle aged people with intermittent UV radiation
- surface spreading melanoma
2. Nodular melanoma
What melanoma is found on the face of the elderly patients with chronic UV exposure
Lentigo maligna melanoma
What are the investigations for a suspected malignant melanoma
- refer to dermatology with 2 week wait
- 1st step: dermatoscope
- Gold standard: full thickness excisional biopsy
What is the gold standard investigation for malignant melanoma
full thickness excisional biopsy
Malignant melanoma: What is the first step after a patient has been referred to secondary care
dermatoscope
What do you do if you find an atypical melanocytic lesion
take photographs and r/v at 3 months
Malignant melanoma: What are the investigation if there is metastases
- CXR
- liver ultrasound
- CT chest, abdomen, pelvis
- Brain MRI
What are the differentials for malignant melanoma
- seborrheic wart
- congenital naevi
3.
What are the differentials for malignant melanoma
- seborrheic wart
- congenital naevi
- junctional naevi
- compound naevi
- Intradermal naevi
What is basal cell carcinoma
slow growing invasive tumour of basal cells in the epidermis, rarely metastasises
What is the most common skin cancer
basal cell carcinoma
What are the risk factors for basal cell carcinoma
- excessive UV exposure
- Frequent/sever sunburn in childhood
- Skin type 1
- age
- males
- immunosuppression
- previous history of skin cancer
- family history of skin cancer
What is the most common type of basal cell carcinoma
nodular
Describe basal cell carcinomas (Nodular)
- Small
- skin coloured nodule
- surface telangiectasia (dilated veins - spider veins)
- pearly rolled edges
- +/- ulcerated centre (rodent centre)
What are the investigations for basal cell carcinoma
- Routine referral to dermatology - NOT 2 week week
- Examine with dermatoscope
- The lesion is then usually removed
What is the first line investigation for basal cell carcinoma
routine referral to dermatology - NOT 2 weeks wait
What is squamous cell carcinoma
locally invasive malignant tumour of the epidermal keratinocytes or its appendages, with potential to metastasise
Squamous cell carcinoma is a tumour of …
… keratinocytes (or it’s appendages)
What are the risk factors of squamous cell carcinoma
- excessive UV exposure
- pre-malignant skin conditions e.g. actinic keratoses
- chronic inflammation e.g. leg ulcer, wound scar (Marjolin’s ulcers)
- immunosuppression
- family history
Name a pre-malignant skin condition
actinic keratoses
What is the investigation for squamous cell carcinoma
- refer to dermatology (2 week wait)
- dermatoscope
- (biopsy) & excision
What are features of squamous cell carcinoma
- Keratotic
- Ill-defined nodule
- may ulcerate
- Non-healing lesion
- everted edges
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?
Chicken pox Molluscum contagiosum Atopic eczema Eczema herpeticum Herpes simplex virus
Molluscum contagiosum
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 the touch. Her temperature is 37.9oC and she feels unwell.
i) Most likely diagnosis?
Cellulitis Skin abscess Erysipelas Necrotising fasciitis Gum infection
Erysipelas
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 the touch. Her temperature is 37.9oC and she feels unwell.
ii) Next steps?
Cold compress, reassure, home
Admit to intensive care unit
Take skin swabs, blood cultures, and give paracetamol
Draw around the lesion, give pain relief, oral fluids and antibiotics
Draw around the lesion, give pain relief, oral fluids and antibiotics
What is molluscum contagiosum
viral skin infection (molluscum contagiosum virus, pox virus)
What is the epidemiology of molluscum contagiosum
Preschool children aged 1-4
What are the risk factors for molluscum contagiosum
- transmission: close contact, swimming pools, sexual contact
- HIV infection
- Atopic eczema
What is the presentation of molluscum contagiosum
- Dome shaped
- flesh coloured
- pearly whites
- central umbilication
- May have >100 if immunocompromised/HIV
- systemically well
What are the key words associated with molluscum contagiosum
- pearly white papules
- central umbilication
- systemically well
What are the investigations for molluscum contagiosum
No investigation: clinical diagnosis
What is cellulitis
acute bacterial infection of the dermis and subcutaneous tissue
What is erysipelas
distinct form of superficial cellulitis and sharply demarcated
What are the pathogens that cause cellulitis and erysipelas
- Streptococcus pyogenes
2. Staphyloccus aureus
What are the risk factors for cellulitis or erysipelas
- immunoosupression
- Wounds/ulcers
- IV cannulation
- cut, scratch, insect bite
What is the presentation of cellulitis
acute onset red, painful, hot swollen skin
What is the presentation of erysipelas
acute onset red painful, hot swollen skin
- systemically unwell
- fever
- malaise
- rigors
What is the causative organism that causes periorbital cellulitis
H influenzae
What is peri-orbital cellulitis
Causes painful, swollen skin around the eye
H. influenzae
What is orbital cellulitis
causes visual impairment/limited movement
medical emergency
What are the investigation for cellulitis & erysipelas
Mainly clinical
- FBC: high WBC
- Skin swabs not routinely recommended
What is the management for cellulitis and erysipelas
- draw around lesion
- elevate leg
- encourage oral fluids
- paracetamol/ibuprofen
- oral antibiotics: flucloxacillin
What is the medical management for cellulitis & erysipelas
oral antibiotics: flucloxacillin
When do you admit a patient with cellulitis & erysipelas
acute confusion
tachycardia
tachypnoea
hypotension (sepsis)
What are the complications of cellulitis & erysipelas
- local necrosis
- abscess
- Septicaemia
- necrotising fasciitis
What are the complications of orbital cellulitis
visual impairment
may need orbital decompression surgery
What is necrotising fasciitis
rapidly spreading infection of the deep fascia with secondary tissue necrosis
What is the aetiology of necrotising fasciitis
group A haemolytic streptococcus.
