SM_261a: Drug Reactions and Blistering Disorders Flashcards
Drug-induced skin reactions can be ____ or ____
Drug-induced skin reactions can be immediate or delayed
- Immediate: occurs < 1 hour after last administed dose - urticaria, angiodema, anaphylaxis
- Delayed reactions: occurs after 1 hour but usually > 6 hours - exanthematous eruptions, fixed drug eruption, systemic reactions (DRESS, SJS, TEN), and vasculitis
Urticaria can be caused by ____, while angiodema can be caused by ____
Urticaria can be caused by NSAIDs/opiates (pain meds), while angiodema can becaused by ACE inhibitors
(most urticaria is not drug-related)
Urticaria is described as a ____
Urticaria is described as a wheal
(edematous pink plaque that branches)
____, ____, and ____ are the most common delayed adverse drug reactions
Exanthematous, drug-induced hypersensitivity syndrome (DRESS), and epidermal necrolysis (Stevens-Johnson, toxic epidermal necrolysis) are the most common delayed adverse drug reactions
Reactions to aminopenicillins occur most commonly in patients with ____
Reactions to aminopenicillins occur most commonly in patients with EBV infection
This is an ____ drug reaction
This is an exanthematous drug reaction
(rapidly erupting rash that may have specific diagnostic features of infectious disease, classic in measles)
Morbiliform rash is associated with ____
Morbiliform rash is associated with measles
(other exanthems are rubella, roseola infantum / sixth disease / exanthem subitum which is caused by HHV-6)
Exanthematous drug eruption lesions initially appear on the ____ and spread ____
Exanthematous drug eruption lesions initially appear on the trunk and spread centrifugally to the extremities in symmetric fashion
(erythematous macules and papules)
Exanthematous drug reaction resolves ____ and is treated with ____, ____, and ____
Exanthematous drug reaction resolves in a few days to a week after medication is stopped and is treated with topical steroids, oral antihistamines, and reassuranc
Patient with facial edema; diffuse rash; and elevated WBC, eosinophils, and ASTs has ___
Patient with facial edema; diffuse rash; and elevated WBC, eosinophils, and ASTs has drug-induced hypersensitivity syndrome (DRESS)
Drug induced hypersensitivity syndrome / drug reaction with eosinophilia and systemic symptoms (DRESS) is a ___ with ____ symptoms and ____ involvement that appears in the ___ week of treatment
DRESS is a skin eruption with systemic symptoms and internal organ involvement that appears in the 3rd week of treatment
(>70% of patients have eosinophils,
Medications implicated in DRESS include ___, ___, ___, ___, ___, and ___
Medications implicated in DRESS include allopurinol, antibiotics, anti-TB drugs, anticonvulsants, NSAIDs, and anti-HIV drugs
Approach to patient with suspected DRESS is ____
Approach to patient with suspected DRESS is stopping / substituting all suspected medications and discontinuing non-essential medications
- If not severe, can use topical steroids and systemic antihistamines
- If severe, start systemic steroids (prednisone) and gradually taper - steroids are indicated for nephritis and impending organ failure
Erythema multiforme is characterized by ____ that favor ____, ____, and ____
Erythema multiforme is characterized by target lesions that favor palms, soles, and face
Preceding ____ are the most common precipitating factors of erythema multiforme, not usually ____
Preceding HSV or Mycoplasma pneumoniae infection are the most common precipitating factors of erythema multiforme, not usually a drug reaction
This is ____ due to ____
This is erythema multiforme due to Mycoplasma
This is ____
This is epidermal necrolysis
(includes Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis)
Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis are characterized by mucocutaneous ____ and ____ and ____
Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis are characterized by mucocutaneous tenderness and erythema and extensive skin erosion
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis results from ____
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis results from extensive necrosis and detachment of the epidermis
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis occur ____ days after initiation of drugs such as ____, ____, and. ____
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis occur 7-21 days after initiation of drugs such as sulfa, anticonvulsants, and NSAIDs
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis clinical findings include ____, ____, ____, and ____
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis clinical findings include systemic signs, eruption initially symmetric and distributed on the face / upper extremities / proximal extremities, initial lesions characterized by dusky red to purpuric macules (atypical targets), and blistering of dark center of atypical target lesions
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis is treated initially by ____
Stevens-Johnson Syndrome / Toxic Epidermal Necrosis is treated initially by early recognition and withdrawal of the offending drugs
Describe clinical features that warn of potentially severe drug reaction
Clinical features that warn of potentially severe drug reaction
- Systemic: fever, internal organ involvement, lymphadenopathy
- Cutaneous: evolution to erythroderma, prominent facial involvement ± edema or swelling, mucous membrane involvement, skin tenderness / blistering / shedding, purpura
Blister forms from ____
Blister forms from separation of cells either in epidermis or at dermal / epidermal junction
Intraepidermal blisters are ____, while subepidermal blisters are ____
Intraepidermal blisters are flaccid and easily broken, while subepidermal blisters are tense and usually intact
(Nikolsky sign: epidermal separation induced by lateral pressure to edge of blister or normal appearing skin - characteristic for intraepidermal blisters)
Dermatitis herpetiformis is caused by ____, is the skin version of ____, and is treated with ____ and ____
Dermatitis herpetiformis is caused by gluten sensitivity, is the skin version of Celiac disease, and is treated with gluten-free diet and dapsone
(associated with gastric atrophy, thyroid disease, small bowel lymphoma)
Dermatitis herpetiformis results from ____ and is caused by deposition of ____ in the ____, triggering a ____
Dermatitis herpetiformis results from immunologic response to chronic stimulation of gut mucosa by dietary gluten and is caused by deposition of IgA in the papillary dermis, triggering an immunologic cascade
Pemphis vulgaris is when ____ result in ____
Pemphis vulgaris is when autoantibodies against desmogleins in demsomosomes result in superficial bullae and erosions
(flaccid and easily ruptured bullae on skin and mucous memrbanes, IF shows IgG to Dsg3 ± Dsg1, treated with immunosuppression, complication of sepsis)
Pemphigus vulgaris involves ____ and is ____ on immunofluorescence
Pemphigus vulgaris involves intraepithelial split just above the basal keratinocytes and is +IgG on immunofluorescence
Pemphigus foliaceous is more ____ than pemphigus vulgaris
Pemphigus foliaceous is more superficial than pemphigus vulgaris
Bullous pemphigoid is when ____ result in ____
Bullous pemphigoid is when autoantibodies against hemidesmosome result in deep, tense bullae
(can be oral, treated with prednisone / azathioprine / tetracycline / dapsone)
Bullous pemphigoid involves ____ and is ____ on immunofluorescence
Bullous pemphigoid involves subepidermal split and is +IgG/C3 on immunofluorescence
Porphyria cutanea tarda results from issues with ____
Porphyria cutanea tarda results from issues with porphyrins
- Photosensitivity and skin fragility with possible blistering, erosions, crusts, milia, and scars in sun-exposed sites
- Hypertrichosis, scarring alopecia, morpheaform and sclerodermoid changes
