Derm Flashcards
2 commonest disease assoc with SJS
Preceding herpes simplex or Mycoplasma pneumoniae infections
How many cutaneous strawberry naevi should raise suspicion for internal lesions?
6 or more - need further investigation
AKA haemangioma
What is tinea incognito
Fungal skin infection in which the appearance has been altered by inappropriate tx with steroids
A very firm, white or violaceous patch of skin. As it develops it will have a well demarcated red/violaceous edge
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
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
T
Isotretinoin can cause hirsutism T/F
F side effect can be diffuse alopecia areata
What labs need to be monitored for a pt on isotretinoin
Serum lipids and LFTs - prior to tx, 4 weeks and maybe also 8 weeks
Pregnancy needs to be avoided in a pt on isotretinoin and for 6 months after tx T/F
F - For up to one month after tx
Haemangiomas are more common in what race and sex
White
Females x3 more common than males
Also more common in preterm infants
% resolution of haemangiomas by age
50% 5 yrs
70% 7 yrs
90% 9 yrs
Indications for tx of haemangiomas?
- Psychological distress
- Impinging on vital structures - vision, airway
- Ulcerated and bleeding
- Secondary infection
Steroids can be used in the tx of haemangiomas T/F
True - systemic or intralesional
Also beta blocker; subcut interferon gamma, laser or excision
The majority of haemangiomas are present at birth T/F
F - only 30% are present at birth
About half of haemangiomas leave some form of permanent skin change T/F
T - eg telangiectasiae, superficial dilated veins, epidermal atrophy
Port wine stain on a limb with associated soft tissue and bony over overgrowth. Can also have venous malformations. Syndrome?
Klippel-Trenauay syndrome
Tuberous sclerosis is associated with what skin abnormality?
Hamartomas Shagreen patches Ash leaf macules Perungual fibromata Facial angiofibromata
Features of pompholyx
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
When is typical age of onset of epidermolysis bullosa simplex
Onset in early childhood, around the time child starts to walk
EB simplex is localised to fiction sites, usually hands and feet
When and where does chronic bullous disease of childhood usually present?
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
What is the mechanism of action of UBV phototherapy for psoriasis
Induction of pyrimidine dimerisation
Note: disease is due to increased cell turn over
Classification of acne?
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)
Where is dermatitis herpetiform classically?
Symmetrically distributed
On the extensor surfaces ( elbows, knees, neck) and back
Note: it is very itchy and comes and goes
Describe the hair loss and scalp findings in alopecia areata?
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
Presentation of telogen effluvium?
Sudden increase in hair shedding, diffusely, 3-4 months after an inciting event such as an illness, pregnancy, loss of loved one or medication.
Note: tx is reassurance only
Other causes of diffuse hair loss are hypothyroidism and Zn deficiency
