What does a positive bilirubin and protein on urine dipstick indicate in a child?

From the Guidelines

A positive bilirubin and protein on urine dipstick in a child indicates a potential kidney issue, such as glomerulonephritis or nephrotic syndrome.

Key Findings

• The presence of proteinuria (>2+ by dipstick) and hematuria suggests a glomerular source of hematuria [ 1 ].
• A urine dipstick test showing ≥2+ protein and positive for red blood cell casts or white blood cell casts indicates abnormal proteinuria or urine sediment [ 1 ].
• In children, persistent significant proteinuria (grade 1+ by urine dipstick analysis or protein-to-creatinine ratio 0.2 for 3 specimens) may indicate the need for referral to a pediatric nephrologist and potentially percutaneous renal biopsy [ 1 ].
• The management of idiopathic childhood nephrotic syndrome involves corticosteroid therapy and potentially steroid-sparing agents [ 1 ].

Clinical Implications

• A thorough clinical evaluation, including history and physical examination, is essential in determining the cause of hematuria and proteinuria in children [ 1 ].
• Imaging studies, such as ultrasound, may be necessary to assess the size and position of the kidneys and to screen for structural lesions [ 1 ].
• Renal biopsy may be necessary to determine the histopathological diagnosis and guide prognosis and therapy [ 1 ].

From the Research

Urine Dipstick Test Results

A positive bilirubin and protein on a urine dipstick test in a child may indicate several things:

• The presence of bilirubin in the urine can be a sign of liver disease or a bile duct obstruction 2
• Proteinuria, or the presence of protein in the urine, can be a sign of kidney disease or damage 3, 4
• However, it's also important to note that urine dipstick tests can produce false positive results, especially in the presence of other abnormalities such as high specific gravity, hematuria, or ascorbic acid interference 4, 5

Factors Affecting Test Results

Several factors can affect the accuracy of urine dipstick test results, including:

• High specific gravity and hematuria, which can lead to false positive results for proteinuria 4
• Ascorbic acid interference, which can cause false negative results for glucose, hemoglobin, nitrite, and bilirubin 5
• The presence of other abnormalities, such as leukocyte esterase, ketonuria, or urobilinogen, which can also affect test results 4

Clinical Significance

The clinical significance of a positive bilirubin and protein on a urine dipstick test in a child depends on the individual case and the presence of other symptoms or abnormalities:

• If the test results are unexpected, it's possible that they may not be clinically significant 2
• However, if the test results are confirmed by further testing, such as albumin-to-creatinine ratio (ACR) testing, they may indicate the presence of an underlying medical condition 3, 4