Dermatology

Question 1

What is Erythema Multiforme?

Answer 1

A hypersensitivity reaction that is most commonly triggered by infections. It may be divided into minor and major forms. Erythema multiforme major is associated with mucosal involvement.

Question 2

In patients with psoriasis, how long should they take a break from courses of topical corticosteroids?

Answer 2

4 week

Question 3

What are the features of Lichen planus?

Answer 3

• itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms
• rash often polygonal in shape, with a ‘white-lines’ pattern on the surface (Wickham’s striae)
• Koebner phenomenon may be seen (new skin lesions appearing at the site of trauma)
• oral involvement in around 50% of patients: typically a white-lace pattern on the buccal mucosa
• nails: thinning of nail plate, longitudinal ridging

Question 4

Features of pyoderma gangrenosum?

Answer 4

location: typically on the lower limb, often at the site of a minor injury as in this patient’s case and this is known as pathergy

initially features: usually starts quite suddenly, small pustule, red bump or blood-blister

later features: the skin then breaks down resulting in an ulcer which is often painful, the edge of the ulcer is often described as purple, violaceous and undermined.
the ulcer itself may be deep and necrotic

may be accompanied by systemic symptoms: fever, myalgia

Question 5

What areas are involved in Wallace’s Rule of Nine?

Answer 5

Each of the following is 9% of the body when calculating surface area % if a burn: 
Head + neck
each arm
each anterior part of leg
each posterior part of leg
anterior chest
posterior chest
anterior abdomen
posterior abdomen

Question 6

Management of Lichen Planus

Answer 6

• potent topical steroids are the mainstay of treatment
• benzydamine mouthwash or spray is recommended for oral lichen planus
• extensive lichen planus may require oral steroids or immunosuppression

Question 7

How long does the pityriasis rosea rash last?

Answer 7

6-12 weeks

Question 8

What is recommended antiviral use in shingles?

Answer 8

in practice, they recommend antivirals within 72 hours for the majority of patients, unless the patient is < 50 years and has a ‘mild’ truncal rash

associated with mild pain and no underlying risk factors
one of the benefits of prescribing antivirals is a reduced incidence of post-herpetic neuralgia, particularly in older people

aciclovir, famciclovir, or valaciclovir are recommended

Question 9

Classic symptoms of Seborrhoeic dermatitis

Answer 9

dandruff and eczematous lesions with flakes on the periorbital, auricular and nasolabial folds

otitis externa and blepharitis may develop

Question 10

What is the step-up management of acne?

Answer 10

1) single topical therapy (topical retinoids, benzoyl peroxide)
2) topical combinatiom therapy (topical antibiotic, benzoyl peroxide, topical retinoid)
3) oral antibiotics (tetracyclines, erythromycin in pregnancy) used for max. of three months. Topical retinoid or benzoyl peroxide should always be co-prescribed to reduce riso fo antibiotic resistance developing. Topical and oral antibiotics should not be used in combination. Gram-negative folliculitis may occur as complication of long-term antibiotic use (high dose oral trimethoprim is effective is this occurs)
4) COCP - alternative to oral antibiotics, should be used in combination with topical agents. Dianette sometimes used due to anti-androgen properties, however high risk of VTE so only given 3 months and women counselled about risks
5) oral isotretinoin - only under specialist supervision. Pregnancy is contraindication.

Question 11

What is Pityriasis versicolor?

Answer 11

Is a superficial cutaneous fungal infection caused by Malassezia furfur which usually presents on the trunk or back and is scaly is appearance.

Question 12

Inpatient treatment for erythroderma must be monitored for what complications?

Answer 12

Dehydration, infection and high-output heart failure

Question 13

What is erythema nodosum?

Answer 13

inflammation of subcutaneous fat
typically causes tender, erythematous, nodular lesions
usually occurs over shins, may also occur elsewhere (e.g. forearms, thighs)
usually resolves within 6 weeks
lesions heal without scarring

Question 14

What are causes of erythema nodosum?

Answer 14

infection (streptococci, tuberculosis, brucellosis)
systemic disease (sarcoidosis, inflammatory bowel disease, Behcet’s)
malignancy/lymphoma
drugs (penicillins, sulphonamides, combined oral contraceptive pill)
pregnancy

Question 15

What is Pityriasis versicolour?

Answer 15

Pityriasis versicolor, also called tinea versicolor, is a superficial cutaneous fungal infection caused by Malassezia furfur (formerly termed Pityrosporum ovale)

Features:
most commonly affects trunk
patches may be hypopigmented, pink or brown (hence versicolor). May be more noticeable following a suntan
scale is common
mild pruritus

Question 16

What triggers worsen psoriasis?

