COR
REC
T
DERMATOLOGY
Question 1
A 62-year-old female is referred to dermatology due to a lesion over her shin. It initially started as a small red papule which
later became a deep, red, necrotic ulcers with a violaceous border. What is the likely diagnosis?
A. Necrobiosis lipoidica diabeticorum
B. Syphilis
C. Erythema nodosum
D. Pretibial myxoedema
E. Pyoderma gangrenosum
This is a classic description of pyoderma gangrenosum
Shin lesions
The differential diagnosis of shin lesions includes the following conditions:
erythema nodosum
pretibial myxoedema
pyoderma gangrenosum
necrobiosis lipoidica diabeticorum
Below are the characteristic features:
Erythema nodosum
symmetrical, erythematous, tender, nodules which heal without scarring
most common causes are streptococcal infections, sarcoidosis, inflammatory bowel disease and drugs (penicillins,
sulphonamides, oral contraceptive pill)
Pretibial myxoedema
symmetrical, erythematous lesions seen in thyrotoxicosis shiny, orange peel skin
Pyoderma gangrenosum
initially small red papule
later deep, red, necrotic ulcers with a violaceous border
idiopathic in 50%, may also be seen in inflammatory bowel disease, connective tissue disorders and myeloproliferative
disorders
Necrobiosis lipoidica diabeticorum
shiny, painless areas of yellow/red skin typically on the shin of diabetics often associated with surrounding telangiectasia
Question 2
A 30-year-old female in her third trimester of pregnancy mentions during an antenatal appointment that she has noticed an
itchy rash around her umbilicus. This is her second pregnancy and she had no similar problems in her first pregnancy.
Examination reveals blistering lesions in the peri-umbilical region and on her arms. What is the likely diagnosis?
A. Seborrhoeic dermatitis
B. Pompholyx
C. Polymorphic eruption of pregnancy
D. Lichen planus
E. Pemphigoid gestationis
Polymorphic eruption of pregnancy is not associated with blistering
Pemphigoid gestationis is the correct answer. Polymorphic eruption of pregnancy is not associated with blistering
Skin disorders associated with pregnancy
,Polymorphic eruption of pregnancy
pruritic condition associated with last trimester
lesions often first appear in abdominal striae
management depends on severity: emollients, mild potency topical steroids and oral steroids may be used
Pemphigoid gestationis
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 3
A 74-year-old lady with a history of hypothyroidism presents in January with a rash down the right side of her body. On
examination an erythematous rash with patches of hyperpigmentation and telangiectasia is found. What is the likely
diagnosis?
A. Erythema marginatum
B. Herpes zoster
C. Pretibial myxoedema
D. Erythema ab igne
E. Xanthomata
This is a classic presentation of erythema ab igne. Despite the name, pretibial myxoedema is associated with
hyperthyroidism rather than hypothyroidism
Erythema ab igne is a skin disorder caused by over exposure to infrared radiation. Characteristic features include
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 4
A 19-year-old student presents with a three day history of a 1 cm golden, crusted lesion on the border of her lower lip.
What is the most suitable management?
A. Oral co-amoxiclav
B. Oral penicillin
C. Oral flucloxacillin
D. Oral flucloxacillin + penicillin
E. Topical fusidic acid
Impetigo - topical fusidic acid --> oral flucloxacillin / topical mupirocin
This history is typical of impetigo. As the lesion is small and localised topical fusidic acid is recommended
Impetigo: management
Limited, localised disease
topical fusidic acid is first-line
topical mupirocin is used second-line if fusidic acid has been ineffective or is not tolerated
Extensive disease
oral flucloxacillin
oral erythromycin if penicillin allergic
Question 5
A 54-year-old man is referred to the dermatology outpatient department due to a facial rash which has persisted for the past
12 months. On examination there is a symmetrical rash consisting of extensive pustules and papules which affects his nose,
cheeks and forehead. What is the most appropriate treatment?
A. Ciprofloxacin
B. Isotretinoin
C. Oxytetracycline
D. Hydroxychloroquine
E. Prednisolone
As there is extensive involvement oral oxytetracycline should probably be used rather than topical metronidazole
Acne rosacea is a chronic skin disease of unknown aetiology
Features
typically affects nose, cheeks and forehead
flushing is often first symptom
later develops into persistent erythema with papules and pustules
rhinophyma
ocular involvement: blepharitis
Management
topical metronidazole may be used for mild symptoms (i.e. limited number of papules and pustules, no plaques)
more severe disease is treated with systemic antibiotics e.g. oxytetracycline
recommend daily application of a high-factor sunscreen
camouflage creams may help conceal redness
, laser therapy may be appropriate for patients with prominent telangiectasia
Question 6
A 22-year-old woman presents due to hypopigmented skin lesions on her chest and back. She has recently returned from
the south of France and has tanned skin. On examination the lesions are slightly scaly. What is the most likely diagnosis?
