Dermatology · Pathway 2
Psoriasis
Key points
- Chronic plaque psoriasis: well-demarcated erythematous plaques with silvery scale, extensor surfaces/scalp/sacrum; Koebner phenomenon (lesions at trauma sites); Auspitz sign (bleeding points on scale removal).
- Guttate psoriasis: 'raindrop' lesions after streptococcal throat infection — often self-limiting.
- Nail changes: pitting, onycholysis, oil-drop sign; psoriatic arthritis in ~10–20%.
- Topical first-line: vitamin D analogues (calcipotriol) ± topical steroids; coal tar/dithranol traditional.
- Severe (PASI/DLQI high): phototherapy → methotrexate, ciclosporin, acitretin → biologics (anti-TNF, anti-IL17/23).
Decision points in this pathway
- Guttate (raindrop) pattern post-sore throat?
- Severe/extensive?
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