Dermatology Flashcards
How do you describe lesions?
Flat = macule or patch
Fluid-filled = vesicle <0.5cm, pustule or bulla >0.5cm
Raised = papule <0.5cm or nodule >0.5cm
RFs for SqCC
UV light, FHx, ligher skin and acitinic keratosis
Describe SqCC lesion and invasion?
Lesion = hyperkeratotoic, scaly, crusty, ulcerated, non-healing and rolled edges.
Inasion = local dermis and can metastasise to LLBB lungs liver bone brain
BCC RFs?
UV light, Fhx and ligher skin
BCC lesion and invasion?
Lesion = nodule, pearly edges, rolled edges, central ulcer (rodent ulcer) and central fine telangiectasia
Invasion = slow growing, local invasion and does not typically metastasise
4 subtypes of BCC?
Nodular = most common
Superficial = flat shape
Morpheic = yellow waxyplaque, scar like
Pigmented = dense colour, specks of colour ?melanoma
Melanoma RFs?
UV light, Fhx and lighter skin
Melanoma lesion and invasion description?
ABCDE Asymmetry Border (irregular) Colour (pigmented) Diameter Evolution (size/shape)
Local inasion and can metastasise LLBB
What are the subtypes of malignant melanoma?
Superficial spreading = most common
Nodular = domed shape and rapid growth
Lentigo maligna = flat lesions on face and elderly
Acral lentiginous = pals, soles and nail beds in non-caucasians
Ix for cancerous lesions?
Melanoma and SqCC = 2WWR. BCC = 6WW
Physical exam and obvs. Dermatoscope.
Bloods = calcium and ALP for bone mets and LFT for liver.
Imaging of CT for staging
Biopsy = breslow thickness for melanoma invasion
What are melanocytic naevi and description?
Benign neoplasm of the melanocytes in eidermis
Often congenital and arise during childhood
Symetrical, flat, regular borders.
Not ABCDS
Eczema risk factors and triggers?
PMHx or FHx of atopy e.g. food allergy, hayfever and asthma.
Filaggrin gene mutation.
Triggers = soaps, shampoos, food allergies, pollen, ouse dust ,mite and pets
Describe eczema lesion?
Dry skin, itchy, erythermatous, distribution on flexures and lichenification if chronic
What are the subtypes of eczema?
Atopic dermatitis = Type 1 and 4 sensitivity (Ig-E mediated). on the flexures
Contact dermatitis = Type 4 hypersensitivity. Often nickel or latex. Two types: irritant and allergic
Discoid dermatitis = middle aged/elderly and coin-shaped plaques
Other Eczema types?
Seborrhoeic dermatitis = yellow, greasy, scaly rash. Distribution eyebrows, nasolabial and scalp (cradle cap)
Dyshidrotic (pompholyx) = itchy painful blisters and on palms and plantars
Eczema herpeticum = superimposed HSV-1`
Psoriasis RFs and triggers?
Hyperproliferation of keratinocytes.
PMHx and FHx or psoriasis.
Triggers = stress alcohol and smoking
Describe psoriasis lesion and nail signs?
Purple, silvery plaques. Dry, flaky skin. Itchy and painful and distributed on extensors and scalp
Nail signs = oncholysis, pitting and subungual hyperkeratosis.
Psoriatitc athritis = symetrical polyarthritis
Oncholysis DDx?
Psoriasis, fungal infection, trauma and thyrotoxicosis
Psoriasis subtypes?
Plaque = most common and previous description
Guttate = raindrop plaques (often 2 weeks post strep
Flexural = body folds e.g. axilla, groin
Pustular AKA palmo-plantar and where it says
Erythrodermic = systemic body redness and inflammation with temp dysregulation, electrolyte imbalances and requires hospitalisation
Inflammatory Ix?
Physical ecam and basic obvs
Bedside tests like skin patch testing for contact dermatitis and IgE RAST bloods for atopic dermatitis
Skin prick testing for food allergies
Describe similarities of cellulitis and erysipelas?
Acute onsent and inflammed.
RFs = wounds, ulcers, bites, IV cannula and immunosuppresion
Cellulitis Specifics?
Dermis and subcut tissue. More patchy borders, less common systemic and more common for sepsis
Erysipelas specifics?
Epidermis , well demarcated, systemic fevers and rigors and uncommon cause of sepsis
Complications of cellulitis?
Abscess, sepsis, necrotising fasciitis
periorbital cullulitis and orbital cellulitis
Ix for cellulitis and erysipleas?
Physcial exam and obvs
Skin swab MCS
Bloods for high WCC, CRP and blood culture and swab show strep pyogenes or staph aureus
Imaging of CT/MRI for orbital cellulitis
Management of cellulitis/erysipelas?
Conservative = draw around, oral fluids, analgesics and monitor obvs
Medical = oral Abx (flucloxacillin and if severe of eye co-amoxiclav
Admit if septic or confused
Describe erytherma nodosum?
Bilateral nodules, tender, red or purple and on anterior shins or knees.
Do not ulcerate or scar
Causes of erytherma nodosum?
Infections = s.pyogenes, TB and HIV
Systemic = IBD and sarcoidosis and Behcets
Drugs = sulphonamides
Pregnancy
Describe molluscm contagiosum?
Skin infection due to molluscum contagiosum virus causing smooth papule and umbilicated. usually painless and often itch
RFs and transmission of molluscum contagiosum?
Immunocompromised e.g. HIV and close contact e.g. sex and swimming pools
Description of erytherma multiforme?
Target lesions = central vesicle and crust, ring of pallor and ring of erytherma
Distributed on hands and then spread
Symptoms and causes of erytherma multiforme?
Prodome (fever and aches) and tender/itchy and pain
Causes = infections (HERPES, Mycoplasma and HIV)
Drug reation e.g. sulphonamides
Ix for erytherma nodosum, multiforme and molluscum contagiosum?
Physical exam and basic obvs.
Maybe HIV and underlying cause diagnosi
