Evaluation of Hematuria and Proteinuria in a Young Female
The presence of both hematuria and proteinuria in a young female strongly suggests a glomerular origin and warrants nephrology referral rather than urologic evaluation, particularly if dysmorphic red blood cells or red cell casts are present. 1
Initial Diagnostic Confirmation
Confirm true microscopic hematuria by documenting ≥3 red blood cells per high-power field on microscopic examination of at least two of three properly collected clean-catch midstream urine specimens 2, 1. Dipstick positivity alone has only 65-99% specificity and requires microscopic confirmation before initiating any workup 1.
Quantify the proteinuria using a spot urine protein-to-creatinine ratio, with normal being <0.2 g/g 1. The combination of proteinuria with hematuria significantly increases the likelihood of glomerular disease compared to hematuria alone 1.
Determining the Source: Glomerular vs Non-Glomerular
Examine the urinary sediment carefully for the following key features 1:
- Dysmorphic red blood cells: >80% dysmorphic RBCs strongly suggests glomerular bleeding 1
- Red blood cell casts: These are pathognomonic for glomerular disease 1
- Urine color: Tea-colored or cola-colored urine indicates glomerular disease, while bright red suggests lower urinary tract bleeding 1
Phase contrast microscopy with observer expertise is required for accurate assessment of RBC dysmorphism, though many laboratories lack this capability 1.
Laboratory Evaluation for Glomerular Disease
If glomerular origin is suspected, obtain the following tests 1:
- Complete metabolic panel including serum creatinine, BUN, albumin, and total protein
- Complement levels (C3, C4) to evaluate for post-infectious glomerulonephritis or lupus nephritis
- Antinuclear antibody (ANA) and ANCA testing if vasculitis is suspected
- Complete blood count with platelets
Imaging Considerations
Renal ultrasound is appropriate to evaluate kidney size, echogenicity, and structural abnormalities 1. Enlarged echogenic kidneys suggest acute glomerulonephritis, while atrophic kidneys with altered corticomedullary differentiation indicate chronic glomerular disease 2, 1.
CT urography and cystoscopy are NOT indicated in the initial evaluation of hematuria with proteinuria when glomerular disease is suspected 2, 1. These urologic evaluations are reserved for isolated hematuria without proteinuria or when non-glomerular bleeding is confirmed.
Indications for Nephrology Referral
Immediate nephrology referral is indicated for any of the following 1:
- Persistent significant proteinuria (protein-to-creatinine ratio >0.2 on three specimens)
- Presence of red cell casts or >80% dysmorphic RBCs
- Elevated creatinine or declining renal function
- Hypertension accompanying hematuria and proteinuria
Special Considerations in Young Females
Exclude menstrual contamination by ensuring urine collection is not during menses, as this is a common cause of false-positive hematuria in women 1. If menstruation is suspected, repeat the urinalysis after menses resolves 2.
Consider IgA nephropathy and post-infectious glomerulonephritis as common causes of combined hematuria and proteinuria in young adults 2, 1. IgA nephropathy is particularly common in young females and can present with episodic gross hematuria coinciding with upper respiratory infections.
Evaluate for systemic diseases including lupus nephritis, which disproportionately affects young women and commonly presents with both hematuria and proteinuria 1.
Common Pitfalls to Avoid
Do not pursue urologic evaluation first when both hematuria and proteinuria are present with features suggesting glomerular disease 1. This leads to unnecessary cystoscopy and CT imaging that will not identify the underlying pathology.
Do not attribute findings to urinary tract infection without confirming infection with urine culture 1. If infection is present, repeat urinalysis after treatment to document resolution; persistent hematuria and proteinuria after infection clearance requires full evaluation 2.
Do not delay evaluation even if symptoms are intermittent 1. Glomerular diseases can present with episodic hematuria but still cause progressive kidney damage requiring early intervention.
Follow-Up Protocol
If initial workup suggests glomerular disease but nephrology referral is delayed, monitor with 1:
- Repeat urinalysis at 6,12,24, and 36 months
- Blood pressure measurement at each visit
- Immediate re-evaluation if gross hematuria develops, proteinuria worsens, hypertension develops, or renal function declines