Dermatology MCQs - revision questions
and materials
Medicine and surgery (University of Nairobi)
,Question 1 of 121
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
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 Graves' disease
• 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 telangiectasia
1
,Question 2 of 121
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
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
2
, Question 3 of 121
A 25-year-old man presents with a widespread rash over his body. The torso
and limbs are covered with multiple erythematous lesions less than 1 cm in
diameter which in parts are covered by a fine scale. You note that two weeks
earlier he was seen with to a sore throat when it was noted that he had
exudative tonsillitis. Other than a history of asthma he is normally fit and
well. What is the most likely diagnosis?
A. Pityriasis Rosea
B. Pityriasis versicolor
C. Syphilis
D. Discoid eczema
E. Guttate psoriasis
E. Guttate psoriasis
Psoriasis: guttate
.............................................
Guttate psoriasis is more common in children and adolescents. It may be
precipitated by a streptococcal infection 2-4 weeks prior to the lesions
appearing
Features
• tear drop papules on the trunk and limbs
Management
• most cases resolve spontaneously within 2-3 months
• there is no firm evidence to support the use of antibiotics to eradicate
streptococcal infection
• topical agents as per psoriasis
• UVB phototherapy
• tonsillectomy may be necessary with recurrent episodes
3
and materials
Medicine and surgery (University of Nairobi)
,Question 1 of 121
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
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 Graves' disease
• 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 telangiectasia
1
,Question 2 of 121
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
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
2
, Question 3 of 121
A 25-year-old man presents with a widespread rash over his body. The torso
and limbs are covered with multiple erythematous lesions less than 1 cm in
diameter which in parts are covered by a fine scale. You note that two weeks
earlier he was seen with to a sore throat when it was noted that he had
exudative tonsillitis. Other than a history of asthma he is normally fit and
well. What is the most likely diagnosis?
A. Pityriasis Rosea
B. Pityriasis versicolor
C. Syphilis
D. Discoid eczema
E. Guttate psoriasis
E. Guttate psoriasis
Psoriasis: guttate
.............................................
Guttate psoriasis is more common in children and adolescents. It may be
precipitated by a streptococcal infection 2-4 weeks prior to the lesions
appearing
Features
• tear drop papules on the trunk and limbs
Management
• most cases resolve spontaneously within 2-3 months
• there is no firm evidence to support the use of antibiotics to eradicate
streptococcal infection
• topical agents as per psoriasis
• UVB phototherapy
• tonsillectomy may be necessary with recurrent episodes
3