A. Tinea corporis
B. Pityriasis versicolor
C. Porphyria cutanea tarda
D. Lyme disease
E. Psoriasis
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)
scale is common
mild pruritus
Predisposing factors
occurs in healthy individuals
immunosuppression
malnutrition
Cushing's
Management
topical antifungal e.g. terbinafine or selenium sulphide
if extensive disease or failure to respond to topical treatment then consider oral itraconazole
Question 7
A 67-year-old man with a history of Parkinson's disease presents due to the development of an itchy, red rash on his neck,
behind his ears and around the nasolabial folds. He had a similar flare up last winter but did not seek medical attention.
What is the most likely diagnosis?
A. Levodopa associated dermatitis
B. Seborrhoeic dermatitis
C. Flexural psoriasis
D. Acne rosacea
E. Fixed drug reaction to ropinirole
Seborrhoeic dermatitis is more common in patients with Parkinson's disease
Seborrhoeic dermatitis in adults is a chronic dermatitis thought to be caused by an inflammatory reaction related to a
proliferation of a normal skin inhabitant, a fungus called Malassezia (formerly known as Pityrosporum ovale). It is
common, affecting around 2% of the general population
Features
eczematous lesions on the sebum-rich areas: scalp (may cause dandruff),
periorbital, auricular and nasolabial folds
otitis externa and blepharitis may develop
Associated conditions include
HIV
Parkinson's disease
Scalp disease management
over the counter preparations containing zinc pyrithione ('Head & Shoulders') and tar ('Neutrogena T/Gel') are first-line
the preferred second-line agent is ketoconazole
selenium sulphide and topical corticosteroid may also be useful
Face and body management
topical antifungals: e.g. ketoconazole
topical steroids: best used for short periods
difficult to treat - recurrences are common
REC
T
DERMATOLOGY
Question 1
A 62-year-old female is referred to dermatology due to a lesion over her shin. It initially started as a small red papule which
later became a deep, red, necrotic ulcers with a violaceous border. What is the likely diagnosis?
A. Necrobiosis lipoidica diabeticorum
B. Syphilis
C. Erythema nodosum
D. Pretibial myxoedema
E. Pyoderma gangrenosum
This is a classic description of pyoderma gangrenosum
Shin lesions
The differential diagnosis of shin lesions includes the following conditions:
erythema nodosum
pretibial myxoedema
pyoderma gangrenosum
necrobiosis lipoidica diabeticorum
Below are the characteristic features:
Erythema nodosum
symmetrical, erythematous, tender, nodules which heal without scarring
most common causes are streptococcal infections, sarcoidosis, inflammatory bowel disease and drugs (penicillins,
sulphonamides, oral contraceptive pill)
Pretibial myxoedema
symmetrical, erythematous lesions seen in thyrotoxicosis shiny, orange peel skin
Pyoderma gangrenosum
initially small red papule
later deep, red, necrotic ulcers with a violaceous border
idiopathic in 50%, may also be seen in inflammatory bowel disease, connective tissue disorders and myeloproliferative
disorders
Necrobiosis lipoidica diabeticorum
shiny, painless areas of yellow/red skin typically on the shin of diabetics often associated with surrounding telangiectasia
Question 2
A 30-year-old female in her third trimester of pregnancy mentions during an antenatal appointment that she has noticed an
itchy rash around her umbilicus. This is her second pregnancy and she had no similar problems in her first pregnancy.
Examination reveals blistering lesions in the peri-umbilical region and on her arms. What is the likely diagnosis?
A. Seborrhoeic dermatitis
B. Pompholyx
C. Polymorphic eruption of pregnancy
D. Lichen planus
E. Pemphigoid gestationis
Polymorphic eruption of pregnancy is not associated with blistering
Pemphigoid gestationis is the correct answer. Polymorphic eruption of pregnancy is not associated with blistering
Skin disorders associated with pregnancy
,Polymorphic eruption of pregnancy
pruritic condition associated with last trimester
lesions often first appear in abdominal striae
management depends on severity: emollients, mild potency topical steroids and oral steroids may be used
Pemphigoid gestationis
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 3
A 74-year-old lady with a history of hypothyroidism presents in January with a rash down the right side of her body. On
examination an erythematous rash with patches of hyperpigmentation and telangiectasia is found. What is the likely
diagnosis?
