Pediatric Department - Shands Hospital

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Renal Medicine

 

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Hematuria

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Proteinuria
| History | Family History | Physical Exam | Clinical Eval |
Clinical Evaluation
 
a.

A careful urinalysis is essential.

Hematuria and proteinuria is usually indicative of more serious underlying renal disease. Casts are often seen with glomerulonephritis. The exception would be hyaline casts that can be seen with minimal change nephrotic syndrome and are indicative of heavy proteinuria. Proteinuria associated with the loss of substances usually absorbed in the proximal tubule (glucose, phosphorus, amino acids, and potassium) may indicate renal tubular disease and not glomerular disease. Greater than 300mg. /dl. of protein is usually associated with glomerular losses. Thirty to 100 mg/dl. of protein on urine dipstick may be orthostatic or tubular.
b.

If there is a negative history and a physical examination, the most likely cause of asymptomatic proteinuria in an adolescent is orthostatic proteinuria. There are several ways to evaluate for this.

The most convenient in an office setting is to obtain a protein/creatinine ratio on the first voided and a mid morning urine specimen. The ratio should be <0.20 on the first voided urine and <0.50 on the mid morning specimen.

Collecting two 12-hour specimens, one collected while supine and the other while physically active is the most accurate. Again the active urine should have >150 and <500 mg. of protein. The urine specimen collected while supine should have <100 mg. of protein. The total 24- hour specimen should have less than 500mg. total of protein.

If the patient does have orthostatic proteinuria and no other problems (e.g. hypertension, hematuria, acidosis, azotemia) the patient can be followed conservatively. A renal biopsy is not indicated. The patient should be re-evaluated yearly.
c.

A renal function panel is indicated.

Specifically electrolytes, BUN, creatinine, Ca, PO4, total protein, and albumin may help to screen for renal insufficiency or nephritic syndrome.
d.

If the proteinuria appears to be fixed, a renal imaging study should be performed.

An ultrasound of the kidneys is usually adequate. Renal dysplasia/hypoplasia may present as asymptomatic proteinuria.
e.

Serum lipids may be added if nephrotic syndrome is suspected.

They will be elevated in nephrotic syndrome
f. Serum complement levels, ANA, immunoglobulin levels, a sedimentation rate, cryoglobulins, and/or ASO and anti-DNase B titers may be drawn depending upon history and symptoms.
g.

A 24-hour urine collection may be obtained for creatinine clearance and a protein excretion rate, especially if the proteinuria is not thought to be orthostatic.

Protein electrophoresis on the 24-hour urine may be obtained if tubular proteinuria is suspected.
h. A renal biopsy is indicated if glomerular disease is suspected other than minor change nephrotic syndrome in children under 6.
 
| History | Family History | Physical Exam | Clinical Eval |
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