Derm

Question 1

2 commonest disease assoc with SJS

Answer 1

Preceding herpes simplex or Mycoplasma pneumoniae infections

Question 2

How many cutaneous strawberry naevi should raise suspicion for internal lesions?

Answer 2

6 or more - need further investigation

AKA haemangioma

Question 3

What is tinea incognito

Answer 3

Fungal skin infection in which the appearance has been altered by inappropriate tx with steroids

Question 4

A very firm, white or violaceous patch of skin. As it develops it will have a well demarcated red/violaceous edge

Answer 4

Morphoea

As the lesions develops the edge will become the same colour as the center of the lesion, it will become very firm with an atrophic glazed surface appearance

Question 5

Scabies can present with a rash on the body that is similar to eczema but should also have involvement of palms, soles and/or genitals T/F

Answer 5

T

Question 6

Isotretinoin can cause hirsutism T/F

Answer 6

F side effect can be diffuse alopecia areata

Question 7

What labs need to be monitored for a pt on isotretinoin

Answer 7

Serum lipids and LFTs - prior to tx, 4 weeks and maybe also 8 weeks

Question 8

Pregnancy needs to be avoided in a pt on isotretinoin and for 6 months after tx T/F

Answer 8

For up to one month after tx

Question 9

Haemangiomas are more common in what race and sex

Answer 9

White
Females x3 more common than males
Also more common in preterm infants

Question 10

% resolution of haemangiomas by age

Answer 10

50% 5 yrs
70% 7 yrs
90% 9 yrs

Question 11

Indications for tx of haemangiomas?

Answer 11

1. Psychological distress
2. Impinging on vital structures - vision, airway
3. Ulcerated and bleeding
4. Secondary infection

Question 12

Steroids can be used in the tx of haemangiomas T/F

Answer 12

True - systemic or intralesional

Also beta blocker; subcut interferon gamma, laser or excision

Question 13

The majority of haemangiomas are present at birth T/F

Answer 13

F - only 30% are present at birth

Question 14

About half of haemangiomas leave some form of permanent skin change T/F

Answer 14

T - eg telangiectasiae, superficial dilated veins, epidermal atrophy

Question 15

Port wine stain on a limb with associated soft tissue and bony over overgrowth. Can also have venous malformations. Syndrome?

Answer 15

Klippel-Trenauay syndrome

Question 16

Tuberous sclerosis is associated with what skin abnormality?

Answer 16

Hamartomas
Shagreen patches 
Ash leaf macules
Perungual fibromata
Facial angiofibromata

Question 17

Features of pompholyx

Answer 17

Rare in children less than 10 yrs old
Sudden onset of crops of clear vesicles, usually bilateral involving fingers, toes, palms and soles. Often recurrent
Often hx of atopy

Question 18

When is typical age of onset of epidermolysis bullosa simplex

Answer 18

Onset in early childhood, around the time child starts to walk

EB simplex is localised to fiction sites, usually hands and feet

Question 19

When and where does chronic bullous disease of childhood usually present?

Answer 19

Usually > 3 yrs old (note older than EB simplex)
Lesions typically affect the peri anal area and spread to the trunk, thighs, limbs, hands and feet. There may also be mucosal involvement (mouth, genitals, eyes and nose)

AKA linear immunoglobulin A disease

Question 20

What is the mechanism of action of UBV phototherapy for psoriasis

Answer 20

Induction of pyrimidine dimerisation

Note: disease is due to increased cell turn over

Question 21

Classification of acne?

Answer 21

Mild: <20 comedones and < 15 inflammatory lesions (or less than 30 lesions total)
Mod: 20-100 comedones and 15 -50 inflammatory lesions (or 30-125 lesions total)
Severe” > 100 comedones, >50 inflammatory lesions and > 5 pseudocysts (or > 125 lesions total)

Question 22

Where is dermatitis herpetiform classically?

Answer 22

Symmetrically distribution
On the extensor surfaces ( elbows, knees, neck) and back

Note: it is very itchy and comes and goes

Question 23

Describe the hair loss and scalp findings in alopecia areata?

Answer 23

Hair loss is well circumscribed
Scalp is normal

Note: also can be assoc with nail changes.
In tinea capitis there is variable amount of erythema and scaling of the scalp

Question 24

Presentation of telogen effluvium?

Answer 24

Sudden increase in hair shedding, diffusely, 3-4 months after an inciting event such as an illness or medication

Other causes of diffuse hair loss are hypothyroidism and Zn deficiency

Question 25

Most common cause of acute urticaria in children?

Answer 25

Viral trigger

Question 26

Keratoderma blenorrhagica is highly diagnostic of what disease?

Answer 26

Reactive arthritis

Note: they are brown aseptic abscesses on soles and palms

Question 27

What is the typical distribution of chronic bullous disease of childhood?

Answer 27

Typically affects the perianal area and spread to the trunk, thighs, limbs, hands and feet

Note: they are small tense blisters on an erythematous background

Question 28

What is the difference between SJS and TEN?

Answer 28

The amount of skin involved
SJS <10%
TEN > 30%

Between 10 - 30% is SJS/TEN overlap

Note: erythema multiforme is when there is no mucosal involvement

Question 29

Differentiate vitaligo from piebaldism distribution?

Answer 29

Hands and feet are spared in piebaldism

Question 30

Gradually progressive red plaque, annular in shape with crusting and induration at the periphery and scaring at the centre. Tinea corporis vs Lupus vulgaris

Answer 30

Lupus vulgaris - most common manifestation of cutaneous TB. Starts as a painless reddish- brown nodules and then progresses to an irregular red plaque and can ulcerate if not treated

Note: tine corporis has a central clearing