Revision Checklist Topics Flashcards
Psoriasis - what is it and who gets it?
Long-lasting autoimmune disease characterised by epidermal hyperplasia and increased epidermal turnover, resulting in red, itchy and scaly patches of skin. Cause is known but largely thought to be genetic and triggered by environmental factors
Areas of the body most commonly affected: extensor surfaces (back of forearms, shins, navel area and scalp
Men and women are equally affected and the condition can arise at any age, but most commonly starts in adulthood.
Psoriasis - what are the different forms of this condition and how do they present?
Plaque (psoriasis vulgaris) - approx 90% of cases, presents with red patches and white scales on top
Guttate - drop-shaped lesions
Inverse - red patches form in skin folds
Pustular - small, non-infectious pus-filled blisters
Erythrodermic - widespread rash, can develop from any of the other types
Psoriasis - what changes might be seen in the body, other than the skin?
Nail changes - pitting, changes in colour, subungual hyperkeratosis, onycholysis
In some cases, psoriatic arthritis may also develop
Psoriasis - management
No cure, but various treatments can be employed to help control the symptoms
Steroid creams/Oral steroids
Vitamin D3 creams
UVA light treatment
Immunosuppressives e.g. methotrexate
Worsened by some medications e.g. beta-blockers, NSAIDs
Clinical examination of a rash - what are the three categories than need to be assessed?
Distribution and Configuration
- Widespread or localised?
- Unilateral? Bilateral? Symmetrical?
- Which areas are affected?
- Noticeable pattern in how the lesions are arranged?
Morphology
- Colour
- Size
- Raised or flat?
- Borders
- Surface features e.g. scale, crust
Blanching and Non-blanching rashes - what is the term given to a non-blanching rash? Why does it not blanch? Name one very important condition that presents with a non-blanching rash
Purpura - a purpuric rash is one that does not blanch due to extravasation of blood
Meningitis presents with a non-blancing rash
What terms are used to describe flat lesions?
What term is given to a rash that is completely flat?
Macule if <1cm
Patch if >1cm
A macular rash
What terms are used to describe raised lesions?
What term is used to describe a rash that is elevated?
How about if a rash has areas that are both flat and elevated?
Papule if the elevated area is <0.5cm
Nodule if the elevated area is >0.5cm
A papular rash is one that is raised
If a rash has both flat and elevated areas, it is termed maculopapular
Give some of the different types of nodule that may occur in a raised rash
Plaque - raised edge and flatter surface
Wheal - compressible dermal swelling
Vesicles and Bullae - fluid-filled
Cyst - nodule containing semi-solid material
Pustule - contains pus
Define the following terms…
- Hyperkeratosis
- Parakeratosis
- Acanthosis
Hyperkeratosis - increased thickness of the keratin layer
Parakeratosis - persistence of nuclei in the keratin layer
Acanthosis - thickening of the whole epidermis
From superficial to deep, what are the four layers of the epidermis?
Keratin layer
Granular Layer
Prickle Cell Layer
Basal cell layer
Eczema (aka dermatitis) - what is the common feature of all eczema cases?
What are the two phases of eczema? List some features of each stage
Itch! Common feature of all eczemas
Acute phase - papulovesicular, red (erythematous) lesions, oedema (spongiosis) and ooze or scaling and crusting
Chronic phase - thickening (lichenification), elevated plaques, increased scaling
Name some forms of dermatitis (7)
Contact allergic - delayed (Type IV) hypersensitivity
Contact irritant - trauma e.g. soap, water etc.
Atopic - genetic and environmental factors
Drug-related - Type I or Type IV hypersensitivity
Photo-induced/photo-sensitive - reaction to UV light
Lichen simplex - caused by physical trauma to skin e.g. scratching
Stasis - caused by physical trauma to skin e.g. hydrostatic pressure due to stasis of blood
Contact dermatitis - very briefly describe the pathophysiology of this condition
Upon antigen challenge, specifically sensitised T cells proliferate and migrate to the skin, resulting in inflammation = dermatitis
Contact dermatitis - how is this condition tested for?
Patch testing
How to contact allergic and contact irritant forms of dermatitis differ from one another?
Contact irritant is due to non-specific physical irritation rather than a specific allergic reaction
These two conditions may be difficult to distinguish from one another, and the two may co-exist
Atopic eczema - signs and symptoms
Pruritus (itch)
Ill-defined erythema and scaling
Generalised dry skin
Flexor surface distribution
Associated with other atopic diseases e.g. asthma, allergic rhinitis, food allergies etc.
Atopic eczema - what chronic changes may be seen in this condition?
What does crusting indicate?
Lichenification
Excoriation
Secondary infection. Crusting indicates Staph aureus infection
Atopic eczema - what infectious organism may cause secondary infection in someone with atopic eczema that results in “monomorphic punched-out lesions”?
Herpes simplex virus causing Eczema herpeticum
Atopic eczema - how is this condition diagnosed?
Itching plus 3 or more of the following…
- visible flexural rash
- history of flexural rash
- personal history of atopy
- generally dry skin
- onset before 2 years old