Dermatology

Question 1

Most important Prognostic factor with malignant melanoma

Answer 1

Depth Breslow depth under 1mm 95% 5yr survival Down to above 4mm is 50%

Question 2

Scoring criteria for malignant melanoma

Answer 2

Glasgow scale 3or above to refer Major - change in size, shape, colour Minor - inflam / crusting / bleeding / sensory change / diam over 7mm

Question 3

Multiple Small crusty lesion on top of head Old crusty man head

Answer 3

Actinic keratosis… Pre malig (SCC) prevent future risk,.. Fluoro cream (can give hydrocortisone too to settle inflam)

Question 4

Diagnosis

Answer 4

Actinic Keratosis

Question 5

diagnosis

Answer 5

SCC

Question 6

diagnosis

Answer 6

BCC (pearly, flesh-coloured papule with telangiectasia)

Question 7

diagnosis and causes

Answer 7

• Stevens-Johnson syndrome severe form of erythema multiforme associated with mucosal involvement and systemic symptoms
• rash is typically maculopapular with target lesions being characteristic. May develop into vesicles or bullae

Causes

• idiopathic
• bacteria: Mycoplasma, Streptococcus
• viruses: herpes simplex virus, Orf
• drugs: penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill
• connective tissue disease e.g. SLE
• sarcoidosis
• malignancy

Question 8

diagnosis, features, and causes

Answer 8

erythema multiform

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

Usually HSV

Question 9

child with conjuctivitis and maculopapular rash behind ears, progresses to this blotchy body rash.

Diagnosis, and what four bad complications?

Answer 9

measles

can have koplik spots on mouth too

Complications

• encephalitis: typically occurs 1-2 weeks following the onset of the illness)
• febrile convulsions
• giant cell pneumonia
• keratoconjunctivitis, corneal ulceration

Question 10

Diagnosis

Answer 10

Erythema infectiosum (also known as fifth disease or ‘slapped-cheek syndrome’)

Question 11

diagnosis description and associated conditions (5 categories)

Answer 11

Erythema nodosum

Overview

• inflammation of subcutaneous fat
• typically causes tender, erythematous, nodular lesions
• usualyl resolves with no scars in 6 weeks

Associated with…

• infection: streptococci, TB, brucellosis
• systemic disease: sarcoidosis, inflammatory bowel disease, Behcet’s
• malignancy/lymphoma
• drugs: penicillins, sulphonamides, combined oral contraceptive pill
• pregnancy

Question 12

Most common skin cancer

Answer 12

BCC.

• 3 out of 10 Caucasians develop BCC
• 80% found on the head and neck
• rarely metastasise or kill

Question 13

Description and Diagnosis

Answer 13

Paget’s disease of the nipple

• Itchy red scaly or crusted nipple, from intraductal breast cancer (mass in 50%)
• associated with an underlying mass lesion and 90% of such patients will have an invasive carcinoma

Question 14

Paget’s disease of nipple vs eczema…

Answer 14

Paget’s has well demarcated edge

Question 15

Drugs that can precipitate psoriasis

Answer 15

• beta blockers
• lithium
• antimalarials (chloroquine and hydroxychloroquine)
• NSAIDs
• ACEi
• infliximab

Question 16

diagnose

Answer 16

Keratoacanthoma

• benign epithelial tumour
• more frequent in middle age
• Need to exclude SCC

Question 17

What is this condition associated with

Answer 17

Erythema Nodosum

• infection: streptococci, TB, brucellosis
• systemic disease: sarcoidosis, inflammatory bowel disease, Behcet’s
• malignancy/lymphoma
• drugs: penicillins, sulphonamides, combined oral contraceptive pill
• pregnancy

Question 18

A 4-year-old boy develops multiple tear-drop papules on his trunk and limbs. He is otherwise well. A diagnosis of guttate psoriasis is suspected. What is the most appropriate management?

Answer 18

• Usually self limiting (6 weeks or so)

So

• Reassurance + topical treatment if lesions are symptomatic

Question 19

Top differential

Answer 19

Pityriasis rosea (could be guttate psoriasis… both self-limiting. Guttate preceded by strep sore throat 2-4 weeks)

On image:

• herald patch (usually on trunk)
• followed by erythematous, oval, scaly patches which follow a characteristic distribution with the longitudinal diameters of the oval lesions running parallel to the line of Langer. This may produce a ‘fir-tree’ appearance

Question 20

Two types of contact dermatitis

Answer 20

• irritant contact dermatitis: common - non-allergic reaction due to weak acids or alkalis (e.g. detergents). Often seen on the hands. Erythema is typical, crusting and vesicles are rare
• allergic contact dermatitis: type IV hypersensitivity reaction. Uncommon - often seen on the head following hair dyes. Presents as an acute weeping eczema which predominately affects the margins of the hairline rather than the hairy scalp itself. Topical treatment with a potent steroid is indicated

Question 21

What is this rash?

Answer 21

Erythema Multiforme

Associated with

• viruses: herpes simplex virus (the most common cause)
• idiopathic
• bacteria: Mycoplasma, Streptococcus
• drugs: penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill, nevirapine
• connective tissue disease e.g. SLE
• sarcoidosis
• malignancy

Question 22

Management

Answer 22

Seborrhoeic keratoses

• variation in colour
• stuck on appearance
• Reassure

options for removal include curettage, cryosurgery and shave biopsy

Question 23

Appropriate test following anaphylaxis to investigate the cause of the reaction?

Answer 23

• Radioallergosorbent test (RAST)
• (tests IgE