Dermatology Flashcards
yellow nail syndrome associated with (4)
pleural effusions
bronchiectasis
chronic sinus infections
congenital lymphoedema
Causes of Stevens-Johnson syndrome
penicillin
sulphonamides
lamotrigine, carbamazepine, phenytoin
allopurinol
NSAIDs
oral contraceptive pill
Treatment of TEN
- stop precipitating factor
- supportive care
- Iv ig has been shown to be effective and is now commonly used first-line
- immunosuppressive agents (ciclosporin and cyclophosphamide),
- plasmapheresis
Treatment of SJS
hospital admission is required for supportive treatment
Pemphigus vulgaris is an autoimmune disease caused by antibodies directed against….
desmoglein 3, a cadherin-type epithelial cell adhesion molecule
mucosal ( ulceration ) involvement
In Bullous pemphigoid or Pemphigus vulgaris?
Pemphigus vulgaris
Pemphigus vulgaris is more common in the ……. population.
Ashkenazi Jewish
3 Features of Pemphigus vulgaris
- mucosal ulceration
- skin blistering
- acantholysis on biopsy
Treatment of Pemphigus vulgaris
steroids are first-line
immunosuppressants
Causes of Onycholysis
idiopathic
trauma e.g. Excessive manicuring
infection: especially fungal
skin disease: psoriasis, dermatitis
impaired peripheral circulation e.g. Raynaud’s
hyper- and hypothyroidism
Bullous pemphigoid is secondary to the development of antibodies against …….
hemidesmosomal proteins BP180 and BP230
Bullous pemphigoid is more common in
elderly patients
Skin biopsy in Bullous pemphigoid
immunofluorescence shows IgG and C3 at the dermoepidermal junction
Treatment of Bullous pemphigoid
referral to a dermatologist for biopsy and confirmation of diagnosis
oral corticosteroids are the mainstay of treatment
topical corticosteroids, immunosuppressants and antibiotics are also used
Causative organisms of Fungal nail infection (onychomycosis)
- dermatophytes
account for around 90% of cases
mainly Trichophyton rubrum
- yeasts
account for around 5-10% of cases
e.g.Candida
- non-dermatophyte moulds
4 Risk factors of Fungal nail infection (onychomycosis)
increasing age
diabetes mellitus
psoriasis
repeated nail trauma
Investigation of fungal nail infection
nail clippings +/- scrapings of the affected nail
Treatment of fungal nail infection
- do not need to be treated if it is asymptomatic
- dermatophyte or Candida infection is confirmed
- limited involvement (‰¤50% nail affected, ‰¤ 2 nails affected, more superficial white onychomycosis): topical treatment with amorolfine 5% nail lacquer; 6 months for fingernails and 9 - 12 months for toenails
- if more extensive involvement due to a dermatophyte infection:oral terbinafineis currently recommended first-line; 6 weeks - 3 months therapy is needed for fingernail infections whilst toenails should be treated for 3 - 6 months
- if more extensive involvement due to a Candida infection: oral itraconazole is recommended first-line; ‘pulsed’ weekly therapy is recommended
11 Causes of Acanthosis nigricans
- T2DM
- Cushing’s disease
- acromegaly
- hypothyroidism
- polycystic ovarian syndrome
- obesity
- gastrointestinal cancer
- familial
- Prader-Willi syndrome
- OCP
- nicotinic acid
Pathophysiology of Acanthosis nigricans
insulin resistance → hyperinsulinemia → stimulation of ……….. via interaction with insulin-like growth factor receptor-1 (IGFR1)
keratinocytes and dermal fibroblast proliferation
small, crusty or scaly, lesions
may be pink, red, brown or the same colour as the skin
typically on sun-exposed areas e.g. temples of head
multiple lesions may be present
Features of
Actinic, or solar, keratoses
Managment of Actinic, or solar, keratoses
prevention of further risk: e.g. sun avoidance, sun cream
fluorouracil cream: typically a 2 to 3 week course. The skin will become red and inflamed - sometimes topical hydrocortisone is given following fluorouracil to help settle the inflammation
topical diclofenac: may be used for mild AKs. Moderate efficacy but much fewer side-effects
topical imiquimod: trials have shown good efficacy
cryotherapy
curettage and cautery
5 Causes of Scarring alopecia
trauma, burns
radiotherapy
lichen planus
tinea capitis
discoid lupus
- Tom really likes To do scarring alopecia
Causes of Non-scarring alopecia
male-pattern baldness
drugs: cytotoxic drugs, carbimazole, heparin, oral contraceptive pill, colchicine
nutritional: iron and zinc deficiency
autoimmune: alopecia areata
telogen effluvium
hair loss following stressful period e.g. surgery
trichotillomania
Management of Basal cell carcinoma
surgical removal
curettage
cryotherapy
topical cream: imiquimod, fluorouracil
radiotherapy
Dermatitis herpetiformis caused by deposition of …..
