part 1 Flashcards
what are the layers of the skin?
(stratum corneum)
epidermis
dermis
subcutaneous tissue
what is the role of the stratum corneum?
varies in thickness, more in the hands = more protective. Sheds in normal skin to give the skin a healthy appearance.
what is the role of the epidermis?
an infective barrier
what is the cause of psoriasis?
hyperproliferation of the epidermis
what is atopy?
Atopy refers to the genetic tendency to develop allergic diseases such as allergic rhinitis, asthma and atopic dermatitis (eczema).
the tendency to produce an exaggerated IgE immune response to otherwise harmless environmental substances
why should you examine the joints of a psoriasis patient?
may have arthritic psoriasis
what is the difference between a papule and a nodule?
papule = small lump (<5mm)
nodule = larger lump (>5mm|)
what is the difference between a vesicle and a bulla?
vesicle = small water blister
bulla = large water blister
define
- alopecia
- hirsutism
- excoriations
- telangiecta
alopecia = hair loss hirsutism = hairiness
excoriations = scratch marks
telangiecta = thread vein
what are striae?
stretch marks
define
- pruritus
- atrophy
pruritus = itching
atrophy = thinning
define the term
- macule
- patch
- plaque
macule = non palpable area of discolouration
patch = macule >2cm
plaque = palpable, flat topped area >1-2cm
what is an ulcer?
superficial loss of epidermis
what is Lichenification?
loss of epidermis (superficial)
loss of epidermis and dermis (deep)
thickening of the skin with exaggerated skin marking
what is contact dermatitis?
Contact dermatitis is an allergic or irritant skin reaction caused by an external agent.
what are the types of contact dermatitis?
2 types of contact dermatitis,
irritant contact dermatitis is caused by direct toxicity and can occur in any person without prior sensitisation.
Allergic contact dermatitis is a delayed hypersensitivity reaction, which requires prior sensitisation.
what is the pathophysiology of allergic contact dermatitis?
Allergic contact dermatitis is a type 4 or delayedhypersensitivityreaction and occurs 48–72 hours after exposure to theallergen. The mechanism involves CD4+ T-lymphocytes, which recognise anantigenon the skin surface, releasingcytokinesthat activate the immune system and cause the dermatitis
what are the symptoms of allergic contact dermatitis?
Results in localised burning, stinging, itching, blistering, redness, and swelling at the area of contact with the allergen or irritant.
what can predispose people to contact dermatitis?
a history of atopy
how is irritant contact dermatitis treated?
irritant = moisturisers or topical corticosteroids and irritant avoidance
allergic (mid-moderate) = topical corticosteroids + allergen avoidance. can also try topical calcinurin inhibitors
of severe, topical corticosteroids, if this doesn’t work, oral corticosteroids.
what is patch testing?
if cant treat allergic dermatitis in primary care, can refer to dermatology to do patch testing for the allergen to avoid it
what are the features of a basal cell carcinoma and how is it diagnosed?
ulcer raised rolled edge
prominent fine blood vessels around lesions
nodule on skin
can usually diagnose visually but confirm with excision biopsy
who usually gets basal cell carcinomas?
occur in middle age and elderly, usually on face
how are basal cell carcinoma’s managed?
complete excision is ideal
can use radiotherapy if surgery isn’t appropriate
refer routinely, if low risk can manage in a community skin cancer clinic
high risk features, refer to dermatology
what is psoriasis?
chronic inflammatory condition
presents as erythematous, circumscribed scaly papules and plaques
may be associated with arthritis (psoriatic arthritis)
can be classified as
- plaque psoriasis
- guttate
- erythrodermic
- pustular
how is psoriasis treated?
lifestyle e.g smoking, drinking, reduce stress
treatment
- mild = topical corticosteroid and/or topical vitamin D analogue, applied at different times, until the skin is clear
what are the features of a squamous cell carcinoma?
dry
scaly
bleeds easily
worse than basal cell carcinoma
