Other common indications include significant proteinuria (>0.5 g/g creatinine in urine) accompanied with hypertension or elevated serum creatinine, combined hematuria and proteinuria in the presence of red flags such as normal C3 levels, acute kidney injury (AKI) that is not improving, hypertension, or family history of CKD (4). This evidence concerns the gene C3 and hypertensive disorder.