Overview
Definition:
Hematuria is the presence of red blood cells (RBCs) in the urine, which can be microscopic (detected only by urinalysis) or macroscopic (visible to the naked eye)
Proteinuria is the presence of abnormal amounts of protein in the urine, often detected by dipstick testing and confirmed quantitatively.
Epidemiology:
Microscopic hematuria is found in 0.5% to 3% of healthy school-aged children
Macroscopic hematuria is less common
Proteinuria is also prevalent, with transient forms being common, but persistent or significant proteinuria requires investigation.
Clinical Significance:
The presence of hematuria and/or proteinuria in children can indicate a wide spectrum of conditions, ranging from benign and self-limiting causes to serious renal diseases requiring prompt diagnosis and management
Early identification is crucial to prevent long-term renal damage and complications.
Clinical Presentation
Symptoms:
Gross hematuria (pink, red, or cola-colored urine)
Microscopic hematuria may be asymptomatic
Proteinuria is usually asymptomatic
Associated symptoms may include flank pain
Edema (facial, periorbital, sacral)
Hypertension
Fever
Rash
Arthralgias
Malaise
Decreased urine output
Dysuria
Urgency.
Signs:
Vital sign abnormalities: Hypertension is a key finding in many renal diseases
Edema: Periorbital, peripheral, ascites, pleural effusions
Abdominal distension
Pallor
Rash (especially in systemic diseases)
Tenderness in the costovertebral angle
Fluid overload signs
Growth retardation in chronic conditions.
Diagnostic Criteria:
Hematuria: Presence of >3-5 RBCs per high-power field (HPF) on microscopic examination of at least two to three clean-catch midstream urine samples
Dipstick positivity for blood (false positives can occur)
Proteinuria: Dipstick positivity for protein (qualitative)
Quantitative measurement showing urinary protein excretion > 4 mg/m²/hour or a urine protein-to-creatinine ratio (UPCR) > 0.2 in a spot urine sample in children > 2 years old.
Diagnostic Approach
History Taking:
Detailed history is paramount
Onset and duration of symptoms
Color of urine
Presence of pain (dysuria, flank pain)
Recent infections (especially streptococcal)
Trauma to the urinary tract
Family history of kidney disease, hearing loss, or eye abnormalities
Medications
Recent vaccinations
Associated systemic symptoms (fever, rash, joint pain)
Fluid intake and output
Previous urinary tract issues.
Physical Examination:
Thorough general examination including vital signs (BP is crucial)
Assess for edema (location, severity)
Examine skin for rashes
Palpate abdomen for masses or tenderness
Auscultate heart and lungs for murmurs or crackles
Assess for signs of systemic illness
Examine ears and eyes if relevant to syndromes.
Investigations:
Urinalysis: RBCs, WBCs, casts (RBC casts suggestive of glomerular origin, WBC casts for pyelonephritis, hyaline casts may be normal or indicate dehydration)
Proteinuria quantification (UPCR is preferred over 24-hour collection)
Urine culture and sensitivity: To rule out UTI
Complete blood count (CBC): Assess for anemia, infection
Renal function tests: BUN, creatinine, electrolytes
Serum albumin: To assess for nephrotic syndrome
Antistreptolysin O (ASO) titer and anti-DNase B titer: If post-streptococcal glomerulonephritis is suspected
Complement levels (C3, C4): May be low in certain glomerulonephritides
Imaging: Renal ultrasound is usually the initial imaging modality to assess kidney size, structure, rule out hydronephrosis or masses
Voiding cystourethrogram (VCUG) may be indicated if recurrent UTIs or reflux is suspected
Renal biopsy: Indicated for persistent or significant proteinuria, or hematuria with declining renal function, to establish a definitive diagnosis of glomerular disease.
Differential Diagnosis:
Urinary tract infection (UTI)
Post-infectious glomerulonephritis (e.g., post-streptococcal)
IgA nephropathy
Hemolytic uremic syndrome (HUS)
Systemic lupus erythematosus (SLE)
Henoch-Schönlein purpura nephritis
Hereditary nephropathies (e.g., Alport syndrome)
Congenital anomalies of the kidney and urinary tract (CAKUT)
Nephrolithiasis
Trauma
Exercise-induced hematuria
Benign familial hematuria
Minimal change disease
Membranous nephropathy
Focal segmental glomerulosclerosis.
