<unk>  <unk>  is an acute, self-limited skin condition
Peak incidence in second and third decades of life
Despite multiple associations, thought to be triggered by HSV in most cases
Usually self-limited and resolves within 2-6 weeks; may recur
Wide spectrum of severity
Classified as<unk>  minor (skin involvement only) or<unk>  major (involves skin and one or more mucous membranes)
Classified as<unk>  minor (skin involvement only) or<unk>  major (involves skin and one or more mucous membranes)
Infections:
Viral: HSV, hepatitis, influenza A
HSV responsible for ~70% of cases, making it the most common etiology
Fungal: dermatophytosis, histoplasmosis, coccidioidomycosis
Bacterial: streptococcus, mycoplasma, tuberculosis
Drugs:
Antibiotics (penicillin, sulfonamides), anticonvulsants (phenytoin, barbiturates), NSAIDS, aspirin, anti-tuberculosis meds, allopurinol, etc.
Collagen Vascular Disorders:
RA, SLE, dermatomyositis, polyarteritis nodosa
Others:
Pregnancy, cold weather, sunlight, contact exposure, foods, malignancy, hormonal
Viral: HSV, hepatitis, influenza A
HSV responsible for ~70% of cases, making it the most common etiology
Fungal: dermatophytosis, histoplasmosis, coccidioidomycosis
Bacterial: streptococcus, mycoplasma, tuberculosis
HSV responsible for ~70% of cases, making it the most common etiology
Antibiotics (penicillin, sulfonamides), anticonvulsants (phenytoin, barbiturates), NSAIDS, aspirin, anti-tuberculosis meds, allopurinol, etc.
RA, SLE, dermatomyositis, polyarteritis nodosa
Pregnancy, cold weather, sunlight, contact exposure, foods, malignancy, hormonal
Erythema multiforme
Positive Nikolsky’s sign
Cold urticaria
Febrile
Cutaneous larva migrans
Staphylococcal scalded skin syndrome 
Herpetic whitlow
Toxic epidermal necrolysis/SJS 