Answer 16

alcohol, smoking, stress, discontinuing steroids or initiating NSAIDs, lithium, antimalarials and beta-blockers

Question 17

Morphoeic BCC v Nodular BCC

Answer 17

associated more extensive spread than nodular BCC as it is more aggressive and often presents later

Question 18

Gold-standard treatment of Morphoeic BCC

Answer 18

Mohs microgaphic surgery

involves microscopic examination of excised tissue during the surgery. This is useful in tumours with poorly-defined edges to ensure that the whole tumour has been excised while minimising removal of healthy tissue.

Question 19

What is Erythema ab igne?

Answer 19

a skin disorder caused by over exposure to infrared radiation. Characteristic features include reticulated, erythematous patches with hyperpigmentation and telangiectasia. A typical history would be an elderly women who always sits next to an open fire.

If the cause is not treated then patients may go on to develop squamous cell skin cancer.

Question 20

What is toxic epidermal necrolysis?

Answer 20

is a potentially life-threatening skin disorder that is most commonly seen secondary to a drug reaction. In this condition, the skin develops a scalded appearance over an extensive area.

Question 21

What drugs can cause toxic epidermal necrolysis?

Answer 21

phenytoin
sulphonamides
allopurinol
penicillins
carbamazepine
NSAIDs

Question 22

Risk factors of SCC?

Answer 22

• excessive exposure to sunlight / psoralen UVA therapy
• actinic keratoses and Bowen’s disease
• immunosuppression e.g. following renal transplant, HIV
  smoking
• long-standing leg ulcers (Marjolin’s ulcer)
• genetic conditions e.g. xeroderma pigmentosum, oculocutaneous albinism

Question 23

Features of BCC?

Answer 23

many types of BCC are described. The most common type is nodular BCC, which is described here
sun-exposed sites, especially the head and neck account for the majority of lesions
initially a pearly, flesh-coloured papule with telangiectasia
may later ulcerate leaving a central ‘crater’

Question 24

Features of Hidradenitis suppurativa?

Answer 24

chronic, painful, inflammatory skin disorder. It is characterized by the development of inflammatory nodules, pustules, sinus tracts, and scars in intertriginous areas. It should be suspected in pubertal or post-pubertal patients who have a diagnosis of recurrent furuncles or boils, especially in intertriginous areas.

Question 25

Rosacea Treatment?

Answer 25

mild/moderate: topical metronidazole

severe/resistant: oral tetracycline

Question 26

First-line for hyperhidrosis?

Answer 26

Topical aluminium chloride

Question 27

What is features of Pemphigoid gestationis?

Answer 27

• pruritic blistering lesions
• often develop in peri-umbilical region, later spreading to the trunk, back, buttocks and arms
• usually presents 2nd or 3rd trimester and is rarely seen in the first pregnancy
  oral corticosteroids are usually required

Question 28

Where do Acral lentiginous melanomas arise from?

Answer 28

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

Question 29

Acne patients with scarring should be referred for?

Answer 29

Oral isotretinoin

Question 30

Common sites of keloid scars?

Answer 30

common sites (in order of decreasing frequency): sternum, shoulder, neck, face, extensor surface of limbs, trunk

Question 31

Features of Rosacea?

Answer 31

nose, cheeks and forehead

flushing, erythema, telangiectasia → papules and pustules

Question 32

Management of Dermatitis herpetiformis?

Answer 32

gluten-free diet

dapsone

Question 33

What bacteria contributes to the development of acne?

Answer 33

Propionibacterium acnes

Question 34

What is nodular melanoma?

Answer 34

Red or black lump, oozes or bleeds, sun-exposed skin

Question 35

What formula is used to calculate the volume of fluid required for resuscitation over the first 24 hours after the burn?

Answer 35

Parkland formula is used to calculate the volume of IV fluid required for resuscitation over the first 24 hours after the burn

Question 36

What size do you US a lipoma?

Answer 36

> 5cm

Question 37

What is alopecia areata?

Answer 37

presumed autoimmune condition causing localised, well demarcated patches of hair loss. At the edge of the hair loss, there may be small, broken ‘exclamation mark’ hairs

Question 38

First-line treatment for hyperhidrosis?

Answer 38

Aluminium chloride

Question 39

What are common complications of seborrhoeic dermatitis?

Answer 39

Otitis externa and blepharitis

Question 40

What skin disorders are seen in SLE?

Answer 40

Skin manifestations of systemic lupus erythematosus (SLE):

• photosensitive ‘butterfly’ rash
• discoid lupus
• alopecia
• livedo reticularis: net-like rash

Question 41

What skin manifestation is seen in Reiter’s syndrome

Answer 41

Keratoderma blenorrhagica - describes waxy yellow papules on the palms and soles

Question 42

What medication is known to exacerbate plaque psoriasis?

Answer 42

Beta-blockers