Dermatology Secondary Care Flashcards
What is bullous pemphigoid?
A chronic, autoimmune, subepidermal blistering skin disorder.
How does bullous pemphigoid differ from pemphigus?
Pemphigus - intra-epidermal blistering, painful not pruritic
Pemphigoid - sub epidermal blistering, painful and pruritic
What is the median age of onset in bullous pemphigoid?
80 years
What is the autoantigen in bullous pemphigoid and what is its function?
Type XVII collagen (COL17)
in the basement membrane
What are three risk factors for bullous pemphigoid?
Lichen planus/psoriasis
NSAIDS/furosemide/captoptil
Radiotherapy
How does bullous pemphigoid present?
Urticarial/erythematous rash on limbs precedes blisters - urticarial prodrome
Blisters/bullae occur in skin flexures, are fluid filled
Post inflammatory hyperpigmentation/milia
Patient is otherwise well
How is bullous pemphigoid diagnosed?
Skin biopsy followed by direct immunofluorescence (DIF)
Deposit of IgG and C3 on the epidermis side of the dermal/epidermal junction
What is seen on the histology of a bullous pemphigoid patient?
Subepidermal blister with fibrin and inflammatory infiltrate and eosinophilic predominance. Intact epidermis
What is the management of bullous pemphigoid?
Urgent referral to secondary care/admission
Dermovate cream
If more severe, PO prednisolone
If systemic steroid treatment lasts more than one month, what is given?
PPI and bisphosphonates
What is a complication of bullous pemphigoid?
Secondary infection and sepsis
What is pemphigus?
A group of autoimmune disorders where there is blistering of the skin and/or mucosal surfaces.
What is the pathophysiology of pemphigus?
Circulating IgG autoantibodies bind to antigens (desmosomes) on the surface of keratinocytes leading to acantholysis (keratinocytes separate from each other)
What are some risk factors for pemphigus?
Female
Older age
Asian and Ashkenazi Jews
Pregnancy and stress
What are the main three subtypes of pemphigus?
Pemphigus vulgaris
Pemphigus foliaceus
Paraneoplastic pemphigus
How does the skin symptoms of pemphigus present?
Blisters on normal or erythematous skin and are flaccid
Affected skin is painful but rarely pruritic
Intertriginous areas - granulation and crusting
What are the other symptoms of pemphigus?
Nail changes
Burst gingival, buccal, and palatine bullae that are painful and slow healing.
Conjunctivae, oesophagus, and genitalia
How is pemphigus definitively diagnosed?
Skin biopsy from the edge of a blister, histology and DIF/IDIF
ELISAs for DSG1 and DSG3 in serum
What are the three phases of management of pemphigus?
Control, consolidation, maintenance.
What are the treatment options in the control phase of pemphigus management?
PO prednisolone
2nd line: plasmaphresis 3xw w/ azathioprine or cyclophosphamide
3rd line: IVIG
Describe the consolidation and maintenance phases of management of pemphigus.
Step down regime and tapering after 80% lesions have healed
Steroid sparing agents sometimes used to further reduce dose
What are the complications of pemphigus?
Secondary infection
Effects of corticosteroids
Malignancy immunosuppression
Give four differences between pemphigus and bullous pemphigoid
Pemphigus: younger, flaccid epidermal bullae, not pruritic
Pemphigoid: Older, tense subepidermal bullae, pruritic
What is lichen planus?
A pruritic, popular eruption characterized by its violaceous colour and polygonal shape.
What are the five Ps of lichen planus?
Purple Pruritic Polyangular Planus (flat-topped) Papules
Where is the rash of lichen planus found?
Flexor surfaces of extremities, upper>lower
Genitalia
Mucous membranes
What are some characteristic signs of lichen planus?
Lacy white lesions on mucous membranes
Intensely itchy 2-5mm red/violet shiny flat-topped papular with Wickham’s Striae
What occurs when papules clear in lichen planus?
They are replaced by brown discolouration
What are the nail and scalp changes seen in lichen planus?
Longitudinal ridges
Scarring alopecia
What are the potential causes of lichen planus?
