Derm Flashcards
Squamous cell carcinoma summary card
Cancer of keratinocytes in epidermis
= FHx, UV light, lighter skin, acitinic keratosis (pre-cancerous)
= hyperkeratotic, scaly/crust, ulcerated, non-healing, rolled edges
= locally invades into dermis, can metastasise
Basal cell carcinoma summary card
Cancer of keratinocytes epidermis in stratum basale
= FHs, UV light, lighter skin
= nodule w/ pearly edges, rolled edges, central ulcer (rodent ulcer), central fine telangiectasia
= slow growing, local invasion into dermis, barely metastasises
Malignant melanoma presentation
RFs: FHx, UV light, lighter skin
A symmetry
B order (irregular)
C olour (pigmented)
D iameter (>6mm)
E volution (size/shape)
= may also bleed, itch, ulcerate, crust over
Locally invades into dermis, can metastasise (CXR, LFTs, brain MRI, CT chest, abdo + pelvis)
Subtypes of melanoma
Superficial spreading
= most common
Leutigo maligna
= fla lesions often on face (elderly)
Nodular
= domed shape, rapid growth
Acral lentiginous
= palms, soles + nail beds, non-Caucasians
Ix for ?cancer lesions
Physical examination, basic obs
Dermatoscope
Referral (melanoma + SqCC urgent, BCC routine)
Skin biopsy (Clark level/Breslow thickness to see melanoma invasion)
CT/MTI/PET (for staging)
What are melanocytic lesions?
Benign neoplasms of melanocytes via epidermis
= symmetrical lesion, flat, regular borders, does not bleed/itch/ulcerate/crust over
= often congenital or arise during childhood
= RARELY transform into melanomas
How can eczema present?
Dry skin
Itchy, erythematous
Lichenification (if chronic)
Distributed on flexures
Eczema subtypes
Atopic dermatitis
= type I hypersensitivity (IgE), flezures
Contact dermatitis
= type IV hypersensitivity, often nickel/latex, either irritant/allergic trigger
Discoid dermatitis
= coin-shaped/disc lesions, itchy, middle-aged/elderly
Seborrhoeic dermatitis
= distributed eyebrows, nasolabial, scalp (cradle cap)
= yellow, greasy scaly rash in babies often
Dyshidrotic aka pompholyx
= itchy/painful blisters, distributed on palms and plantars
Eczema herpeticum
= medical emergency, super-imposed HSV-1
Psoriasis presentation
Hyperproliferation of keratinocytes result in:
Scaly, purple, silvery plaques
Dry, flaky skin
Itchy/painful
Distributed on extensors and scalp
Nail signs: pitting, onycholysis, subunual hyperkeratosis
RFs: PMHx/FHx of psoriasis, triggers include alcohol, smoking, stress
Psoriasis subtypes
Plaque psoriasis (presentation example)
= most common
Pustular aka palmo-planter
= plaques/pustules on palms + plantars
Guttate psoriasis
= white, scaly, raindrop plaques form on trunks and extremities, often 2 weeks post-strep (URTI)
Flexural
= occurs in body folds; per-anal area, groin, axilla
Erythrodermic
= requires hospitalisation, systemic body reness and inflammation
= often temperature, dysregulation, electrolyte imbalances
Cellulitis vs erysipelas
Cellulitis
= affects dermis and subcutaneous tissue, patchy borders, less commonly has systemic effect, more commonly leads to sepsis
Erysipelas
= affects epidermis (superficial), well demarcated borders, typically fever/rigors, less commonly leads to sepsis
Presentation of cellulitis/erysipelas
Acute onset
Inflammation: painful, red, hot, swollen
RFs: wounds/ulcers/bites, IV cannula, immunocompromised
Complications of cellulitis
Sepsis
Abcess
Necrotising fascitis
Oribital cellulitis*
Periorbital cellulitis*
*visual impairment = medical emergency!!
Ix of cellulitis/erysipelas
Physical examination
Basic obs; ?sepsis
Bloods; increased WCC + CRP
Blood cultures
Pus/wound stab MCS
CT/MRI if orbital cellulitis to identify posterior spread of infection
Mx of cellulitis/erysipelas
Conservative
= monitor obs, oral fluids, draw around lesion to see if it grows/shrinks
Medical
= oral Abx (flucloxacillin) or IV Abx if severe
Admit if
= sepsis (high HR, RR and low BP)
= confusion (assess AVPU, GCS)