Elevated IgA is associated with treatment failure and bleeding. (A) Subjects with an IgA greater than median had a significantly increased chance of failing to respond to standard treatment relative to subjects with an IgA less than median. (B) Subjects with an IgA in the third quartile were most likely to fail to respond to standard therapy. (C) Subjects with an IgA greater than median had no difference in response to splenectomy than subjects with an IgA less than median. (D) Subjects with an IgA greater than median had a higher proportion of major bleeding than subjects with an IgA less than median.