Skin Flashcards
Normal Flora
Coag -ve staph, s aureus, propionibacterium, corynebacterium
HSV
Vesicles ulcerate and release infective particles Lies in DRG as episomes Triggered by infection, stress, UV light Primary infection= painful mouth lesions Secondary infection= peri-oral lesions Treatment= aciclovir
VZV
Shingles trigged by physical or emotional prob
Weeping vesicular rash in dermatome
Treatment= aciclovir
Molluscum Contagiosum
Poxvirus
Small, raised, pearly lesions
Disappear in 6-18 months
Orf
Spread by infected sheep and goats
Lumps on extremities which blister and crust
No treatment needed
Cowpox
Localised and self-limiting
From cats
Blistering hand lesions
Impetigo
Epidermal infection
Causes= s aureus or pyogenes
Get plaque lesions, yellow exudate and thick scabs
Treatment= mupirocin
ETA+B exotoxins may cause scolded skin or bullous impetigo
Erysipelas
Dermal infection
Causes= s pyogenes
On face or shin
Demarcated inflamed lesion
Cellulitis
Infection of skin and subcut
Causes= s aureus, pyogenes, pasteurella and h influenzae
Get unilateral diffuse inflamed lesion
Anthrax
From imported wool and hair
Inoculates through broken skin
Malignant pustule which may become septicaemic
Necrotising Fasciitis
Skin and subcut infection Type 1= polymicrobial (gram -ve bacilli and anaerobes) Type 2= s pyogenes Dark necrotic spreading lesion Need IV meropenem and clindamycin Debridement
Gas Gangrene
Cloristidium perfringens (from lower GI or anaerobic tissue) Like NF
Erythrasma
Brown scaly patches in folds of skin
Caused by corynebacterium
In DM+ obese pts
Need topical fusidic acid or macrolides
Mycobacteria
Fish tank granuloma
Leprosy
Tinea
Corporis= ringworm Pedis= Feet Cruris= Jock itch Capitis= scalp
Onchomycosis
Nail infection
Fungal Causes
Tricphyton and microsporum
Need clotrimazole, terbinafine
Psoriasis
Plaques on extensor surfaces
Fine and silvery
Get arthritis, CVD and skin cancer
SLE
Systemic or discoid
Red scaly patches
Bullous disease
Pemphigus (in epidermis, fragile blisters)
Pemphigoid (in BM)
Dermatitis Herpetiformis
Small itchy blisters
Associated with coeliac
IgA deposited in papillae
Pemphigoid
Porphyria Cutanea Tarda
AD or acquired (Hep C)
Porphyrin buildup causes blisters and scarring
BCC
Causes= sun, radio, immunosuppression
Nodule then ulcer
Rarely mets
SCC
Causes= UV, radio, chronic ulcers, drugs, immunosuppression
Ulcerated crusty nodules
Some met to lip, ear and perineum
Pre-malignant= actinic keratosis
Melanoma
ABCD (asymmetry, borders uneven, colour variation, large diameter)
Causes= sun, race, FH
Breslow thickness indicates prognosis
Treatment= surgery, BRAF inhibitors
Naevi
Benign melanocytes
Superficial or deep
Lentigo Maligna
Slow growing, flat, pigmented patch
Proliferation of atypical melanocytes (can invade dermis and metastasise)
Due to sun damage
