Pathology Part 2 Flashcards
Psoriasis
A chronic autoimmune condition that causes recurrent symptoms of psoriatic skin lesions. There is a large variation in how severely patients are affected with psoriasis.
Psoriasis subtypes
- plaque psoriasis:
- flexural psoriasis
- guttate psoriasis
- pustular psoriasis
Plaque psoriasis features
The most common sub-type resulting in the typical well-demarcated red, scaly patches affecting the extensor surfaces, sacrum and scalp.
Flexural psoriasis features
In contrast to plaque psoriasis the skin is smooth
Guttate psoriasis features
Transient psoriatic rash frequently triggered by a streptococcal infection. Multiple red, teardrop lesions appear on the body
Pustular psoriasis features
Commonly occurs on the palms and soles
General features of Psoriasis
- Nail signs: pitting, onycholysis
- Arthritis
- Well demarcated red scaly plaques
What drugs make psoriasis worse?
- Lithium
- Anti-malarials
- Beta-blockers
Complications of psoriasis
> psoriatic arthropathy
increased incidence of metabolic syndrome
increased incidence of cardiovascular disease
increased incidence of venous thromboembolism
psychological distress
Auspitz sign
Psoriasis - refers to small points of bleeding when plaques are scraped off
Koebner phenomenon
Psoriasis - Refers to the development of psoriatic lesions to areas of skin affected by trauma - typically sternum
Second line treatment for chronic plaque psoriasis
Second-line: if no improvement after 8 weeks then offer: a vitamin D analogue twice daily
First line treatment for chronic plaque psoriasis
A potent corticosteroid applied once daily plus vitamin D analogue
Applied once daily should be applied separately, one in the morning and the other in the evening) for up to 4 weeks as initial treatment
Third line treatment for chronic plaque psoriasis
Third-line: if no improvement after 8-12 weeks then offer either: a potent corticosteroid applied twice daily for up to 4 weeks, or a coal tar preparation applied once or twice daily
Secondary management for plaque psoriasis (in secondary care)
- oral methotrexate is used first-line.
- ciclosporin
- systemic retinoids
- biological agents: e.g infliximab, etanercept and
Plaque psoriasis management
The use of potent topical corticosteroids used once daily for 4 weeks
If no improvement after 4 weeks then either use a different formulation of the potent corticosteroid (for example, a shampoo or mousse) and/or a topical agents to remove adherent scale (for example, agents containing salicylic acid, emollients and oils) before application of the potent corticosteroid
Face, flexural and genital psoriasis management
A mild or moderate potency corticosteroid applied once or twice daily for a maximum of 2 weeks
Vitamin D analogues examples
Calcipotriol (Dovonex), calcitriol and tacalcitol
Dithranol mechanism of action
> Vitamin D analogue - inhibits DNA synthesis
wash off after 30 mins
adverse effects include burning, staining
Uriticaria
o Cutaneous swellings or weals developing acutely over minutes
o Last between minutes and hours before resolving
o Flesh-colored or erythematous
Angioedema
o Oedema around the eyes, lips and hands
o Non-itchy
Treatment for Uriticaria and Angio-oedema
- Avoid salicylates and opiates (as they can degranulate mast cells)
- Oral antihistamines are most useful in treating idiopathic cases
Why are salicylates and opiates avoided in Uriticaria and Angio-oedema?
Avoid salicylates e.g aspirin and opiates (as they can degranulate mast cells)
What drugs cause urticaria?
- aspirin
- penicillins
- NSAIDs
- opiates
Pityriasis rosea
Describes an acute, self-limiting rash which tends to affect young adults.
Aetiology unknown but thought (HHV-7) may play a role.
Management of Pityriasis rosea
Self-limiting - usually disappears after 6-12 weeks
Features of Pityriasis rosea
- Circular or oval pink macules
- More prominent on the trunk than the limbs
- ‘Christmas tree’ pattern on back
- Rash may be preceded by a ‘herald patch’ usually on trunk
Lichen planus
A skin disorder of unknown aetiology, most probably being immune-mediated.
