derm

Question 1

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?

Answer 1

tinea pedis - athletes foot

Question 2

what is this slow growing lesion

Answer 2

Seborrhoeic Keratosis

Question 3

treatment

Answer 3

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.

Question 4

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?

Answer 4

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.

Question 5

roasacea first line if severe

Answer 5

Rosacea: a combination of topical ivermectin + oral doxycycline is first-line for patients with severe papules and/or pustules

Question 6

vulvar lichen sclerosus first line

Answer 6

topical steroids- clobetasol propionate, topical tacrolimus is next line, topical imiqimod can induce (is used for genital warts)

Question 7

erythrasma abx

Answer 7

erythromycin

Question 8

what

Answer 8

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

Question 9

HSV can cause

Answer 9

erythema multiforme

Question 10

what

Answer 10

acne rosacea

Question 11

what

Answer 11

polymorphic eruption of pregnancy, third trimester, v itchy

Question 12

anti streptolysin O titres raised and rash on legs

Answer 12

streptococcal infection causing erythema multiforme

Question 13

man with pigmented lesion on palm most likely diagnosis- new and irregular borders and pigmentation

Answer 13

Acral lentiginous melanoma can arise in areas not associated with sun exposure e.g. soles of feet and palms

Question 14

first degree burn

Answer 14

superficial epidermal - red and painful, dry, no blisters

Question 15

second degree burn

Answer 15

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

Question 16

third degree burn

Answer 16

full thickness, white waxy brown leathery black, no blisters, no pain

Question 17

uncircumcised man with tight white ring around tip of foreskin and phimosis diagnosis

Answer 17

lichen sclerosis

Question 18

rosacea with predominant flushing but limited telangiectasia

Answer 18

brimonidine gel

Question 19

blanching erythema means

Answer 19

superficial dermal

Question 20

what

Answer 20

erythema ab igne - from hot water bottle

Question 21

HIV facial rash

Answer 21

seborrhoea dermatitis - salmon pink thin scaly and ill defined plaques in skin folds

Question 22

lip crusted ulcerated lesion management

Answer 22

mohs micrographic surgery due to SSC risk - in high risk patients and cosmetically important sites, minimises scarring

Question 23

surgical excision 4mm vs 6mm

Answer 23

4mm for <2cm lesion, 6mm for >2cm lesion. Not cosmetically important sites

Question 24

lithium may trigger

Answer 24

a psoriasis exacerbation

Question 25

perioral dermatitis treatment

Answer 25

doxycycline

Question 26

isoniazid, an anti Tb med, may induce

Answer 26

pellagra - which causes dermatitis

Four Ds of pellagra (vit B3) - diarrhoea, dermatitis, dementia, death

Question 27

Seborrhoeic dermatitis - an inflammatory reaction to

Answer 27

Malassezia furfur

Question 28

just started on allopurinol for gout, non pruritic, what is it

Answer 28

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

Question 29

drug causes of erythema multiform

Answer 29

penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill, nevirapine

Question 30

renal transplant patients common malignancy secondary to immunosuppressed

Answer 30

Renal transplant patients - skin cancer (particularly squamous cell) is the most common malignancy secondary to immunosuppression

Question 31

pt has SLE and coeliac

Answer 31

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

Question 32

anterior blepharitis most common underlying cause

Answer 32

Otitis externa and blepharitis are common complications of seborrhoeic dermatitis

Question 33

lichen planus vs sclerosus

Answer 33

planus - skin, (think plain)
sclerosus - vulva, (think scary)

Question 34

fungal nail management after amorolfine nail lacquer has failed

Answer 34

oral terbinafine (check liver function)

Question 35

what is it

Answer 35

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.

Question 36

psoriasis with rash post vaccine

Answer 36

Koebner phenomenon

Question 37

most effective treatment for prominent telangiectasia

Answer 37

laser therapy

Question 38

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?

Answer 38

potent topical steroids for lichen planus

Question 39

A painful, rapidly growing ulcer with a violaceous or erythematous border

What is it, symptoms, causes, treatment and complications

Answer 39