A 31-year-old woman comes to the physician for a follow-up appointment. She has a history of recurrent flares of joint pain and low platelets. Today she presents with two small mouth ulcers. Her prior HLA-B27 screening was negative. Serum creatinine and BUN are mildly elevated. Which of the following is most likely to be seen in this patient?
A) Anti-cyclic citrullinated peptide antibodies
B) Anti-microsomal antibodies
C) Decreased serum C3
D) IgM targeting the Fc region of IgG
E) Type II hypersensitivity
