MPO and Autoimmunity: In liaison with our rheumatology team, the patient underwent an extensive work-up for systemic autoimmune conditions consisting of antinuclear antibodies (ANA), anti-double-stranded deoxyribonucleic acid (anti-dsDNA) antibodies, anti-SSA (Ro) or anti-SSB (La) antibodies, ANCA, proteinase 3 antibodies (PR-3), myeloperoxidase (MPO) antibodies, serum protein electrophoresis (SPEP), anti-phosphatidylserine, and anti-GBM antibodies.