Dermatology Flashcards
What is the aetiology of eczema?
Eczema is a chronic, relapsing, inflammatory skin condition. Certain triggers can bring it on/exacerbate it
What are some triggers for eczema?
Irritants, skin infections, extremes of temperature, dietary factors, stress, hormonal factors
What is the pathophysiology involved in eczema?
Eczema can be dry, scaly and red. There is lichenification due to constant scratching and rubbing causing hyper-pigmentation, acanthosis and hyperkeratosis.
What are the symptoms of eczema?
An itchy red rash with an extensor or flexural pattern, affects the cheeks first in infants
What are the signs of eczema?
Itch erythematous scaly patches, especially in the flexures
What is the diagnostic criteria for eczema?
Must have had an itchy skin condition in the past 6 months and >/= 3 of:
History of involvement of the skin creases
Personal history of asthma or hayfever (or a 1st degree relative if <4)
History of generally dry skin
Visible flexural dermatitis
Onset before 2 years of age (N/A if child is <4)
What is the treatment for eczema?
Baseline: manage triggers and emollients
Mild: + garments, wet wraps, pastes, bandages, topical corticosteroids and topical calcineurin inhibitors
Moderate: + sedative antihistamines + UV treatment
Severe: + systemic treatments (e.g. azathioprine, cyclosporin)
All stages: antibiotics/antiseptics as needed
What is the aetiology of psoriasis?
Appears to be polygenic but is also dependent on certain environmental triggers e.g. infection, drugs, UV light, alcohol abuse and possibly stress
What is the pathophysiology involved in psoriasis?
It is a papulo-squamous disorder characterised by well demarcated, red scaly plaques. The skin becomes inflamed and hyperproliferates.
What are the two peaks of onset for psoriasis?
16-22
55-60
What are the symptoms of psoriasis?
Red scaly patches with a silver scale, can be on extensor surfaces or flexural surfaces
What are the signs of psoriasis?
Nail changes: pitting, onycholysis, yellow-brown discolouration, subungual hyperkeratosis, damaged nail matrix
What tests are used to diagnose psoriasis?
Diagnosis is clinical and a biopsy is not usually required. Dermoscopy may be useful in differentiating guttate psoriasis from chronic pityriasis lichenoides
What is the treatment for psoriasis?
Emollients, topical vitamin D analogues, topical corticosteroids, topical retinoids, UV B, coal tar preparations, dithranol, methotrexate, ciclosporin, anti-TNF biologics
What is the aetiology of acne?
Genetic factors play a part and positive family history is also a factor, may be associated with PCOS and abnormal production of androgens
What is the pathophysiology of acne?
Key factors: seborrhoea, comedo formation, colonisation of the pilo-sebaceous ducts with P. acnes and inflammation of the pilosebaceous unit
What are the symptoms of acne?
Greasy skin with a mixture of comedones, papules and pustules. Can also present with cysts - can be painful. Acne mostly occurs on the face, back and chest.
What are the signs of acne?
No obvious physical signs.
What tests are used to diagnose acne?
Usually no investigations are required, investigations are occasionally required to explore a possible underlying cause
What is the treatment for acne?
Topical treatments: benzyl peroxide, azelaic acid, topical antibiotics, topical retinoids, nicotinamide
Oral therapies: tetracyclines, erythromycin, trimethoprim, isotretinoin, co-cyprindol
Isotretinoin is teratogenic and has been associated with severe psychiatric side effects