What is the significance of a urine dipstick test positive for hematuria (blood) but negative for leukocytes (white blood cells) in a child?

From the Guidelines

In a child with a urine dipstick positive for blood but not leukocytes, a thorough evaluation is warranted to rule out underlying renal or urological pathology.

Initial Evaluation

Initial management may include:

• A repeat urinalysis to confirm the presence of hematuria 1
• Blood pressure measurement
• Renal function assessment via serum creatinine and electrolyte panel

Further Diagnostic Testing

If the hematuria persists, further diagnostic testing such as:

• Renal ultrasound 1
• Voiding cystourethrogram may be indicated
• Consultation with a pediatric nephrologist is recommended 1

Key Considerations

• The presence of hematuria without leukocytes suggests a possible glomerular source of hematuria, such as glomerulonephritis 1
• A thorough history and physical examination are essential to identify potential causes of hematuria, including family history of renal disease and recent infections 1
• Imaging evaluation, such as ultrasound, may be necessary to assess the size and structure of the kidneys and to rule out underlying renal or urological pathology 1

From the Research

Significance of Urine Dipstick Test Results

The significance of a urine dipstick test positive for hematuria (blood) but negative for leukocytes (white blood cells) in a child can be understood by considering the following points:

• A positive dipstick test for hematuria may indicate the presence of blood in the urine, which can be a sign of a urinary tract infection (UTI), kidney stones, or other kidney problems 2.
• However, a negative dipstick test for leukocytes (white blood cells) may suggest that there is no significant infection or inflammation in the urinary tract 3, 4.
• The sensitivity of dipstick urinalysis for detecting UTI in children is relatively low, ranging from 0.54 to 0.86 for different parameters such as nitrite, blood, and leukocyte esterase 3.
• The presence of hematuria detected by dipstick test can be confirmed by microscopic examination of the urine sediment, which is an important step in diagnosing kidney problems in children 5.
• Urine concentration, as measured by specific gravity, can affect the diagnostic performance of urinalysis for pediatric UTI, with more concentrated urine leading to lower positive likelihood ratios for leukocyte esterase and microscopic pyuria 4.

Possible Causes and Implications

Possible causes of a positive dipstick test for hematuria but negative for leukocytes in a child include:

• Kidney stones or other kidney problems that cause bleeding in the urine but do not involve a significant infection or inflammation 2.
• False positive dipstick test results for hematuria, which can occur in asymptomatic children 5.
• The presence of other underlying conditions, such as chronic kidney disease or genitourinary pathology, which can cause abnormalities in the urine dipstick test results 6.

Diagnostic Considerations

When interpreting urine dipstick test results in children, it is essential to consider the following:

• The results should be confirmed by microscopic examination of the urine sediment to rule out false positives or negatives 5.
• The specific gravity of the urine should be taken into account when interpreting the results of urinalysis for UTI 4.
• Other diagnostic tests, such as urine culture or imaging studies, may be necessary to confirm the diagnosis and guide treatment 3, 2.