Dermatology Flashcards
what is a papule
small lump <5mm
what is a nodule
larger lump 5-10mm
what is a vesicle
small water blister
what is a bulla
larger water blister
what is a pustule
pus-filled vesicle
what is erythema
redness
what is a macule
non palpable area of discoloration
what is a patch
macule >2cm
what is a plaque
plapable, flat topped area >2cm
what are excoriations
scratches
what is striae
stretch marks
what is pruritus
itching
what is atrophy
thinning
what is telangiectasia
thread vein
what is ichthyosis
scaling
what is erosion
loss of epidermis (superficial)
what is an ulcer
loss of epidermis and dermis (deep)
what is lichenification
thickening of the skin with exaggerated skin markings
what is hirsutism
too much hair
what is alopecia
too little/no/thinning hair
what does the process of inflammation result from
- vasodilation
- increased microvascular permeability resulting in protein rich exudate
- influx ok leukocytes
clinical signs of skin inflammation
- rubor (redness)
- tumor (growth/swelling)
- calor (radiates heat)
- dolor (pain)
- functio laesa (loss of function)
what is psoriasis
- autoimmune disease, may be inherited
- causes red, flaky, crusty patches of skin covered with silver-coloured scales
- patches normally appear on elbows, knees, scalp and lower back but can be anywhere
- most have small patches but can be itchy or sore
how is psoriasis caused
when skin cells are replaced more quickly than usual
- normally, skin cells arise from stem cells at parabasal level and as cells mature they gradually move up layers of epidermis until they die and flake off at outermost layer which takes 3-4 weeks
- in psoriasis the process takes 3-7 days so immature cells accumulate and outer layer of keratin is lost causing crusty red patches with silvery scales - reduced epidermal transit time
- due to problems with immune system where T cells attack the dividing cells
common psoriasis triggers
- injury to skin like cut, scrape, insect bite, sunburn
- drinking excessive amounts of alcohol
- smoking
- stress
- hormonal changes particularly puberty and menopause
- certain medicines like lithium, anitmalarials, anti-inflammatories, ACE inhibitors
- other immune disorders like HIV
treatments for psoriasis
topical
- emollients
- salicylic acid
- topical steroids
- vitamin D analogues
systemic
- psoralen and PUVA
- cytotoxic drugs
- retinoids
- monoclonal antibodies
psychosocial impacts of psoriasis
- poor self-esteem
- treated like it’s contagious
what is eczema (atopic dermatitis)
- chronic skin condition that makes skin red, dry, itchy and cracked
- appear as small or large patches on any area of the body but usually starts on face in infants and in skin creases
- main symptoms are dry, itchy skin and rash and severe cases may show signs of inflammation, cracking and bleeding and can be extremely painful
psychosocial impacts of eczema
- patients want to scratch constantly even in sleep (children with eczema and parents can lose up to 2 hours of sleep a night)
- frustrating, painful, annoying
- not contagious but may be treated like it is
- children with allergic eczema have worse quality of life than children with asthma, diabetes or epilepsy
- may miss school, skip activities, feel social isolation
how is eczema caused
internal - allergic to other things
- asthma, hayfever and eczema
- food allergies eg. milk, egg, peanut, wheat, soy, shrimp, fish
external
- occupation related
- soap, detergents
- stress
treatments for eczema
topical
- emollients
- topical steroids
- topical immunosuppressants
systemic
- anti-histamines
- immunosuppressants
what is malignant melanoma
- skin cancer that can spread to other organs in the body - fifth most common cancer in the UK
- most common sign is a new mole or change in an existing mole
- can occur anywhere in the body but uncommon in areas protected from sun exposure like scalp and bum
- melanomas usually have irregular shape and more than one colour and mole may be itchy or bleed
two types of malignant melanomas
nodular melanomas
- changing lump on the skin that’s black to red in colour
- grow on previously normal skin
- common on head, neck, chest and back
- bleeding or oozing common
- faster developing that can quickly grow downwards into deeper layers
lentigo maligna melanomas ~10%
- initially flat and develop sideways in surface layers
- look like a freckle but usually larger, darker and stand out
- gradually get bigger and change shape
- may grow downwards into deeper layers and can from nodules
- commonly affect older people who spend lot of time outdoors
- develop slowly over a number of years in areas exposed to sun
how is melanoma caused
- skin cells that begin to develop abnormally
- sudden intense exposure to UV light from sun causing sunburn (problematic for those with lots of moles or freckles, pale skin, red or blonde hair)
- genetic predispositions due to mutation in CDKN2A gene
- non-inherited mutations eg. BRAF gene
treatments for malignant melanoma
- wide local excision
- radiotherapy
- chemotherapy
what is vitiligo
- long-term condition where pale white patches develop on the skin which is caused by the lack of pigment (melanin) in the skin
- can affect any area but most common on face, neck, hands and skin creases
- can develop where there are hair roots, turning hair white or grey
- starts as a pale patch of skin that gradually turns completely white
- edges of the patch may be smooth or irregular and sometimes red or inflamed or show signs of hyperpigmentation
- rarely causes skin discomfort but may be itchy
- patches usually permanent
areas of the body most commonly affected by vitiligo
- skin around mouth and eyes
- fingers and wrists
- armpits
- groin
- genitals
- inside of mouth
types of vitiligo
non-segmental vitiligo (bilateral/generalised)
- symptoms appear on both sides of the body as symmetrical white patches
- most common type ~9/10
- patches appear on backs of hands, arms, skin around body openings, knees, elbows, feet
segmental vitiligo (unilateral/localised)
- white patches only affect one area of the body
- more common in children as it starts earlier ~3/10 children
universal vitiligo
- very rare
- vitiligo affects whole body
how is non-segmental vitiligo caused
- autoimmune condition where T cells attack healthy melanocytes and kill them
increased risk if
- other members of family have it
- family history of other autoimmune conditions
- presence of another autoimmune condition
- presence of melanoma or cutaneous T-cell lymphoma
how is segmental vitiligo caused
- neurochemicals released from nerve endings in skin which cause increase in ROS causing melanocytes to destroy themselves
- triggered by stress, skin damage or work-related exposure to dermatalogical toxins
treatments for vitiligo
- topical steroids
- calcineurin inhibitors
- cosmetic camouflage
- sunscreen
what is alopecia areata
- when hair is lost from some or all areas of the body, mostly on the scalp
- can lose all the hair on scalp (alopecia totalis) or all body hair (alopecia universalis)
how is alopecia areata caused
- systemic autoimmune disorder where body attacks its hair follicles and suppresses hair growth
- may be inherited
- shares genetic risk factors with other autoimmune diseases like rheumatoid arthritis, type 1 diabetes and coeliac disease
treatments for alopecia areata
- topical and intralesional steroids
- calcineurin inhibitors
- cosmetic methods
what is acne
skin condition that affects the sebaceous glands
symptoms of acne
- comedones (blackheads and whiteheads)
- papules
- pustules
- nodules
- cysts
- scars
how is acne caused
depends on the type of acne
treatments for acne
- topical agents
- topical and oral
- surgical/intralesional injections
- more potent oral treatments
