IgA mediated bullous dermatoses are disorders in which the immune system makes a lot of immunoglobulin A (IgA), an antibody that fights bacteria, toxins, and viruses. There are two types:
Dermatitis herpetiformis affects people with celiac disease. It causes clusters of itchy blisters on the elbows, knees, scalp, and buttocks.
Linear IgA disease causes new blisters to form a ring around old ones on the skin. This is sometimes called a “cluster of jewels.” It affects mucous membranes, too.