linear IgA dermatosis


linear IgA dermatosis

An autoimmune, subepidermal vesiculobullous disease that may be idiopathic, drug-induced (especially by vancomycin) or triggered by a preceding infection or cancer. It is similar to bullous pemphigoid dermatitis herpetiformis, associated with HLA-B8 and gluten sensitivity and linear deposition of IgA along the basement membrane, and often has circulating IgA antibodies against part of the 180-kD bullous pemphigoid antigen BPAg2. Remission occurs in 64% of children within 2 years of onset (average age of child onset, 4 years) and 48% of adults within 5–6 years of onset (average age of adult onset, 52).
Clinical findings
Prolonged prodromal itching, transient pruritus or burning before lesions appear; ocular manifestations are characterised by pain, grittiness or discharge. Bullae may be chronic or appear acutely, as seen in drug-induced disease. Lesions in children are typically located over the lower abdomen and anogenital region; in adults, the lesions overlie the trunk and limbs.
Diagnosis
Linear IgA deposition along the basement membrane by direct immunofluorescence.
Management
Leave bullae intact; cover ruptured lesions and erosions with sterile dressings.