General Patton- Cutaneous rxns Flashcards
What is the most common cause of autosensitization dermatitis?
stasis dermatitis
What does DRESS stand for?
Drug Rash Eosinophilia and Systemic Symptoms
What is the most common cause of erythema multiforme?
HSV
Type of hypersensitivity in allergic contact dermatitis
Type IV
What occurs in the sensitization phase of allergic contact dermatitis?
exposure of the immune system to the hapten-peptide complex followed by clonal expansion of reactive T cells
What is dermatographism?
urticaria caused by rubbing or scratching the skin
T/F: there is no need to give systemic corticosteroids in allergic contact dermatitis
false, they are usually given d/t the severe nature of the rash
What is the main determinant of whether urticaria are acute or chronic?
the 6 week time period. If less than 6 weeks = acute, if greater than = chronic
What causes irritant contact dermatitis?
exposure to harsh solvents such as alkali or overexposure to mild solvents
What is the clinical manifestation of allergic contact dermatitis?
eczematous dermatitis = itch, edema, erythema, and vesicle formation if acute/subacute and lichenification if chronic
How can you get a definitive diagnosis of allergic contact dermatitis to everyday materials?
patch testing
When evaluating a patient for allergic contact dermatitis to everyday materials, what is the most important piece of information to receive?
ALL OF THE PRODUCTS THAT THEY ARE USING? It is more likely to be from something they have been using their whole life than something new
How is DRESS different from morbilliform drug reactions?
it involves organs not just skin, most commonly the liver
This is the most common type of drug eruption
Morbilliform drug reaction
What differentiates erythema multiforme minor from major?
the amount of mucosal surface involvement
T/F: if a morbilliform drug eruption occurs then the offending agent must be stopped immediately
false, it may be continued if necessary
What are the autoantibodies against in chronic autoimmune urticaria?
receptors on mast cells
How do you treat irritant contact dermatitis?
minimize exposure, for acute flares = topical corticosteroids, frequent emollient use
What kind of urticaria develop after stressful events?
cholinergic urticaria
What is the most serious complication of DRESS?
fulminant hepatic necrosis
Which plant substance is involved in phytophotodermatitis?
furocoumarins (citrus fruit)
How do you treat allergic contact dermatitis?
topical and SYSTEMIC corticosteroids, systemic antihistamines, and soothing astringent wraps
Which drugs are the most common cause of DRESS, Stevens-Johnson syndrome, and Toxic Epidermal Necrolysis?
Aromatic anti-convulsants, sulfonamide antibiotics, and allopurinol
What immune cells mediate phytophotodermatitis?
none it is not mediated by the immune system but by a phototoxic reaction
What is the most common cause of allergic contact dermatitis?
reaction to toxicodendron plants (i.e. poison ivy, poison sumac)
What is the key feature in the allergic contact dermatitis from plants?
Linear nature of the rash
What is the most common cause of acute urticaria?
upper respiratory infection
Where do fixed drug reactions tend to occur?
genital region
4 general causes of erythema nodosum?
infections, medications (birth control!), IBD, and sarcoidosis
What is the most common cause of the morbilliform drug eruption?
When someone is mistreated with ampicillin when they have mononucleosis (doc thought they had strep throat)
What drugs are most likely to cause fixed drug eruption?
ibuprofen, naproxen, sulfonamides, and tetracyclines
How do you differentiate Stevens-Johnson syndrome from Toxic Epidermal Necrolysis?
less than 10% of body SA is involved in SJS and greater than 30 is involved in TEN? The inbetweeners are a mixed SJS-TEN Dx