A. Erythema marginatum
B. Herpes zoster
C. Pretibial myxoedema
D. Erythema ab igne
E. Xanthomata
This is a classic presentation of erythema ab igne. Despite the name, pretibial myxoedema is associated with
hyperthyroidism rather than hypothyroidism
Erythema ab igne is a skin disorder caused by over exposure to infrared radiation. Characteristic features include
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 4
A 19-year-old student presents with a three day history of a 1 cm golden, crusted lesion on the border of her lower lip.
What is the most suitable management?
A. Oral co-amoxiclav
B. Oral penicillin
C. Oral flucloxacillin
D. Oral flucloxacillin + penicillin
E. Topical fusidic acid
Impetigo - topical fusidic acid --> oral flucloxacillin / topical mupirocin
This history is typical of impetigo. As the lesion is small and localised topical fusidic acid is recommended
Impetigo: management
Limited, localised disease
topical fusidic acid is first-line
topical mupirocin is used second-line if fusidic acid has been ineffective or is not tolerated
Extensive disease
oral flucloxacillin
oral erythromycin if penicillin allergic
Question 5
A 54-year-old man is referred to the dermatology outpatient department due to a facial rash which has persisted for the past
12 months. On examination there is a symmetrical rash consisting of extensive pustules and papules which affects his nose,
cheeks and forehead. What is the most appropriate treatment?
A. Ciprofloxacin
B. Isotretinoin
C. Oxytetracycline
D. Hydroxychloroquine
E. Prednisolone
As there is extensive involvement oral oxytetracycline should probably be used rather than topical metronidazole
Acne rosacea is a chronic skin disease of unknown aetiology
Features
typically affects nose, cheeks and forehead
flushing is often first symptom
later develops into persistent erythema with papules and pustules
rhinophyma
ocular involvement: blepharitis
Management
topical metronidazole may be used for mild symptoms (i.e. limited number of papules and pustules, no plaques)
more severe disease is treated with systemic antibiotics e.g. oxytetracycline
recommend daily application of a high-factor sunscreen
camouflage creams may help conceal redness
, laser therapy may be appropriate for patients with prominent telangiectasia
Question 6
A 22-year-old woman presents due to hypopigmented skin lesions on her chest and back. She has recently returned from
the south of France and has tanned skin. On examination the lesions are slightly scaly. What is the most likely diagnosis?
A. Tinea corporis
B. Pityriasis versicolor
C. Porphyria cutanea tarda
D. Lyme disease
E. Psoriasis
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)
scale is common
mild pruritus
Predisposing factors
occurs in healthy individuals
immunosuppression
malnutrition
Cushing's
Management
topical antifungal e.g. terbinafine or selenium sulphide
if extensive disease or failure to respond to topical treatment then consider oral itraconazole
Question 7
A 67-year-old man with a history of Parkinson's disease presents due to the development of an itchy, red rash on his neck,
behind his ears and around the nasolabial folds. He had a similar flare up last winter but did not seek medical attention.
What is the most likely diagnosis?
A. Levodopa associated dermatitis
B. Seborrhoeic dermatitis
C. Flexural psoriasis
D. Acne rosacea
E. Fixed drug reaction to ropinirole
Seborrhoeic dermatitis is more common in patients with Parkinson's disease
Seborrhoeic dermatitis in adults is a chronic dermatitis thought to be caused by an inflammatory reaction related to a
proliferation of a normal skin inhabitant, a fungus called Malassezia (formerly known as Pityrosporum ovale). It is
common, affecting around 2% of the general population
Features
eczematous lesions on the sebum-rich areas: scalp (may cause dandruff),
periorbital, auricular and nasolabial folds
otitis externa and blepharitis may develop
Associated conditions include
HIV
Parkinson's disease
Scalp disease management
over the counter preparations containing zinc pyrithione ('Head & Shoulders') and tar ('Neutrogena T/Gel') are first-line
the preferred second-line agent is ketoconazole
selenium sulphide and topical corticosteroid may also be useful
Face and body management
topical antifungals: e.g. ketoconazole
topical steroids: best used for short periods
difficult to treat - recurrences are common
