DRUG-INDUCED LINEAR IGA DISEASE WITH ANTIBODIES TO COLLAGEN-VII

Linear IgA disease (LAD) is characterized by circulating and tissue-bo und IgA antibodies against heterogeneous antigens in the cutaneous bas ement membrane zone. In most cases the cause is unknown. but a minorit y of cases has been drug induced, We report a 76-year-old man who deve loped an acute blistering eruption following high-dose penicillin trea tment for pneumococcal septicaemia. Indirect immunofluorescence demons trated dermal binding IgA antibodies, and Western blotting of serum sh owed reactivity with a 250 kDa dermal antigen corresponding to collage n VII of anchoring fibrils. Indirect immunoelectron microscopy showed antibody labelling in the lamina densa and sublamina densa zone. This is one of the few cases of drug-induced LAD in which the target antige n profile has been characterized, and the first in which the antigen h as been shown to correspond to collagen VII.