AGEP

Common culprits: penicillins cephalosporins Latency: day to few days

blood neutrophilia, assocaited high fever PINPOINT pustules followed by desquamation

DRESS

Morbiliform rash, typically diffuse and confluent may have facial involvement with purpura systemic symptoms (ie fever, malaise)

BW: classically eosinophilia (>700/ul) in 50-90% (not fully sensitive); atypical lymphocytes; transaminits > renal failure

latency: 2-8 weeks post exposure takes 6-9 weeks to recover

Culprit drugs: anything but classically AEDs and allopurinol HLA associations with certain drugs: HLA-A*31 with carbamazepine, HLA-B*58 and allopurinol

Management is to STOP, but may require steroids or more specialized treatments

SJS/TENS

Hung nature reviews disease primers 2024 - SCAR common and distinct pathophysiologic mechanisms

SJS/TENS mostly caused by drugs but also post-infectious possible EBV especially for SJS

EM - SJS -TEN spectrum

for SJS, involving mainly mucosal (mouth + eyes), it is more likely to be POST infectious etiology - MIRM (or Reactive infectious mucocutaneous eruption - RIME) most common is mycoplasma, but COVID also can cause this. see image

off label - cyclosporine is used often by derms, the texts will use the steroid pulses

EM

note morphology - annular, more dusky persistent darker area in the middle representing longer lasting cytotoxic damage

GBFDE