From the Research
Introduction to Hematuria and Subnephrotic Range Proteinuria
Hematuria and subnephrotic range proteinuria are clinical findings that require thorough evaluation to determine their underlying causes.
Definition and Clinical Significance
Hematuria refers to the presence of blood in the urine, which can be microscopic or gross, while subnephrotic range proteinuria refers to the excretion of protein in the urine at levels that are lower than those seen in nephrotic syndrome but still abnormal.
Evaluation Approach
The evaluation of hematuria and subnephrotic range proteinuria involves a stepwise approach that considers the patient's clinical presentation, medical history, and laboratory findings.
Initial Assessment
The initial assessment includes a thorough medical history, physical examination, and basic laboratory tests such as urinalysis and serum creatinine measurement [ 1 ].
- The presence of symptoms such as dysuria, flank pain, or visible hematuria can guide the differential diagnosis.
- Laboratory tests can help identify the presence of proteinuria, hematuria, and other abnormalities such as leukocyturia or casts.
Differential Diagnoses
The differential diagnoses for hematuria and subnephrotic range proteinuria are broad and include:
- Glomerular diseases such as membranous nephropathy [ 2 ]
- Tubulointerstitial diseases
- Urologic disorders such as kidney stones or tumors
- Systemic diseases such as diabetes mellitus or systemic lupus erythematosus
Diagnostic Tests
Diagnostic tests that may be considered in the evaluation of hematuria and subnephrotic range proteinuria include:
- Urine protein-to-creatinine ratio or albumin-to-creatinine ratio to quantify proteinuria [ 3 ]
- Renal ultrasound or other imaging studies to evaluate kidney structure and function
- Renal biopsy to establish a definitive diagnosis in cases where the underlying cause is uncertain [ 4 ]
Management and Treatment
The management and treatment of hematuria and subnephrotic range proteinuria depend on the underlying cause and may involve:
- Medications to control proteinuria and slow disease progression
- Lifestyle modifications such as dietary changes and exercise
- Referral to a nephrologist or urologist for further evaluation and management [ 1 ]
Caveats and Considerations
It is essential to consider the following caveats and considerations when evaluating hematuria and subnephrotic range proteinuria: