Dermatology Flashcards
What sign is Nikolsky’s sign?
Twisting pencil rubber on skin causes peeling/desquam
Positive: pemphigus
Negative: pemphigoid
First-line management of pityriasis
Topical ketonazole
Antibodies found in coeliac disease
Anti-TTG
Antibodies involved in pemphigus vulgaris
Antibodies against desmoglein III
What are 2 main signs to monitor in a patient with toxic epidermal necrolysis?
Fluid loss, electrolyte imbalances
What would be seen on skin biopsy of dermatitis herpertiformis?
IgA deposition in dermis
Oral therapies for rosacea
Tetracycline
Isotretanoin
First line management for ulcers assoc with rheumatoid and IBS etc
Suggests pyoderma gangrenosum
Oral prednisolone
Management of scabies
Topical permethion
Large red mark on baby’s shoulder which is getting bigger suggests?
Haemangioma
- no management (spontaneously regresses in childhood)
What cell causes wheals/hives?
Mast cells
- due to histamine release, hence the itch
Itchy blisters on extensor surfaces with granular IgA at dermal papillae suggests?
Dermatitis herpetiformis
How can you differentiate between erythroderma and TEN/SJS?
Erythroderma - widespread (90%) erythema, causes fluid loss/hyponatraemia/systemic symptoms, usually pre-existing skin condition
TEN/SJS - drug reaction/viral illness, erythematous blisters that become target signs, Nikolsky positive, involves surfaces e.g. conjunctivae, mouth, GI tract
Most useful investigation in blisters spreading to other sites
Biopsy with immunofluorescence
X-ray signs of psoriatic arthritis
joint space narrowing and periarticular erosions
Presentation of secondary syphillis
Maculopapular rash covering the torso and limbs as well as the palms and soles
Lymphadenopathy and systemic upset
What skin condition can Crohn’s cause?
Erythema nodosum
Small brownish lesion on leg that dimples when squeezed
Dermatofibroma
Differntiating between lichen planus, sclerosis and simplex chronicus?
Lichen planus - lacy white lines with irregular purple plaques on mouth and skin
Lichen sclerosis - inflam/destruction of genital tissue
Lichn simplex chronicus - excessive scractching causing lichenification, thick/leathery/dark skin
Medication for gout causing SJS
Allopurinol
Causative organism in eczema herpeticum
HSV
Lichen planus can cause what nail changes?
Onychorrhexis
- longitudinal nail ridges
Recurrent sinusitis assoc with erythema nodosum
GPA
Management of genital warts
Topical podophyllotoxin