Proteinuria (Excessive Protein in Urine) in Dogs
Diagnosis In-depth When a positive reaction for protein is detected on a routine urinalysis, the urine sediment should be evaluated If pyuria (white blood cells in urine) is present then culture the urine to determine which type of bacteria is present If blood is present in the urine look for causes of hemorrhage If positive for blood but no intact red cells are seen consider hemolysis (red blood cell destruction). A positive blood test can also indicate hemoglobin or myoglobin in the urine If casts of kidney tubules are seen, a disease of the kidney should be considered Perform a urine protein/creatinine (U P/C) ratio. Measures the amount of protein and creatinine in a single sample. The U P/C of a single random urine sample from dogs with normal and abnormal glomerular function correlates with a 24 hour collection determination. A ratio greater than 1 is considered abnormal. A 24 hour total urine protein quantification can also be performed by collecting all the animal’s urine over a 24 hour period. In general, urine protein excretion values less than 30 mg/kg/day can be considered normal for cats and dogs. Once proteinuria is confirmed obtain a complete blood count (CBC) and serum biochemistry profile If the blood albumin level is decreased suspect glomerular disease Blood pressure determination is important to identify systemic hypertension (high blood pressure) Clotting profile and antithrombin III levels are performed to determine if the pet is at risk for bleeding problems or at an excessive risk for developing a thromboembolus (blood clot) Kidney biopsy ultimately is needed to identify glomerulonephritis from amyloidosis
For more information, please read glomerulonephritis.
The treatment of proteinuria depends on the the underlying cause.