derm Flashcards
A 22 year old man attends the GP with a rash on his foot.
He first noticed it 3 weeks ago and it has not been improving. He is otherwise well with no relevant past medical history.
On examination there is a large, erythematous, scaly patch across 3 toes and part of the dorsum of his left foot. There is an area of central clearing and the outer edge appears most inflamed.
Which of the following is the most likely diagnosis?
tinea pedis - athletes foot
what is this slow growing lesion
Seborrhoeic Keratosis
treatment
Emollient/Topical Clotrimazole 1%
This patient has infantile seborrheoic dermatitis without signs of any inflammation of the scalp. A combination of emollients and clotrimazole 1% cream is the first line. Seborrheic dermatitis is usually caused by an overgrowth of the yeast Malassezia which is why antifungals can be effective.
A 64 year old patient with liver cirrhosis presents with mild ascites and is prescribed Spironolactone by her GP. Two days later, she notices an itchy, raised bullous rash that covers a large area of her body but spares the mucous membranes. The blisters are fluid-filled and are more densely propagated in skin flexures.
Given the most likely diagnosis, which of the following abnormalities is most likely to be found in this patient?
Antibodies against hemidesmosome proteins BP180 and BP230
The patient’s presentation is in keeping with Bullous Pemphigoid. Specifically, she has multiple fluid-filled blisters on skin flexures and the mucosal membranes are spared. Drugs that have been linked with Bullous Pemphigoid include: Spironolactone, Furosemide, Sulfasalazine, Penicillins, Beta-blockers, Antipsychotics and Enoxaparin. It is important to remember that Bullous Pemphigoid is an autoimmune condition, and a characteristic finding is autoantibodies against hemidesmosome proteins BP180 and BP230.
roasacea first line if severe
Rosacea: a combination of topical ivermectin + oral doxycycline is first-line for patients with severe papules and/or pustules
vulvar lichen sclerosus first line
topical steroids- clobetasol propionate, topical tacrolimus is next line, topical imiqimod can induce (is used for genital warts)
erythrasma abx
erythromycin
what
acanthosis nigricans
Describes symmetrical, brown, velvety plaques that are often found on the neck, axilla and groin.
Causes
type 2 diabetes mellitus
gastrointestinal cancer
obesity
polycystic ovarian syndrome
acromegaly
Cushing’s disease
hypothyroidism
familial
Prader-Willi syndrome
drugs
combined oral contraceptive pill
nicotinic acid
HSV can cause
erythema multiforme
what
acne rosacea
what
polymorphic eruption of pregnancy, third trimester, v itchy
anti streptolysin O titres raised and rash on legs
streptococcal infection causing erythema multiforme
man with pigmented lesion on palm most likely diagnosis- new and irregular borders and pigmentation
Acral lentiginous melanoma can arise in areas not associated with sun exposure e.g. soles of feet and palms
first degree burn
superficial epidermal - red and painful, dry, no blisters
second degree burn
partial thickness (superficial dermal) - red painful and blistered, slow cap refill
partial thickness (deep dermal) - white, patches of non blanching erythema, reduced sensation, painful to deep pressure
third degree burn
full thickness, white waxy brown leathery black, no blisters, no pain
uncircumcised man with tight white ring around tip of foreskin and phimosis diagnosis
lichen sclerosis
rosacea with predominant flushing but limited telangiectasia
brimonidine gel
blanching erythema means
superficial dermal
what
erythema ab igne - from hot water bottle
HIV facial rash
seborrhoea dermatitis - salmon pink thin scaly and ill defined plaques in skin folds
lip crusted ulcerated lesion management
mohs micrographic surgery due to SSC risk - in high risk patients and cosmetically important sites, minimises scarring
surgical excision 4mm vs 6mm
4mm for <2cm lesion, 6mm for >2cm lesion. Not cosmetically important sites
lithium may trigger
a psoriasis exacerbation
perioral dermatitis treatment
doxycycline
isoniazid, an anti Tb med, may induce
pellagra - which causes dermatitis
Four Ds of pellagra (vit B3) - diarrhoea, dermatitis, dementia, death
Seborrhoeic dermatitis - an inflammatory reaction to
Malassezia furfur
just started on allopurinol for gout, non pruritic, what is it
erythema multiforme
Features
target lesions
initially seen on the back of the hands / feet before spreading to the torso
upper limbs are more commonly affected than the lower limbs
pruritus is occasionally seen and is usually mild
drug causes of erythema multiform
penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill, nevirapine
renal transplant patients common malignancy secondary to immunosuppressed
Renal transplant patients - skin cancer (particularly squamous cell) is the most common malignancy secondary to immunosuppression
pt has SLE and coeliac
Plaque psoriasis is associated with erythematous plaques covered in a silvery-white scale that, when removed, exposes an underlying red membrane that can bleed known as Auspitz’s sign. In addition, this patient has a history of autoimmune diseases, which increases the chance of her developing another autoimmune disease.
not dermatitis herpetiforis as intensely itchy, papulovesicular rash with blisters (looks like herpes rash), not plaques
anterior blepharitis most common underlying cause
Otitis externa and blepharitis are common complications of seborrhoeic dermatitis
lichen planus vs sclerosus
planus - skin, (think plain)
sclerosus - vulva, (think scary)
fungal nail management after amorolfine nail lacquer has failed
oral terbinafine (check liver function)
what is it
oral leukoplakia - pre malignant hard white spots on mucous membranes, common in smokers
The asymptomatic and prolonged nature of the symptoms goes against a diagnosis of candidiasis. Lichen planus (rather than sclerosus) is a differential diagnosis but tends to have a slightly different appearance - typically a symmetrical white lace-like pattern on the buccal mucosa. Squamous cell carcinoma is not the most likely diagnosis as only around 1% of oral leukoplakias become malignant.
psoriasis with rash post vaccine
Koebner phenomenon
most effective treatment for prominent telangiectasia
laser therapy
A 62-year-old woman presents to her GP with an itchy rash of several weeks’ duration. She describes the rash as being present on her hands and around the elbows. She is otherwise well and has no past medical history except for hypertension.
On examination, a papular, polygonal, violaceous, flat-topped rash is present on the palms, in her elbow creases and on the soles of her feet.
Given the likely diagnosis, what is the first-line treatment?
potent topical steroids for lichen planus
A painful, rapidly growing ulcer with a violaceous or erythematous border
What is it, symptoms, causes, treatment and complications
