Dermatology Flashcards
Atopic conditions associated with skin conditions
Eczema
Asthma
Hay fever
Urticaria
Which cardiac medication can cause psoriasis
Beta blocker
What skin condition can antibiotics cause
Rash
Why is social history more important in skin conditions
Job - hand/skin/chemical exposure
Pets
Foreign travel
Sun exposure (real or artificial)
What to clarify when asking about sun exposure
Real or artificial, do u use sun screen?
Describe the type 1 - 6 skins on the fitzpatrick scale
Type 1 - ginger, white burns easily
Type 6 - black, never burns
Everything else in between, 4-5 is asian, arabic.
What is key in the history of a skin lesion to differentiate something sinister from something benign
How quickly it has changed, did it get bigger quickly over a few weeks, months, years or always been the same.
How should the patient be dressed in a dermatology examination
Full undressed
How to describe a lesion? - SCAM
Size
Color
Associated secondary change
Morphology, margin
When do u use the ABCDE system to describe something on the skin?
When it is pigmented (moles)
What is the ABCDE system used to describe a skin lesion
Asymmetry? Border Color variation Diameter (Size) Elevation & evolution
What to notice in palpation of a skin lesion
Surface texture
Consistency (what its filled with)
Mobility
Temperature
What is a macule
Flat discoloration (cannot feel if eyes closed)
Small
What is a large macule called
Patch
What is a large discoloration that cannot be felt
Patch
What is a small solid raised lesion
Papule
What is a nodule
Large solid raised lesion
What is a pus filled lesion called
Pustule
What is another name for a blister
Bullous
What is a small blister called
Vesicle
What is a plaque
Elevated scaly lesion
Describe a target lesion
Like a bullseye, concentric circles with two shades of color
What is koebnerisation
Hardening of the lesion caused by trauma or scratching
What is the definition of erythroderma
Erythematous skin >90% of body
Why is erythroderma an emergency
Failure of skin
Failure of infection barrier
Failure to keep moisture in
Failure to regulate body temperature (hypothermia)
What is a type of generalised vesicle that can develop all over the body and is an emergency
Eczema hepaticum
What skin condition can cause blindness
Eczema herpaticum
What is PPPP and describe it
Palmar plantar pustular psoriasis
Purulent sterile pustules that develop on the sole of the feet.
PPPP pustules are caused by infection - T or F
F, they are just filled with neutrophils
What are the risk factors of skin cancer
Sun exposure
Age
Family link
Other skin cancers
Describe a seborrhoeic kerastosis
Stucked on appearance Cribiform Craggy Light or dark Rough texture
What pre-malignant skin lesions can lead to skin cancer
Actinic keratoses
Bowen’s disease
Cutaneous horn
What can precede a malignant melanoma
Lentigo maligna
Difference in appearance of an actinic keratoses and Bowen’s disease
BD is more organised, progressed dysplasia of the epidermis
Compared to AK which is more diffused, red and can be rough
What does a cutaneous horn look like
A vertically growing structure that can have deeper roots in the skin
Appearance of a basal cell carcinoma
Pearly transluence
Rolled edge
Can be ulcerated in the middle
Arborising telangectasia
Characteristics of a BCC
Slow growing
Sun exposed site
Not tender
Which types of skin cancer require 2 week notice referral
SCC and malignant melanoma
Why is SCC more dangerous than BCC
Can metastasise, more aggressive, faster growing
How to differentiate a benign naevi from a malignant melanoma
Growing bigger rapidly Lack of symmetry Bleeding Painful Change in color
Why is an elevated malignant melanoma more worrisome?