Lichen planus features
- itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms
- rash often polygonal in shape, with a ‘white-lines’ pattern on the surface (Wickham’s striae)
- Koebner phenomenon
- oral involvement in around 50% of patients:
- nails: thinning of nail plate, longitudinal ridging
Lichenoid drug eruptions - causes:
- gold
- quinine
- thiazides
Management of Lichen planus
> Potent topical steroids are the mainstay of treatment
> Benzydamine mouthwash or spray for oral involvement
> Extensive lichen planus may require oral steroids or immunosuppression
Lichen sclerosus
It is an inflammatory condition which usually affects the genitalia and is more common in elderly females. Lichen sclerosus leads to atrophy of the epidermis with white plaques forming
Lichen sclerosus features
- atrophy of the epidermis with white plaques forming
2. Itch is prominent
Management of Lichen sclerosus
- Topical steroids and emollients
2. Follow-up due to increased risk of vulval cancer
Acne vulgaris
A common skin disorder which usually occurs in adolescence. It typically affects the face, neck and upper trunk and is characterised by the obstruction of the pilosebaceous follicle with keratin plugs which results in comedones, inflammation and pustules.
Pathophysiology of Acne vulgris
Characterised by the obstruction of the pilosebaceous follicle with keratin plugs which results in comedones, inflammation and pustules.
What bacteria can be involved in the formation in acne vulgaris?
Anaerobic bacterium Propionibacterium acnes
Features of Acne vulgaris
- Open comedones (blackheads) or closed comedones (whiteheads)
- Inflammatory papules
- Pustules
Acne fulminans
Very severe acne associated with systemic upset (e.g. fever). Hospital admission is often required and the condition usually responds to oral steroids
Mild Acne vulgaris features
Open and closed comedones with or without sparse inflammatory lesions
Moderate Acne vulgaris features
Widespread non-inflammatory lesions and numerous papules and pustules
Severe Acne vulgaris features
Extensive inflammatory lesions, which may include nodules, pitting, and scarring
First line treatment for Acne vulgaris
- Single topical therapy (topical retinoids, benzoyl peroxide)
- Topical combination therapy (topical antibiotic, benzoyl peroxide, topical retinoid)
Second line treatment for Acne vulgaris
Tetracyclines: lymecycline, oxytetracycline, doxycycline
Erythromycin in pregnant, breastfeeding women and in children younger than 12 years of age
Third line treatment for Acne vulgaris
Oral isotretinoin: only under specialist supervision
Pregnancy is a contraindication to topical and oral retinoid treatment
Management of Acne vulgaris in pregnant or breastfeeding women
Erythromycin in pregnant, breastfeeding women and in children younger than 12 years of age
Examples of Keratolytics
Benzyol peroxide
Examples of Topical retinoids
Tretinoin or isotretinoin
Example of oral retinoids
Oral Isotretinoin
Isotretinoin
An oral retinoid used in the treatment of severe acne
Retinoid features
> teratogenicity > dry skin, eyes and lips/mouth > low mood > raised triglycerides > hair thinning > nose bleeds > intracranial hypertension > photosensitivity
Why should isotretinoin treatment not be combined with tetracyclines?
Intracranial hypertension
Acne rosacea
Common inflammatory rash predominantly affecting the face of unknown cause.
Onset usually in middle age and commoner in women
Features of Rosacea
- Affects nose, cheeks and forehead
- flushing
- telangiectasia
- papules and pustules
- rhinophyma
- ocular involvement: blepharitis
- sunlight may exacerbate symptoms
What ocular condition can arise from rosacea?
Blepharitis
First line treatment for mild symptoms of rosacea
Topical metronidazole - i.e. limited pustules and papules
Management of rosacea with predominant flushing but limited telangiectasia
Topical brimonidine gel
Management of severe rosacea
Systemic antibiotics e.g. Oxytetracycline
Management of rosacea with prominent telangiectasia
Laser therapy
Management of rosacea with rhinophyma
Should be referred to dermatology