MPO and Increased total eosinophil count: Laboratory studies (Table 1) performed upon presentation to the rheumatology clinic were notable for elevated sedimentation rate (54 mm/Hr) and C-reactive protein (6.5 mg/dL), leukocytosis (white blood cell count 20.1 K/uL) with peripheral eosinophilia (absolute eosinophil count 8.2 K/uL; note he had mild intermittent eosinophilia for five years prior to presentation), positive cytoplasmic anti-neutrophil cytoplasmic antibody (C-ANCA) 1:40 and myeloperoxidase (MPO) antibody (472 CU), elevated serum IgG (1795 mg/dL) and serum IgG4 (631 mg/dL).