dermatology passmed

Question 1

what is Dermatitis herpetiformis?

Answer 1

• Dermatitis herpetiformis is an autoimmune blistering skin disorder associated with coeliac disease.
• It is caused by deposition of IgA in the dermis.

Question 2

What are the features of dermatitis herpetiformis?

Answer 2

• itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks)

Question 3

What is the diagnosis and managment of dermatitis herpetiformis?

Answer 3

Dagnosis → Skin biopsy. Immunofluorescence shows deposition of IgA in a granular pattern in the upper dermis

Tx → gluten-free diet, Dapsone (an Abx)

Question 4

What is a wide spread erythmatous rash that is comprised of tear drop papules on the trunk and limbs that are covered by a fine scale and is more common in children and adolescents, often preceded by a strptococcal infection?

Answer 4

Guttate psoriasis

Question 5

Name 4 shin lesions?

Answer 5

• Erythema nodosum
• Pretibial myxoedema
• Pyoderma gangrenosum
• Necrobiosis lipoidica diabeticorum

Question 6

Describe Erythema nodosum?

Answer 6

• Symmetrical, erythematous, tender, nodules which heal without scarring
• The nodules are slightly raised above the surrounding skin; they are hot and painful, bright red when they first appear, later becoming purple then fading through the colour changes of a bruise.

Question 7

What conditions are erythema nodosum associated with?

Answer 7

The most common causes are:

• streptococcal infection
• sarcoidosis
• inflammatory bowel disease
• drugs (penicillins, sulphonamides, oral contraceptive pill)

Question 8

What is pretibial myoedema?

Answer 8

• Pretibial myxoedema is a form of diffuse mucinosis in which there is an accumulation of excess glycosaminoglycans in the dermis and subcutis of the skin.
• symmetrical, erythematous lesions seen in Graves’ disease
• shiny, orange peel skin

Question 9

What is pyoderma gangrenosum?

Answer 9

• Pyoderma gangrenosum is an autoinflammatory disease due to some form of neutrophil dysfunction.
• Initially small red papule → later deep, red, necrotic ulcers with a violaceous border

Question 10

What is pyoderma gangrenosum associated with?

Answer 10

• Idiopathic in 50% of cases

* May also be seen in inflammatory bowel disease, connective tissue disorders and myeloproliferative disorders

Question 11

What is Necrobiosis lipoidica diabeticorum?

Answer 11

• shiny, painless areas of yellow/red skin typically on the shin of diabetics
• often associated with telangiectasia

Question 12

What is vitiligo?

Answer 12

• Vitiligo is an autoimmune condition which results in the loss of melanocytes and consequent depigmentation of the skin.
• It is thought to affect around 1% of the population and symptoms typically develop by the age of 20-30 years.

Question 13

What conditions are associated with vitiligo?

Answer 13

• type 1 diabetes mellitus
• Addison’s disease
• autoimmune thyroid disorders
• pernicious anaemia
• alopecia areata

Question 14

What is losing localised, well demarcated patches of hair called? there could be small broken “question mark” hairs around the edge.

Answer 14

Alopecia areata

hair will regrow in 50% - 1yr, 85-90% evenually

Question 15

What is alopecia areata?

Answer 15

an autoimmune disease

Question 16

What are the triggers for alopecia areata?

Answer 16

• Viral infection
• Trauma
• Hormonal change
• Emotional/physical stressors

Question 17

What is impetigo?

Answer 17

Impetigo is a superficial bacterial skin infection usually caused by either:

• Staphylcoccus aureus
• Streptococcus pyogenes.

Question 18

How do you treat localised impetigo?

Answer 18

topical fusic acid

Question 19

how do you treat widespread impetigo?

Answer 19

flucloxacillin → macrolide in pen. allergy

Question 20

What is the treatment for mild/moderate and severe Acne Rosacea?

Answer 20

• mild/moderate: topical metronidazole

* severe/resistant: oral tetracycline

Question 21

What is melasma?

Answer 21

• Melasma is a chronic skin disorder that results in symmetrical, blotchy, brownish facial pigmentation
• It is a condition associated with the development of hyperpigmented macules in sun-exposed areas, particularly the face.
• The term chloasma is sometimes used interchangeably but more specifically describes the appearance of melasma during pregnancy
• It is associated with pregnancy, combined oral contraceptive pill, hormone replacement therapy

Question 22

What is the management of vitiligo?

Answer 22

• Sun block for affected areas of skin
• Camouflage make-up
• Topical corticosteroids may reverse the changes if applied early
• There may also be a role for topical tacrolimus and phototherapy, although caution needs to be exercised with light-skinned patients

Question 23

What disorder of the GI tract is dermatitis herpetiformis associated with?

Answer 23

Coeliacs disease

Question 24

Teenager with a history of asthma and eczema presents with a rash on the face and torso that is covered in yellow crusts. he feels generally unwell. what is this?

Answer 24

• Eczema herpeticum → Dermatalogical emergency
• Most cases are caused by Herpes simplex virus type 1 or 2
• Treat with oral aciclovir

Question 25

Which fungi causes dandruff, seborrhoeic dermatitis and Pityriasis versicolor?

Answer 25

Malassezia furfur

Question 26

What is Erythroderma?

Answer 26

Erythroderma is a term used when more than 95% of the skin is involved in a rash of any kind

Question 27

What are the main causes of erythroderma?

Answer 27

• Eczema
• Psoriasis
• Drugs e.g. gold
• Lymphoma, leukaemia
• Idiopathic

Question 28

What is the term for a net like rash?

Answer 28

Livedo reticularis