Hematuria and kidney stones
Assess a child with red urine or blood on urinalysis step by step, refer correctly to a nephrologist or urologist, and look for the cause in a child with a stone.
Step 1 of 11
Objectives
After this course you will be able to
- Confirm hematuria with microscopy and recognize pseudohematuria.
- Distinguish glomerular from nonglomerular hematuria.
- Know the initial workup algorithm and what is not needed.
- Explain why a stone in a child requires a metabolic evaluation.
- Know the treatment options according to stone size and location.
Key message: not all red urine is blood, and no stone is without a cause. After the first stone in a child, a metabolic evaluation should be performed.
Basics
Confirming hematuria
- Microscopic hematuria: ≥5 red blood cells per high-power field on microscopy in repeated samples.
- Gross hematuria: blood visible to the eye.
- The dipstick also reacts to hemoglobin and myoglobin: a positive dipstick must be confirmed by microscopy.
- Red urine without red blood cells: foods (beets, blackberries), medications (rifampin), urate crystals in an infant, myoglobinuria, hemoglobinuria.
A small number of red blood cells in a single sample is common. When isolated, asymptomatic microscopic hematuria is found, the urinalysis is repeated 2–3 times over several weeks.
Basics
Glomerular or nonglomerular?
| Feature | Glomerular | Nonglomerular |
|---|---|---|
| Color | Brown, "cola", tea-colored | Red, pink |
| Clots | Absent | May be present |
| Red blood cells | Dysmorphic, red cell casts | Normal shape |
| Proteinuria | Often present | Usually absent or mild |
| Other | Edema, hypertension, oliguria | Pain, dysuria, trauma, terminal hematuria |
| Referral | Pediatric nephrologist | Pediatric urologist |
Basics
Causes
Nonglomerular: urinary tract infection, hypercalciuria, stones, trauma (especially after a minor blow to a hydronephrotic kidney), meatal stenosis, urethrorrhagia in adolescent boys, nutcracker phenomenon, and rarely tumors (Wilms tumor) and vascular anomalies.
Glomerular: poststreptococcal glomerulonephritis (1–3 weeks after a throat or skin infection), IgA nephropathy (at the same time as an infection or 1–2 days later), thin basement membrane disease, Alport syndrome, Henoch-Schönlein purpura nephritis.
A tumor is a rare cause of isolated hematuria in children. Hematuria together with an abdominal mass, however, requires urgent ultrasound.
Diagnosis
Initial workup
- Urinalysis with microscopy; urine culture.
- Urine protein/creatinine and calcium/creatinine ratios (on the first morning void).
- Blood pressure, edema, abdominal examination.
- Family history: hematuria, kidney failure, hearing loss, stones.
- Kidney and bladder ultrasound.
- If glomerular disease is suspected: creatinine, C3, other nephrology tests as needed, and a nephrology consultation.
The normal calcium/creatinine ratio decreases with age: in children older than 7 years, a result above 0.2 mg/mg (about 0.6 mmol/mmol) suggests hypercalciuria. In younger children, age-specific reference values are used.
Cystoscopy is not a routine study for hematuria in children. Hematuria with acute pain, fever, oliguria, edema or hypertension, however, requires same-day assessment.
Diagnosis
Stones in children: clinical signs and imaging
- risingincidence in children
- oftena metabolic cause is found
- Ultrasoundfirst-line imaging
- <5 mmoften pass spontaneously
- In older children: typical renal colic, nausea, hematuria.
- Young children often lack typical pain: irritability, vomiting, UTI, or an incidental ultrasound finding.
- Ultrasound is the first-line imaging. If ultrasound is insufficient, low-dose noncontrast CT.
- Plain X-ray can be useful for following radiopaque stones.
Diagnosis
Metabolic evaluation
In children, a stone is often caused by a metabolic disorder, an anatomic anomaly or infection. After the first stone, every child should have:
- Chemical analysis of the stone (a passed stone should be saved).
- Serum calcium, phosphorus, magnesium, uric acid, creatinine, electrolytes; PTH if calcium is elevated.
- 24-hour urine for calcium, oxalate, citrate, uric acid, cystine, magnesium, creatinine and volume (if not feasible, spot ratios on a morning sample).
- Urine pH, urinalysis and culture.
The most common metabolic causes in children are hypercalciuria and hypocitraturia. Cystinuria, primary hyperoxaluria and distal renal tubular acidosis are rare but important diagnoses.
Treatment
Acute phase
- Analgesia (nonsteroidal anti-inflammatory drugs), adequate fluids.
- Observation for small ureteral stones; in some cases an alpha-blocker to facilitate stone passage (off-label in children).
- Catch the passed stone with a strainer and send it for analysis.
Fever with an obstructed kidney is an emergency: the kidney is first drained with a stent or nephrostomy, the infection is treated, and the stone is removed later.
Treatment
Stone removal
| Situation | Typical choice |
|---|---|
| Kidney stone up to 2 cm | Shock wave lithotripsy (ESWL) or retrograde intrarenal surgery (RIRS) |
| Kidney stone larger than 2 cm or complex | Percutaneous nephrolithotomy (mini-PCNL) |
| Ureteral stone that does not pass | Ureteroscopy and laser lithotripsy |
| Stone with an anatomic anomaly | Together with correction of the cause (for example, pyeloplasty) |
Open stone surgery is now almost never performed in children.
Treatment
Preventing recurrence
- Plenty of fluids: urine should be light in color; daily volume is set by age and weight.
- Reduce salt: processed foods, chips, sausage.
- Do not restrict calcium: normal dairy intake; if calcium is reduced, oxalate absorption increases.
- Citrate supplements for hypocitraturia; a thiazide for hypercalciuria when needed.
- Rare diseases such as cystinuria and hyperoxaluria require specific treatment together with a nephrologist.
The pediatrician's role: confirm hematuria with microscopy, refer to a nephrologist when there are glomerular signs, never leave a child with a stone without a metabolic evaluation, and treat fever with obstruction as an emergency.
Quiz
Quiz: Hematuria and stones
Test yourself: choose one answer.
-
A 6-year-old has a dipstick positive for blood, no red blood cells on microscopy, and ate a lot of beets the day before. What is this?
Hematuria is confirmed by microscopy. If there are no red blood cells, the color is due to food, medication or hemoglobin/myoglobin.
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Two weeks after a sore throat, an 8-year-old has "cola-colored" urine, periorbital edema and high blood pressure. To whom should the child be referred?
This is the typical picture of glomerular hematuria (suspected poststreptococcal glomerulonephritis). With edema and hypertension, urgent nephrology assessment is needed.
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A first kidney stone has been found in a 10-year-old. Which step is mandatory?
Stones in children are often due to a metabolic cause. After the first stone, a 24-hour urine collection, blood tests and stone analysis are performed.
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What is the first-line imaging study for a suspected stone in a child?
Ultrasound involves no radiation and is sufficient in most cases. Low-dose noncontrast CT is done when needed.
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A child with a ureteral stone and obstruction has a fever of 39 °C. What is the most appropriate approach?
An obstructed, infected kidney is an emergency. Drainage and antibiotics come first, and the stone is removed after the infection has resolved.
Course completed
Related articles for parents
Sources
- EAU Guidelines on Paediatric Urology, 2025: Urolithiasis.
- EAU Guidelines on Urolithiasis, 2025: Paediatric stones.
- Viteri B, Reid-Adam J. Hematuria and proteinuria in children. Pediatr Rev. 2018;39(12):573–587.
This material is intended for medical professionals and is based on current clinical guidelines. Decisions about an individual patient are made by the treating doctor.