INTRODUCTION TO CLINICAL DERMATOLOGY Flashcards
What is a naevus?
A localised malformation of tissue structures formed by a cluster of melanin, also known as a moles
what does pruritus mean?
itching
what is erythema?
redness which blanches on pressure caused by inflammation and vasodilatation
what are macules?
A circumscribed, flat area of discolouration that is less than 10 mm in diameter e.g. a freckle
what are papules?
A solid, elevated lesion with no visible fluid which may be up to 0.5cm in diameter
what are pastules?
raised red lesions containing white/yellow pus (neutrophils)
what are petechiae?
a small red or purple spot caused by bleeding into the skin
what are ecchymoses?
A discolouration of the skin resulting from bleeding underneath, typically caused by bruising
what is hyper-pigmentation?
darker areas in the skin because of increased melanin
what is de-pigmentation?
white patches of skin due to absence of melanin
what is seborrhoea?
excessive discharge of sebum from sebaceous glands
what are open comedones?
blackheads
why do open comedones appear black?
because the enlarged hair follicle opening is filled with melanin
what are closed comedones?
white heads
what are nodules?
deep, inflamed solid lesions typically over 0.5cm in diameter that are frequently tender and painful
what are cysts?
a papule or nodule that contains fluid
what is lichenification?
when the skin thickens and becomes leathery
what is a bulla?
a large fluid-filled blister greater than 0.5cm
what are vesicles?
circumscribed epidermal elevations in the skin containing clear fluid and less than 0.5cm in diameter
what is a plaque?
an elevated area of skin of 2cm or more in diameter
what is the Koebner phenomenon?
The formation of skin lesions on parts of the body where a person doesn’t typically experience lesions
what is an abscess?
a localised accumulation of pus, similar to a pimple but larger and deeper under the skin
what is telangiectasia?
dilated or broken blood vessels located near the surface of the skin/mucous membrane. Often appears as fine red or pink lines which temporarily whiten when pressed
what is Breslow’s depth?
measuring, using an ocular micrometer, from the granular layer of the epidermis to the deepest point of invasion
what is dermatology?
a branch of medicine that deals with skin and diseases of the skin (including fat, hair, nails, oral and genital mucous membranes)
when inspecting a skin condition what should you look for in the general observation?
SCAM Size shape Colour Associated secondary changes Morpolgy and margins
if the lesion is pigmented what should you look for?
ABCD Asymmetry Border irregularity Colours (2 or more) Diameter (>6mm?)
what does ‘generalised’ mean?
all over the body
what does ‘localised’ mean?
restricted to one area of the skin only
what does ‘flexural’ mean?
within flexures e.g. behind ears or in folds of neck
What is a PASI score?
Psoriasis Area and Severity Index
what does the PASI score measure?
intensity
erythema
induration
desquamation
what are woods lamps?
a light that uses long wave ultraviolet light for examining pigmentary changes and fluorescent infections
what are dermascopes used to see?
pigmented lesions
what are 3 examples of inflammatory dermatosis?
acne
atopic eczema
psoriasis
how prevalent is acne?
85% of people between 12-25 years old
what are the clinical features of acne?
seborrhoea, non-inflammatory lesions including open and closed comedones, inflammatory lesions including papules and pastules, nodules, scarring of various severity
what does the presence of mid-facial comedones early on indicate?
the person is more likely to experience severe acne
what are atrophic acne scars?
an indented scar that heals below the normal layer of skin tissue when tissue is unable to regenerate
what are hypertrophic acne scars?
firm, raised scars that grow above the surface of the skin.
when does atopic eczema develop?
in childhood
why is atopic eczema a chronic condition?
because it relapses and remits after environmental triggers
how does atopic eczema present?
itchy, erythematous dry scaly patches
in babies common on face and extensor aspects of limbs
As you grow up, more common on flexor aspects of limbs
what is pompholyx eczema?
a type of eczema that causes tiny blisters to develop across the fingers, palms of the hands and sometimes the soles of the feet.
what causes pompholyx eczema?
fungal infections
stress
sweating
reaction to something you touched
what causes psoriasis?
hyper-proliferation of keratinocytes
what’s the most common type of psoriasis?
plaque psoriasis
how does plaque psoriasis present?
dry, red skin lesions (plaques) covered with silvery scales.
what is erythroderma?
a severe and potentially life-threatening inflammation of most of the body’s skin surface
what can cause erythroderma?
exacerbation of an underlying skin disease e.g. eczema, psoriasis
what’s the physiology of skin infections?
when there is skin damage, the normal skin microflora penetrate and result in infection
what are some common bacterial skin infections?
cellulitis, erysipelas, impetigo, folliculitis, and furuncles and carbuncles
what are some common viral skin infections?
chickenpox shingles warts measles hand, foot and mouth disease
what are some common fungal skin infections?
athletes foot
jock itch
ringworm
what are seborrheic keratoses?
a noncancerous (benign) growth on the skin. It’s color can range from white, tan, brown, or black. Most are raised and appear “stuck on” to the skin.
what are the 4 main types of skin cancer?
basal cell carcinoma
squamous cell carcinoma
Merkel cell cancer
melanoma
what is the most preventable risk factor for skin cancer?
sun exposure
what are the properties of basal cell skin cancer?
- slow growing
- locally invasive
- malignant tumours of epidermal keratinocytes
what are some risk factors of basal cell skin cancer?
UV exposure history of frequent or severe sunburn having skin type 1 increasing age male sex immunosuppression previous history of skin cancer genetic predisposition
how does basal cell cancer present?
nodular, superficial, cystic, morhoeic, sclerosis, keratotic or pigmented
what is nodular basal cell carcinoma?
Small, skin-coloured papule or nodule with surface telangiectasia and a pearly rolled edge, the lesion may have a necrotic or ulcerated centre
what is the most common form of skin cancer?
basal cell skin cancer
what’s the second most common form of skin cancer?
squamous cell skin cancer
how is squamous cell skin cancer characterised?
abnormal accelerated growth of squamous cells
scaly, red patches, open sores, wart like skin, raised growths with central depressions…
what causes squamous cell skin cancer?
exposure to UV radiation
what is malignant melanoma?
a neoplasm of melanocytes or a neoplasm of the cells that develop from melanocytes.
what are the risk factors for malignant melanoma?
excessive UV exposure
skin type 1
history of multiple or atypical moles
family history/previous history of melanoma
what are the types of malignant melanoma?
superficial spreading melanoma
nodular melanoma
lentigo maligna melanoma
acral lentiginous melanoma
outline the Fitzpatrick scale?
Skin type 1 = always burns, never tans, palest, freckles
Skin type 2 = usually burns, tans minimally, light coloured
Skin type 3 = sometimes mildly burns, tans uniformly in a golden colour
Skin type 4 = burns minimally, tans well, moderate brown
Skin type 5 = rarely burns, tans very easily, dark brown
Skin type 6 = never burns, deeply pigmented
what are some dermatological manifestations of liver disease?
pruritus
spider nave
palmar erythema
white nails
what are some dermatological manifestations of diabetes mellitus?
gangrene, neuropathic ulcers, necrobiosis lipoidica, granuloma annulare
what are some dermatological manifestations of inflammatory bowel disease?
erythema nodosum
pyoderma gangrenosum
anal fissures