Mixture of aerobic/anaerobic bacteria
What are the risk factors for necrotising fasciitis
- surgical wounds
- skin breakage: IVDU, trauma
- medical co-morbidities e.g. diabetes, malignancy
However, 50% occur in previously healthy people
What are the presenting symptoms and signs of necrotising fasciitis
- severe pain
- erythematous blistering, necrotic skin (late sign)
- systemically unwell: fever and tachycardia
- crepitus (subcutaneous emphysema)
What are the investigations for necrotising fasciitis
- FBC: high WBC
- U+E: high urea due to volume depletion
- high CRP and serum CK
- Blood and tissue cultures
- XR/CT: may show soft tissue gas
What is the management for necrotising fasciitis
extensive surgical debridement
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?
Seborrheic dermatitis Atopic dermatitis Psoriasis (chronic plaque) Psoriasis (guttate) Urticaria
Atopic dermatitis
An otherwise healthy 23-year-old man complains of sore red lesions on his extremities which have a central clearance (targetoid). These appeared after a recurrence of his ‘coldsores’.
What is the diagnosis?
Erythema multiforme Chicken pox Herpes simplex virus Stevens-Johnson’s syndrome Toxic epidermal necrolysis
Erythema multiforme
What is eczema
chronic
What is eczema
chronic itchy inflammatory skin condition (dermatitis)
What is the aetiology/risk factors for eczema
- Atopy: hay-fever, food allergies, asthma
What is the presentation for eczema
- itchy dry skin affecting flexures
- in small infants, can affect the extensor surfaces
- lichenification
What is contact dermatitis
usually due to nickel
(chromate, perfumes, latex, plants)
Type 4 reaction
What type of eczema is due to herpes simplex virus
Eczema herpeticum
medical emergency - admit
What eczema subtype is due to vesicles/blisters on the hands and feet
Dyshidrotic/pompholyx
related to sweating and hot weather
What are the investigations for atopic eczema
not normally needed (clinical diagnosis)
What are the investigations for contact dermatitis
skin patch testing (allergen applied to the skin for 48hrs)
positive result = red raised lesions
What is psoriasis
chronic inflammatory skin changes due to hyper-proliferation of keratinocytes
What is the aetiology of psoriasis
genetic and environment (complex)
tiggers include smoking, alcohol, stress
What is the presentation of psoriasis
- Red/silver plaques on EXTENSOR SURFACES
- can be itchy or painful
- Nail pitting, onycholysis (when the nail separates from the nail bed)
- symmetrical polyarthritis
What do you find on examination of a patient with psoriasis
- Koebner phenomenon = lesions appear in traumatised skin
2. Auspitz sign = removal of scales causing bleeding
What is the acronym that denotes symptoms of psoriasis
POSH
Pitting
Onycholysis
Subungual
hyperkeratosis
What is erythema multiforme
acute self-limiting inflammation of skin and mucus membranes
What is the epidemiology of erythema multiforme
Any age group in children and young adult
M:F 2:1
What is the aetiology and risk factors for erythema multiforme
- Infection = virus (Herpes Simplex Virus) bacterial (mycoplasma, chlamydia) fungal (histoplasmosis)
- pregnancy
- Drugs = sulphonomides (antimicrobial but not antibiotic) and penicillin
- Inflammation = rheumatoid arthritis, SLE, sarcoid
- Malignancy = leukaemia, lymphoma, myeloma
What is the presentation of erythema multiforme
- prodromal symptoms
- TARGET LESIONS
- itching, burning, painful
- May fade which will lead to pigmentation
What is Steven-Johnson syndrome
Affects two mucosal sites (conjunctiva, lips, mouth, oesophagus)
patient is systemically unwell
Shock (hypotension, tachycardia)
What are the investigations for erythema multiforme and Steven-Johnson syndrome
usually clinical diagnosis
- FBC = increased WBC
- raised ESR and CRP
- HSV serology
- throat swab
- CXR
