Introduction To Clinial Dermatology Flashcards
Information that should be routinely obtained from a dermatological history
- nature, site and duration of problem
- how it has changed over time
- symptoms associated with it
- aggravating and relieving factors
- previous and current treatments
- recent contact, stressors, illness or travel
- history of sunburn and use of tanning beds
Also ask about occupation, hobbies or any animal contact
How are lesions described
SCAM
S size and shape
Colour
Associated secondary changes
Morphology and margin (borders)
And if lesion is pigmented use ABCDE
Asymmetry
Irregular BORDER
Two or more COLOURS within the lesion
Diameter >6mm
Evolution
What is a lesion
An altered area on the skin
Definition of naevus
A localised malformation of tissue structures. A benign growth on skin formed by a cluster of melanocytes.( mole = naevus)
Definition of pruritus
Itching
Definition of erythema
Redness which blanches on pressure
(Due to inflammation and vasodilation
Examples of vascular lesions
Petechiae = small <3mm macules that don’t blanch
Purpura = red/purple due to bleeding into skin (don’t blanch on pressure)
Ecchymosis = larger bruise like patches
Characteristics of acne and clinical features
Chronic inflammatory disease of pilosebaceous unit
Prevalence 650 million in world
Normally as a result of seborrhoea (excessive oiliness of skin) bacteria attracted to it and inflammation occurs
Non-inflammatory lesions such as open and close comedones
Inflammatory lesions = papules and pustules
Scarring
Open vs closed comedone
Open comedone/ blackhead = enlarged hair follicle filled with melanin
Closed comedone/ whitehead = small raised non-inflamed spot
What is a papule
Superficial red inflamed spot without pus
- is palpable and is distinguished from macule which is flat and not raised
What is a pustule
Raised red lesions that may be white or yellow and contains pus
Filled with neutrophils
Definition of a nodule
Solid lesions that are typically larger and arise deeper within the dermis or subcutis
Tender and painful
Definition of a cyst
Papule or nodule that contains fluid so is fluctuant
Types of scars
Atrophic (sunken depressions due to not enough collagen)
Hypertrophic (opposite, raised due to excess collagen)
Characteristics and clinical features of atopic eczema
Chronic inflammatory condition developing in childhood
Genetic component = increased with asthma + hay fever
Also can be environmentally triggered eg diet + stress
Clinical features = itchy erythematous dry scaly patches on face, extensor aspects of limbs in infants and flexor aspects in children + adults
Pompholyx eczema
Affects the hands with small fluid filled blisters (vesicles)
Eg nickel allergy
What is a bulla
Essentially a vesicle (fluid filled blister) that is larger than 0.5cm in diameter
Characteristics of psoriasis and clinical features
Chronic inflammatory skin disease due to hyper proliferation of keratinocytes and inflammatory cells infiltrating the skin
Caused by complex interaction between genetic, immunological and environmental factors
Precipitating factors include trauma, infection, drugs (beta blockers), stress and alcohol
What is erythroderma
Complication of psoriasis
In erythroderma there is hypothermia and high output heart failure and capillary leak syndrome and fluid loss
What is the Koebner effect and what conditions cause it
A linear eruption arising at the site of trauma phenomenon
Eg psoriasis, plane warts, vitiligo and lichen planus
What is an abscess
Localised accumulation of pus in the dermis or subcutaneous tissues
What is the erythrasma
Common condition that affects the skin folds
Caused by gram positive non-spore forming aerobic bacteria
= pink or brown patches with fine scaling and superficial fissures
Most common skin cancer: basal cell skin cancer
Is a malignant cancer of the epidermal keratinocytes that rarely metastasises
Slow growing
Risk factors include UV exposure, history of severe sun burn, fair skin, increasing age, male sex, immunosuppression, previous history of skin cancer and genetic predisposition
Squamous cell carcinoma characteristics
Caused by dna damage from exposure to ultraviolet radiation or other damaging agents that trigger abnormal changes in squamous cells
Can metastasise
Normally in sun exposed areas of body
Malignant melanomas
Invasive malignant tumour of the epidermal melanocytes which has the potential to metastasise
Causes = fair, excessive UV exposure, history of moles or atypical moles and family history or previous history of melanomas
May itch and bleed
Has worst prognosis
How is breslows depth scale used to measure tumours
Stage 1 = <0.75mm
Stage 2 = 0.76 to 1.50mm
Stage 3 = 1.51 to 2.25mm
Stage 4 = 2.26 to 3.00mm
Stage 5 = >3.00mm
