C4A and Hypoalbuminemia: Blood examination revealed hypoalbuminemia (serum albumin of 3.1 g/dL), renal insufficiency (serum creatinine of 0.68 mg/dL), estimated glomerular filtration rate (e-GFR), 70.8 mL/min/1.73 m2, hypocomplementemia (C3, 4 mg/dL, C4, 3.4 mg/dL, and CH50, 10 U/mL) and positive PR3-anti-neutrophil cytoplasmic antibodies (ANCA) (33 U/mL; normal range 0–9 U/mL).