Management of Hematuria with Proteinuria in Teenagers

Initial Evaluation and Referral

The American Academy of Pediatrics recommends immediate nephrology referral for teenagers presenting with both hematuria and proteinuria, as this combination strongly suggests glomerular disease 1, 2
Verify microscopic hematuria with ≥3 RBCs per high-power field on at least two of three properly collected clean-catch midstream urine specimens 2, 3
Quantify proteinuria using spot urine protein-to-creatinine ratio (normal <0.2 g/g in children; significant if >0.2 g/g on three specimens) 4, 1

The presence of dysmorphic RBCs (>80%) indicates glomerular bleeding 2, 3
Red cell casts are pathognomonic for glomerulonephritis 1, 2
Protein-to-creatinine ratio >1000 mg/g (>1 g/day) requires nephrology evaluation 1, 2

Obtain complete metabolic panel, including serum creatinine, BUN, albumin, and total protein to assess renal function and nephrotic syndrome 4, 3
Complement levels (C3, C4) should be evaluated to assess for post-infectious glomerulonephritis or lupus nephritis 4, 3
Antinuclear antibody (ANA) should be tested if systemic disease is suspected 4

Renal ultrasound is the appropriate first-line imaging modality in teenagers with hematuria and proteinuria to evaluate kidney size, echogenicity, and structural abnormalities 5, 3
Enlarged echogenic kidneys suggest acute glomerulonephritis 5, 3

Refer urgently to pediatric nephrology if persistent significant proteinuria (protein-to-creatinine ratio >0.2 g/g on three specimens) is present 4, 1
Red cell casts or >80% dysmorphic RBCs suggesting glomerulonephritis require urgent referral 4, 1, 2

IgA nephropathy is the most common cause of glomerulonephritis in adolescents, presenting with episodic gross hematuria and persistent microscopic hematuria with proteinuria 3
Post-infectious glomerulonephritis follows streptococcal infection, associated with low C3 levels 3
Lupus nephritis should be considered in females with systemic symptoms 4

The American College of Radiology recommends obtaining an immediate renal ultrasound in adolescents with suspected glomerulonephritis to evaluate kidney size, echogenicity, rule out structural abnormalities, and confirm safety for a percutaneous biopsy. 6
According to the American College of Radiology, the presence of enlarged, echogenic kidneys on ultrasound is supportive of an acute glomerulonephritic process. 7

The American College of Radiology advises that a urine culture should be performed to exclude a concurrent urinary‑tract infection before proceeding to renal biopsy, because sterile pyuria can occur in proliferative glomerular diseases. 6

The American College of Radiology states that imaging is generally unnecessary in patients who have isolated microscopic hematuria without accompanying proteinuria. 8
In the same context, the American College of Radiology also notes that when proteinuria is absent, routine renal imaging can be omitted. 6

The American College of Radiology recommends that a renal biopsy be performed only after ultrasound confirms safe renal anatomy and coagulation studies are within normal limits. 6