Inflammatory Skin Conditions - Erythema multiforme, Erythema nodosum, Hidradenitis suppurativa, Lichen planus, Lichen sclerosus, Hives, Bullous Pemphigoid, Pemphigus Vulgaris Flashcards
Erythema multiforme
-what is it
-presentation
-causes
-management
Hypersensitivity reaction commonly triggered by infection
Target lesions
-back of hands, feet before spreading to torso
-greater upper limb involvement
-mild itch
Virus - HSV (MOST COMMON)
Bacteria - mycoplasma, strep
Idiopathic
Drugs - penicillin, carbemazepine, NSAID, OCP
AI - SLE, sarcoid
Malignancy
Clinical diagnosis
Address underlying cause and symptom management
Erythema nodosum
-what is it
-presentation
-causes
-management
Inflammation of subcut fat
Tender, erythematous, nodular lesions
-often shins, or forearms, thighs
Infection - strep, TB
AI - sarcoid, IBD, Behcet
Malignancy
Drugs - penicillins, sulphonamides, COCP
Pregnancy
Self limiting, healing without scarring
Hidradenitis suppurativa
-what is it
-risk factors
-presentation
-investigations
-management
Blockage of hair follicles around areas with many sweat glands
-chronic painful inflammation in skin folds
FHx
Smoking
Obesity, DM, PCOS
Mechanical stretching of skin
Recurrent, painful, inflammed nodules
Skin folds - especially axilla, inguinal, inner thighs, perineal
Nodules
-rupture of purulent discharge
-coalesce into plaques, sinus tracts, rope-like scarring
Clinical diagnosis
Conservative
-good hygiene, loose fitting clothes
-smoking cessation
-weight loss
Medical
Acute - CS or fluclox
Long term - TOP clindamycin, PO lymecycline or clindamycin+rifampicin
Surgical incision and drainage if persistent
Lichen planus
-what is it
-presentation
-causes
-management
Immune mediated
Itchy papular rash on palms, soles, genitalia, flexors
-red, pink, purple
Oral mucosa
Polygonal rash with white lines
Koebner phenomenon
1st line - TOP CS
Oral involvement - benzydamine mouthwash/oral spray
If severe - PO CS or immunosuppression
Lichen sclerosus
-what is it
-presentation
-diagnosis
-management
-why do we worry about it
Inflammatory condition affecting genitalia, often in older women => atrophy of epidermis with white plaques
Not contagious
White patches that scar
ITCHY!
Pain on urination/intercourse
In males - can make retraction hard
Clinical diagnosis but biopsy can confirm if atypical presentation
TOP CS and emollients
Increased risk of vulval cancer
Pyoderma gangrenosum
-what is it
-presentation
-causes
-investigations
-management
Non infectious, inflammatory skin disorder
Idiopathic in 50%
IBD, RA, SLE
Haem
-MPD, lymphoma, myeloid leukemias
Acute present on lower limb
Small pustule, red bump, blood blister
Skin later breaks down => painful, purple ulcer
-deep necrotic
Systemic symptoms - fever, myalgia
Clinical diagnosis
1st line - PO CS
Immunosuppresants used in difficult to control cases
Hives
-what is it
-common causes
-presentation
-management
Local/generalised superficial skin swelling
Allergy
Pale pink raised, itchy skin
1st line - non-sedating antihistamines (loratidine, ceterizine), continue for 6wks
If symptoms affecting sleep - add sedating antihistamine (chlorphenamine)
If resistant/severe - pred
Contact dermatitis
-irritant vs allergic
-presentation
-management
Irritant - direct damage from substances like weak acids/alkalis - detergents, soaps
-acute onset
-appears after 1st exposure
-burning, stinging, itch, pain, red
-well defined to site of exposure
CLINICAL DIAGNOSIS
Allergic - T4 reaction of sensitisation and reaction
-acute/subacute/chronic onset
-ITCH!
-poorly defined
-weeping eczema
PATCH TEST - to differentiate between irritant and allergic
Avoid triggers
Emollients - moisturise
TOP CS - relieve severe symptoms
If severe - PO CS
Eczema
-risk factors
-presentation
-management
Atopic triad in families
Triggered by soap, detergents, stress, weather
Relapsing remitting
Itchy, dry, cracked, sore skin
Infants - face, trunk
Young children - extensors
Older children - flexors
Avoid scratching, triggers
Emollients
TOP CS - hydrocortisone, betamethasone, clobetasone, fluticasone
Wet wrapping over large amounts of emollient (and TOP CS)
Psoriasis
-risk factors
-presentation
-management
Genetic
Environmental
-skin trauma, stress, strep infection
-improved by sunlight
Plaque - well demarcated, red scaly patches on extensor surfaces
Flexural - smooth skin
Guttate - triggered by strep infection, teardrop lesions
Pustular - palms and soles
Nail pitting, onlycholysis
Arthritis
Initial - 4wks
-TOP CS + VitD analogue OD
2nd line - 4wk CS break to reduce SE
-TOP CS + VitD analogue TDS
Seborrhoeic dermatitis
-epidemiology
-pathophysiology and risk factors
-presentation
-management
30-40s males
Inflammatory reaction to proliferation of fungus Malassezia furfur
-HIV
-PD
Eczematous lesions on sebum rich areas
-scalp, periorbital, auricular, nasolabial folds
OE, blepharitis
Ketoconazole
Bullous pemphigoid
-what is it
-presentation
-investigations
-management
AI - subepidermal blistering of skin
AB against hemidesmosomal proteins
Elderly patients
ITCHY TENSE blisters around flexures => heal without scarring
NO MUCOSAL INVOLVEMENT
Skin biopsy - immunofluorescence of IgG and C3 at dermoepidermal junction
Refer to dermatology for biopsy and confirmation of diagnosis
PO CS
Can use TOP CS, immunosuppression, ABx
Pemphigus vulgaris
-what is it
-presentation
-investigations
-management
AI - mucosal and skin blistering
AB against epithelial cell adhesion molecules
Middle aged or older
MUCOSAL ulceration
FLACCID, NON ITCHY blisters- months after mucosal symptoms
Biopsy - acantholysis (loss of cohesion between keratinocytes)
Refer to dermatology
CS + immunosuppresion