T-cell mediated
Kobner’s phenomenon
RF: hepatitis C, PBC, female
What are the variations of lichen sclerosis?
Hypertrophic Atrophic Erosive/ulcerative Follicular Vesicular/bullous
What is seen on skin biopsy and histology in lichen planus?
Saw tooth pattern of epidermal hyperplasia and vacuolar alteration of the epidermis
T lymphohistioctic infiltration
Reduced melanocytes - Wickham’s striae
Globular deposits of IgM
What is the treatment of lichen planus?
Symptomatic itch treatment - potent corticosteroids and topical antifungals
Psoralen and PUVA radiation treatment
Systemic steroids
What is lichen simplex chronicus?
Localized area of skin becomes thickened and leathery due to chronic rubbing
What is the treatment of lichen simplex chronicus?
Superpotent corticosteroid ointment
Less potent if genital skin
50% of melanomas result following which mutation?
BRAF V600 on C7q34
What are five risk factors for malignant melanoma?
Previous history of melanoma More than 100 naevi Sun exposure Skin type 1 or 2 Solar keratoses
Name three subtypes of malignant melanoma.
Lentigo maligna melanoma
Superficial melanoma
Nodular melanoma
What is the weighed 7 point checklist for suspicious moles?
Major features (2 pts):
- Change in size
- Irregular shape
- Irregular colour
Minor features (1pt):
- Largest diameter>7mm
- Inflammation
- Oozing
- Change in sensation
What score on the weighted 7 point checklist for moles indicates a 2ww referral?
3 or more
How is malignant melanoma diagnosed?
Full thickness excisional biopsy with lateral excision margin of 2mm normal skin
Sentinel lymph node biopsy
CT and MRI
What is the primary treatment of malignant melanoma?
Wide local excision
What are some other treatments in malignant melanoma?
Vitamin D supplementation
Topical imiquimod
Lymhadenectomy
Adjuvant radiotherapy
What biologic therapies can be used to treat BRAF V600 positive malignant melanoma?
Dabrafenib and vemurafenib
What is the Breslow thickness?
Depth of invasion of melanoma at diagnosis
Strongly correlates with survival
Where do squamous cell carcinomas arise from?
Keratinizing cells of the epidermis
What are the risk factors for SCC and BCC of the skin?
Chronic UVR exposure, skin types 1 and 2, previous history. immune deficiency
Name two pre-malignant conditions which may lead to SCCs.
Bowen’s disease
Solar keratoses
How do squamous cell carcinomas present?
Indurated nodular keratinizing or crusted tumour that may ulcerate
Mostly head and neck
Tumour may bleed
How is squamous cell carcinoma diagnosed?
Excisional biopsy with wide margins
If in a cosmetically sensitive area, can be incisional/punch biopsy
How are SCCs managed?
Curettage and cautery
Cryotherapy
Electrochemotherapy
What are the topical treatments of superficial SCC or pre cancerous lesions?
Imiquimod 5% cream
Fluorouracil (Efudix 5%) cream
Diclofenac gel
What is the name of the technique where excision of the skin lesion is carried out in stages and each stage checked histologically?
Moh’s micrography
Which cancer is Mohs’ micrography used more often for?
Basal cell carcinomas
What are basal cell carcinomas?
Slow growing locally invasive malignant epidermal skin tumours that are thought to arise from hair follicles
What are the features of Gorlin’s syndrome?
Basal cell naevus and multiple BCCS Cataracts Jaw cysts Pitting of the hands and soles Calcification of the falx cerebri
What do early lesions of BCCs look for?
Small
Translucent or pearly
May have a raised area with telangiectasia
What is a rodent ulcer?
A large nodular BCC with a necrotic centre
What are the 5 subtypes of BCCs?
Nodular Superficial Morphoeic/sclerosing Pigmented Basosquamous
What is the cause of psoriasis?
Skin is inflamed and proliferates at 10x the normal rate
T-lymphocyte driven disorder
What are the genetic components of psoriasis?
PSORS1-9 genetic loci
What are the trigger factors of psoriasis?
