C4A and Hypoalbuminemia: Laboratory results revealed hypoalbuminemia and infection, as indicated by white blood cell count of 10.36 × 103 cells/μl (78.2% neutrophils), C-reactive protein level of 40.14 mg/l, serum ferritin level of 422 ng/ml, procalcitonin level of 0.09 ng/ml, erythrocyte sedimentation rate of 37 mm/h, albumin level of 2.3 g/dl, immunoglobulin E level of 366 IU/ml, complement C4 level of 0.51 g/l, complement C1q level of 0.296 g/l, and N-terminal pro-brain natriuretic peptide level of 532.60 pg/ml.