IgA in the dermis
Diagnosis of Dermatitis herpetiformis
skin biopsy: direct immunofluorescence shows deposition of IgA in a granular pattern in the upper dermis
Treatment of Dermatitis herpetiformis
gluten-free diet
dapsone
Erythema ab igne If not treated then patients may go on to develop …..
squamous cell skin cancer
Erythema ab igne is a skin disorder caused by over exposure to …..
infrared radiation
Causes of erythroderma
eczema
psoriasis
drugs e.g. gold
lymphomas, leukaemias
idiopathic
- Every person goes 2 look inside erythroderma
Erythrodermic psoriasis may be triggered by
withdrawal of systemic steroids
Erythrasma is a generally asymptomatic, flat, slightly scaly, pink or brown rash usually found in …..
the groin or axillae
Erythrasma is caused by an overgrowth of
diphtheroid Corynebacterium minutissimum
Wood’s light reveals a coral-red fluorescence.
Seen in
Erythrasma
Treatment of Erythrasma
Topical miconazole or antibacterial are usually effective.
Oral erythromycin may be used for more extensive infection
Erythema nodosum usually resolves within …
6 weeks
5 main Causes of Erythema nodosum
- infection
streptococci
tuberculosis
brucellosis
- systemic disease
sarcoidosis
inflammatory bowel disease
Behcet’s
- malignancy/lymphoma
- drugs
penicillins
sulphonamides
combined OCP
- pregnancy
Erythema multiforme is a hypersensitivity reaction that is most commonly triggered by ……
infections
In Erythema multiforme, the upper limbs are ….
more commonly affected than the lower limbs
Causes of erythema multiforme
- Viruses: HSV , Orf
- Bacteria: Mycoplasma,Streptococcus
- sarcoidosis
- malignancy
- connective tissue disease e.g. Systemic lupus erythematosus
- drugs: penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill, nevirapine
The more severe form, erythema multiforme major is associated with
mucosal involvement.
Eczema herpeticum is a severe primary infection of the skin by
herpes simplex virus1 or 2
And uncommonly Coxsackievirus
Eczema herpeticum, the rash is characterized by
rapidly progressing painful rash
monomorphic punched-out erosions (circular, depressed, ulcerated lesions) usually 1-3 mm in diameterare typically seen in …….
Eczema herpeticum
Treatment of Eczema herpeticum
Admission
Iv acyclovir
dermatitis artefacta is strongly associated with
personality disorder, dissociative disorders and eating disorders
Acrodermatitis enteropathica is a ……. inherited partial defect in intestinal zinc absorption.
recessively
acrodermatitis
alopecia
short stature
hypogonadism
hepatosplenomegaly
geophagia (ingesting clay/soil)
cognitive impairment
Features of…
Zinc deficiency
Vitiligo is an autoimmune condition which results in the loss of ………. and consequent depigmentation of the skin
melanocytes
Vitiligo is associated with
type 1 diabetes mellitus
Addison’s disease
autoimmune thyroid disorders
pernicious anaemia
alopecia areata
Management vitiligo
sunblock for affected areas of skin
camouflage make-up
topical corticosteroids may reverse the changes if applied early
there may also be a role for topical tacrolimus and phototherapy, although caution needs to be exercised with light-skinned patients
ankle-brachial pressure index (ABPI)
1. Normal value …?
2. Below normal value indicates….?
3. Above the normal value indicates ….?
- 0.9 - 1.2
- indicate arterial disease
- indicate arterial disease, in the form of false-negative results secondary to arterial calcification (e.g. In diabetics)
Treatment of Venous ulceration
- compression bandaging, usually four layer (only treatment shown to be of real benefit)
- oral pentoxifylline, a peripheral vasodilator, improves healing rate
immune complex small-vessel vasculitis
- Henoch-Schonlein purpura
- Goodpasture’s syndrome (anti-glomerular basement membrane disease)
- cryoglobulinaemic vasculitis
- hypocomplementemic urticarial vasculitis (anti-C1q vasculitis)
Systemic mastocytosis results from a neoplastic proliferation of ….
mast cells
Features and Systemic mastocytosis
- urticaria pigmentosa - produces a wheal on rubbing (Darier’s sign)
- flushing
- abdominal pain
- monocytosis on the blood film
Diagnosis of Systemic mastocytosis
raised serum tryptase levels
urinary histamine