Management
Initial Management:
Focus on identifying the underlying cause
Ensure adequate hydration
Monitor blood pressure closely and manage hypertension aggressively
If UTI is suspected, initiate appropriate antibiotics
If signs of fluid overload or renal dysfunction are present, fluid and electrolyte balance management is critical
Referral to a pediatric nephrologist is often indicated, especially for persistent or significant findings.
Medical Management:
Treatment is cause-specific
Antibiotics for UTI
Immunosuppressants (e.g., steroids, cyclophosphamide) for certain types of glomerulonephritis or lupus nephritis
Antihypertensives (e.g., ACE inhibitors, ARBs) are often used to reduce proteinuria and protect renal function
Diuretics for fluid overload
Dietary modifications may be necessary for specific conditions.
Surgical Management:
Rarely indicated for hematuria/proteinuria itself, unless related to structural abnormalities like significant hydronephrosis due to obstruction, or large renal masses
Nephrolithiasis may require surgical intervention if conservative measures fail
Management of specific complications like renal artery stenosis might involve intervention.
Supportive Care:
Close monitoring of fluid balance, urine output, blood pressure, and renal function
Nutritional support tailored to the underlying condition
Patient and family education regarding the condition, treatment plan, and follow-up
Psychosocial support for chronic conditions.
Complications
Early Complications:
Acute kidney injury (AKI)
Severe hypertension
Fluid overload (pulmonary edema, ascites)
Electrolyte imbalances
Anemia.
Late Complications:
Chronic kidney disease (CKD)
End-stage renal disease (ESRD)
Growth failure
Hypertension
Increased risk of cardiovascular disease
Recurrence of the primary renal disease.
Prevention Strategies:
Prompt diagnosis and appropriate management of underlying conditions
Strict blood pressure control
Early treatment of UTIs
Adherence to prescribed medications
Regular follow-up with a nephrologist
Lifestyle modifications to promote renal health.
Prognosis
Factors Affecting Prognosis:
The specific underlying diagnosis is the most significant factor
Early and accurate diagnosis
Promptness and adequacy of treatment
Degree of renal impairment at presentation
Presence of hypertension
Genetic factors.
Outcomes:
Prognosis varies widely
Many cases of isolated microscopic hematuria or transient proteinuria resolve spontaneously
However, significant proteinuria or hematuria associated with glomerular disease can lead to chronic kidney disease and ESRD if not managed effectively
Early diagnosis and treatment improve outcomes significantly.
Follow Up:
Regular monitoring of blood pressure, urinalysis (for hematuria and proteinuria), and renal function tests (BUN, creatinine) is essential
Frequency of follow-up depends on the underlying condition, ranging from every few months to annually
Monitoring for complications and growth is crucial in children.
Key Points
Exam Focus:
Differentiating glomerular vs
non-glomerular hematuria (RBC casts, dysmorphic RBCs suggest glomerular)
Understanding the workup for nephrotic syndrome (edema, heavy proteinuria, hypoalbuminemia, hyperlipidemia)
Recognizing post-streptococcal glomerulonephritis presentation and serology
Significance of hypertension in renal disease
Indications for renal biopsy in children.
Clinical Pearls:
Always check BP in a child with hematuria/proteinuria
A single positive dipstick for blood needs confirmation with microscopy
Isolated microscopic hematuria without proteinuria in an otherwise healthy child may not require extensive workup
Always consider UTI as a cause
Urine protein-to-creatinine ratio is the preferred method for quantifying proteinuria in children.
Common Mistakes:
Missing significant hypertension
Inadequate fluid management
Delaying referral to a nephrologist
Incomplete investigation of recurrent or persistent findings
Attributing all hematuria/proteinuria to benign causes without proper evaluation
Inappropriate use of antibiotics for non-infectious causes.