Dermatology Flashcards
What is characteristic about dermatophyte (ringworm, tinea) infections?
Annular appearance
What is the finding on Z Neehson stain in multibacillary leprosy
Acid fast bacilli
What drugs exacerbate psoroiasis
B blockers, antimalarials and lithium
What rash is most associated with mycoplasma pnuemonia
Erythema multiforme. also associated with HSV, HIV and hepatitis
psoriasis is an independent risk factor for CV disease true or flase
TRUE
Causes of erythema nodosum
TB, IBD, sarcoidosis, strep infections, sulfonamides, OCP and pregnancy
What causes photosensitivity, blisters causing scars and milia in the context of chronic liver disease
porphyria cunea tarda - test is urine uroporphorin
What cell type is most implicated in psoriatic epidermal inflammatory response
T cells - induce keratinocyte proliferation. Upgraded production TNF Alpha interferon gama and I’ll - 12
Which genotype means that chinese population are at increased risk of developing TEN with carbamezapine
HLA B 1502.
Management of TEN is with fluids, steroids and anticoagulation (dehydration clot risk)
What condition is dermatitis herpeteformis linked with
Coeliac’s disease - tx dapsone
What dermatological condition is linked with NH lymphoma
paraneoplastic pemphigus
Difference between pemphigus and pemiphigoid
pemphigus - flaccid blisters that rupture more easily. Also more likely to involve MMs and antidesmoglein 1 and 3 antibodies can be measure. Associated with C3 deposition. Whereas pemphigioid are tense more intact blisters and antibodies directed at the basement membrane
What condition is associated with ovoid hypopigmented maculed (ash leaf macules)
tuberous sclerosis. periungual fibromata also arise from nail folds. fundoscopy may show rentinal hamartoma
Causes of TEN
Allopurinol, aspirin, phenytoin, NSAIDs, lamotrigine, lanzoprazole and penicillins
What is pathophysiology of bullous pemphigoid?
autoantibodies to hemidesmosome proteins which attach basal keratinocytes
What is erythroderma?
inflammatory skin condition covering >90% skin surface
mostly psoriasis, eczema, drug eruption, cutaneous lymphoma and piryriasis rubra pilaris
Antibodies associated with SLE
Anti nuclear antibody (ANA), anti dsDNA, Anti Sm, Ro/SSA, La/SSA and u1 RNP
What are the three Ds associated with pellagra
photosensitive dermatitis, diarrhoea and dementia
What is the gene test for marfan’s syndrome
fibrillin 1 gene testing
What is the special stain for pseudoxanthoma elasticum
van kossa stain - patients have plucked chicken skin around neck, loose folds fo skin under axillae and angioid streaks on retinal examination. predisposed to GI bleeding
Autoantibody for primary biliary cholangitis
anti mitochondrial antibody
With which skin condition is pyoderma gangrenosum seen
CML - cribiform pattern of scarring with deep red necrotic ulcers. Also other myeloproliferative disorders, iBD, RA, GPA and lymphoma
What bacterial pneumonia is associated with erythema multiforme?
mycoplasma pneumoniae
Features of dermatomyositis
Guttrons papules, helitrope rash, linear violaceous changes over dorsal surfaces fingers, nail fold inflammation with dilated capillaries
