Drug Eruptions

Question 1

presents within minutes to hours of ingestion; transient, pruritic erythematous edematous plaques anywhere on the body: wheals

Answer 1

Acute Urticaria

Question 2

skin disorder due to mast cell degranulation and release of histamine

Answer 2

Acute Urticaria

Question 3

tx for acute urticaria

Answer 3

Stop the offending medication, H1 antihistamines, +/- second-generation H1 antihistamines, +/- prednisone taper

Question 4

Presents 7-14 days after initial medication exposure; likely due to drug or drug peptide hapten is presented by dendritic cells to T cells (cytotoxic); Type 4 hypersensitivity

Answer 4

Morbilliform drug eruption

Question 5

Maculopapular rash- symmetrically distributed erythematous macules and papules on the trunk and upper extremities which then coalesce to become confluent

Answer 5

Morbilliform (Most Common)

Question 6

TX for Morbilliform (Most Common)

Answer 6

Stop offending medication and will slowly resolve over 1-2 weeks; sometimes topical steroids for pruritus. (New lesions can appear even after stopping the meds b/c of gravity.)

Question 7

Caused by aromatic anticonvulsants, sulfonamides, antiretrovirals, allopurinol; RegisSCAR scoring system is used to make a diagnosis; hypereosinophilia; Develops 2-6 weeks after drug exposure

Answer 7

DRESS

Question 8

Rash has a morbilliform appearance but then becomes more edematous with follicular prominence on the face, upper trunk, extremities

Answer 8

Drug Reaction with Eosinophilia and systemic symptoms

Question 9

Internal impact is involved (especially hepatic); any organ system can be affected; symptoms can last for weeks to months after medication withdrawal

Answer 9

DRESS

Question 10

Diagnosis and TX for DRESS

Answer 10

Assessment/Diagosis:

• RegiSCAR scoring
• CBC w/diff (eosinophilia)
• peripheral blood smear (atypical lymphocytes)
• LFTs (hepatic dysfunction)
• BUN/creatinine (kidney dysfunction)

Tx:
- Systemic steroids

Question 11

Time from exposure <4 days; commonly due to macrolides, beta-lactam antibiotics, and calcium channel blockers; high fever

Answer 11

Acute Generalized exanthematous pustulosis (AGEP)

Question 12

Erythema starts on the face and in intertriginous areas then quickly spreads over a few hours; numerous non-follicular based sterile pustules

Answer 12

AGEP

Question 13

Onset a few days to few weeks after initial exposure, subsequent exposure lesions appear at the same site

Answer 13

Fixed Drug Eruption

Question 14

One or few rounds to oval sharply demarcated erythematous to dusky patches +/- bullae

Answer 14

Fixed Drug Eruption

Question 15

Common causing agents/drugs of Fixed Drug Eruption

Answer 15

NSAIDs/acetaminophen/aspirin, sulfonamides, PPIs, tetracyclines

Question 16

Epidermal detachment due to extensive keratinocyte death via apoptosis; Usual onset 7-21 days after medication exposure; Positive Nikolsky sign; Erythema and erosion of buccal, ocular, and genital mucosae present in > 90% SJS/TEN patients

Answer 16

Steven Johnson Syndrome/ Toxic Epidermal Necrolysis

Question 17

Common causing agents of SJS/TEN

Answer 17

Sulfonamides (BACTRIM), anticonvulsants, NSAIDS, antiretrovirals, allopurinol

• same causing drugs as DRESS

Question 18

What prodrome symptom precedes SJS/TEN?

Answer 18

upper respiratory tract symptoms

Question 19

What drug eruption involves mucocutaneous symptoms?

Answer 19

SJS/TEN

Question 20

Tx for SJS/TEN

Answer 20

stop offending drug; ICU/burn unit supportive care

Question 21

what drug eruption has a high risk for infection, is hemodynamically unstable, and has impaired thermoregulation?

Answer 21

SJS/TEN

Question 22

How long does re-epithelization take for SJS/TEN?

Answer 22

starts in days and usually complete in 3 weeks