They activate the APC-dendritic or Langerhans cell. Trauma UV light Beta blockers Infection Smoking/alcohol
What is the most common type of psoriasis?
Chronic plaque
How does Kobner Phenomenon feature in psoriasis?
New plaques at the site of trauma
When does flexural psoriasis present?
In later life
What are the features of guttate psoriasis?
Raindrop like plaques on trunk
Children
2 weeks post strep throat
What is the name of the most severe form of psoriasis?
Erythrodermic and pustular
What are the systemic features of erythrodermic/pustular psoriasis?
Malaise
Pyrexia
Circulatory disturbance
What are the associated nail features of erythrodermic/pustular psoriasis?
Nail pitting
Onycholysis
Subungal hyperkeratosis
7% of psoriasis patients develop a seronegative arthropathy. What are the different forms?
Mono/oligoarthritis Psoriatic spondylitis Asymmetrical polyarthritis Rheumatoid like polyarthritis Arthritis mutilans
What is the first line treatment of psoriasis?
Potent corticosteroid OF and Vit D analogue OD
e.g. betamethasone and calcitrol
Applied separately - one in the morning and one in evening
What is the second line treatment of psoriasis?
As above but Vit D analogue BD
What is the third line treatment of psoriasis?
Potent corticosteroid BD and vit D analogue BD
OR add coal tar to the above
What are the indications for referral in psoriasis?
Child or young person
Psoriasis is severe or covers 10% of body
Uncontrolled
Acute guttate psoriasis - requires phototherapy
What are some other treatments of psoriasis that can be initiated in secondary care?
Phototherapy (narrow band ultraviolent B (UVB) therapy)
Methotrexate
Infliximab/adalimumab/Certolizumab pegol
Name five conditions which can cause alopecia.
Seborrheic dermatitis Lichen planus Discoid SLE Iron deficiency Thyroid disease
What are some possible over the counter or private treatments for androgenetic alopecia in males?
Minoxidil topical
Finasteride PO
What is alopecia areata?
A chronic inflammatory disease which affects hair follicles and sometimes nails
What is pathognomic of alopecia areata?
Exclamation mark hairs
How is alopecia areata managed?
Spontaneous self resolution in 80%
Topical potent/very potent steroid
Some dermatologists may consider topical immunotherapy or minoxidil, or PUVA therapy
What is telogen effluvium?
Hair loss caused by physiological or hormonal stress
Hair is triggered to move into the telogen (dormant) phase
Give three causes of telogen effluvium.
Childbirth
Crash dieting/anorexia
Severe infection
What is the treatment of telogen effluvium?
Treat the cause and hair will return in a matter of months
What is the name of the condition where hair production is arrested in the anagen phase, caused by chemotherapy or radiotherapy?
Anagen effluvium
What is the management of burns?
IV fluid if burns>15% body surface area (10% if child)
Analgesia and urinary catheter
Escharotomy if circumferential burns
Excision and skin grafting
What are some complications of burns?
Curling's stress ulcer Rhabdomyolysis Compartment syndrome DIC Respiratory failure
What does dermatitis herpetiformis look like?
Itchy, vesicular lesions on the extensor surfaces e.g. elbows, knees, buttocks
How is dermatitis herpetiformis diagnosed?
Skin biopsy: DIF showed deposition of IgA in the upper dermis
How is dermatitis herpetiformis managed?
Dapsone
Gluten free diet (Coeliac’s)
What is acne rosacea?
Chronic skin disease of erythema, papules, and pustules, on the nose, cheeks, and forehead
Rhinophyma
What is the treatment of acne rosacea?
Topical metronidazole
Severe: oral tetracycline
What is the treatment of actinic keratoses?
Fluorouracil cream
Topical diclofenac
Topical imiquimod
What are the causes of erythema nodosum?
Sarcoidosis
Pregnancy
Drugs
IBD
What are the symptoms of hereditary haemorrhagic telangiectasia?
Pulmonary, hepatic, cerebral, and spinal AVMs
Nosebleeds, haemoptysis and dyspnoea, anaemia
