Possible causative factors:
(1) drugs such as vancomycin, lithium and diclofenac
(2) underlying malignancy (paraneoplastic)
Clinical findings:
(1) presence of papules, vesicles, small bullae, larger bullae and/or crusted erosions
(2) may progress to toxic epidermal necrolysis (TEN)
(3) mild to moderate pruritus
(4) if drug-induced, there is reversal on discontinuation of the drug and reappearance with rechallenge. However, most physicians do not rechallenge because of the potential risk to the patient.
(5) mucosal involvement, usually oral but also may involve the conjunctiva
(6) absence of evidence for gluten-sensitive enteropathy and the HLA patterns seen with dermatitis herpetiformis
Histologic findings:
(1) subepidermal bulla with neutrophils along the basement membrane with or without eosinophils
(2) linear IgA deposits along the basement membrane on immunofluorescence