Means it is growing deeper into the skin
What is a malignant melanoma under the nail called and how to differentiate that from a bruise
Acral lentiginous
Will be on the skin as well which a simple nail bruise will not
What is it called when a malignant melanoma is not black
Amelanotic melanoma
Difference between irritant dermatitis and allergic dermatitis
Irritant dermatitis caused by direct skin damage
Allergic is a substance which has been sensitised by the body to cause a reaction, takes 1-2 days.
typical causes of allergic dermatitis?
latex, nickel, hennah, elastoplast, hair dye, fragrances
what occupations are risk factors for allergic dermatitis
hair stylist, cleaners, health care workers
symptoms of atopic dermatitis
tend to be on flexors
dry, scaly patches
itches, can see lichenification due to scratching
typical sites for seborrhoeic dermatitis
medial eye brows
scalp
around nose
upper chest
characteristics of discoid dermatitis
round shaped eczema commonly on leg
how do varicose eczema form
venous insufficiency due to poor blood flow
can lead to ulceration
what can stasis eczema turn into
ulceration
signs and symptoms of eczema herpeticum
wide spread ulcers/vesicles
painful, rapid spread
can cause blindness
systemically unwell
difference between eczema and psoriasis
eczema normally ill defined borders, more diffuse patches
psoriasis tend to be plaques, with thick surfaces
eczema is red and itchy, scratched often
psoriasis is less itchy, whitish and slivery
2 age peaks of psoriasis
late teens and after middle age
describe the koebner phenomenon
trauma to an area brought on by scratching, leads to hardening and keratising of the surface, leading to psoriasis
what is a psoriatic plaque made of
keratinocytes and keratin
where are psoriatic plaques commonly found
extensor surfaces - eblow, back of hands, knees, nape of neck, lumbar region
what is a psoriatic plaque that forms on the inner elbow called
flexural psoriasis
describe guttate psoriasis
small tear drop papules that form all over, usually around the trunk, upper arm and thighs. usually follows strep pharyngitis
describe nail changes in psoriasis
pitting
subungal onycholysis
subungal hyperkeratosis
what is onycholysis
painless separation of the nail from nail bed
what is erythrodermic psoriasis
wide spread generalised redness of the skin, can be fatal. due to dehydration and hypothermia
conditions associated with psoriasis
psoriatic arthritis IBD uveitis coeliacs disease metabolic syndrome
what are metabolic syndromes associated with psoriasis
t2dm obesity h/t h/c gout cvd
when is a common age for eczema presentation?
<5 y/o
if a skin lesion is not itchy, can it still be atopic eczema?
unlikely
difference between allergic contact dermatitis and irritant contact dermatitis
ACD - type 4 HS, delayed response, prior sensitisation, can be on areas not exposed to allergen
ICD - non-HS reaction, direction irritation of skin by substance, causing inflammation on exposed skin, comes within 48 hours. associated with atopy
common causes of irritant contact dermatitis?
soaps
detergent
hair dyes
paints and oils
what organism is associated with seborrhoeic dermatitis?
mellasezia
describe discoid dermatitis
round erythematous lesions with raised edges, usually symmetrical, can become plaques. itchy.
what to exclude when suspecting discoid dermatitis
tinea
what causes pigmentation of varcose dermatitis?
haemosiderin deposits
symptoms of varicose eczema
itching, pain, swelling, redness, usually dry, pigmented - dark brown
common area for varicose eczema
around ankles and up the calf
when is patch testing done?
to find the cause of allergic contact dermatitis
how long is the patch left on for in patch testing?
48 hours
when is skin prick testing done?
to find the cause of an allergy
features of erythema nodosum
red, tender nodules, poorly defined borders, 2-6cm diameter. nodules first appear tense, hard and painful before coming fluctuant.
prodrome of erythema nodosum
fever, aching and joint pains
common area for erythema nodosum
front of legs, shins
arthralgia is uncommon in erythema nodosum - T or F
F, it is common, usually red, swollen, tender with morning stiffness.
common cause of erythema nodosum
underlying infection
what skin condition can be associated with gastroenteritis
erythema nodosum
what bacterial infection is most common underlying cause of erythema nodosum?
streptococcal
management for erythema nodosum
self-limiting, supportive
a 38 year old woman presents with itchy, erythematous lesions on her hands and feet. they are red and round with a pale center. she reports having recently recovered from pneumonia. what is the diagnosis of the skin lesions?
erythema multiforme
what skin condition is classically described as a target lesion
erythema multiforme
