Dermatology history- Important pointers:
- Onset and site of symptoms (acute vs chronic) (widespread vs localised)
- Associated symptoms- pain? itch? bleeding? discharge?
- Has the rash spread (+ pattern)?
- Has the lesion changed?
- Relievers and precipitants of symptoms
- Previous and current treatment?
- Constitutional symptoms (weight loss, fever, lethargy)
- Review of all systems
Other important factors which may be relevant (PMH eg. HIV, immunosuppression and skin cancer, Drugs eg. Beta blockers exacerbating psoriasis, Hx of atopy, allergies, family hx and social hx is very important!)
Physical Examination will be covered with the conditions discussed below
Psoriasis
Pathogenesis
- T cell mediated disease
- Epidermal proliferation – causes scale and thickening
- Dilatation and proliferation of blood vessels in dermis causes the erythematous appearance
- Accumulation of neutrophils and T lymphocytes
Background
- Equal incidence in males and females
- Thought to arise from environmental trigger (e.g. trauma, infection, drugs, alcohol, stress) on top of genetic susceptibility
- HLA cw6- strong association with severe disease of early onset.
Types
Acute guttate, chronic plaque, palmoplantar, pustular psoriasis, psoriatic erythroderma
Clinical features of Chronic plaque psoriasis
- Well demarcated erythematous scaly plaques. When scale scratched there can be pin point bleeding (Auspitz Sign)
- Erythema at edge of plaque indicative of active disease.
- Patients can experience post inflammatory hypo/hyperpigmentation
- Nail changes include onycholysis and nail pitting
- Scalp involvement
- 5-30% with psoriasis also suffer from a form of arthritis
Diagnosis
- Clinical
- Skin biopsy if diagnostic confusion (skin biopsy when patient erythrodermic not always accurate- interpret with caution)
Assessment of disease severity
Body surface area estimation (BSA)
Psoriasis area and severity index (PASI)
Dermatology life index quality (DLQI)
Management
- Emollients/bath additives/soap substitutes
- Topical Vitamin D analogues (can be combined with steroid)
- Topical steroid (potent steroid use or withdrawal can cause rebound psoriasis)
- Topical coal tar
- Topical dithranol (works well for thick plaques)
- UVB
- PUVA
- DMARDS and systemic agents e.g. methotrexate, cyclosporine and biologics
Eczema
Eczema and dermatitis are interchangeable terms
Polymorphic inflammatory reaction involving epidermis and dermis
Clinical symptoms and signs
Acute phase – pruritus, erythema, vesiculation, superadded infection
Chronic phase – fissuring, lichenification of skin, excoriations. Predominantly affects flexor areas.
Subtypes
- Exogenous – irritant dermatitis (Occupation history important- healthcare workers and hairdressers with hand dermatitis)
- Endogenous – allergic dermatitis , atopic, discoid (well demarcated coin like lesions with overlying crust and intense pruritus)
- Pompholyx (vesicles on palms and soles)
- Seborrhoeic (PMH important- History of immunosuppression ?HIV, ?Parkinson’s disease)
Treatment
Avoid precipitants – includes soaps, perfumed products
Regular emollient (twice daily)
Topical treatment- steroid and tacrolimus (protopic)
Antihistamine
Antibiotics/antivirals (aciclovir) for superadded infection
UV light treatment
Systemic treatment- Azathioprine/Prednisolone for severe resistant cases
Written by Dr Amna Shah
Resources used to write this document include those listed in the resources section of this webpage.