Proteinuria in Canine Cancer Patients

R. Darren Wood, DVM, DVSc, DACVP (Clinical Pathology), University of Guelph

Oncology|March 2019

Sign in to Print/View PDF

In the Literature

Prudic RA, Saba CF, Lourenço BN, Bugbee AC. Prevalence of proteinuria in a canine oncology population. J Small Anim Pract. 2018;59(8):496-500.

FROM THE PAGE …

Loss of protein via the urinary tract can occur secondary to several underlying diseases, including neoplasia. Assessment of the degree of proteinuria in dogs may be helpful for documenting the severity of protein loss, which can help clinicians decide how best to manage the patient.

This study sought to document the point prevalence of proteinuria in a population of dogs with various neoplasms (excluding lower urinary tract neoplasia) and to assess the severity of protein loss. Of the 60 patients enrolled, 51.7% had some degree of proteinuria. Most results were borderline; only 15% of patients exhibited overt proteinuria, and only 2 dogs had a urine protein:creatinine ratio >2.0 (reference value, <0.5).

TABLE

CAUSES OF PROTEINURIA

Prerenal (Overload) Causes Renal Causes Postrenal Causes
Immunoglobulin light chains Glomerular loss Hemorrhage
Hemoglobin Tubular loss Inflammation
Myoglobin   Infection
Strenuous exercise    
Fever    
Seizures    

When evaluating the significance of proteinuria, it is important to review the urine sediment. This is a crucial part of a complete urinalysis and is required for proper interpretation of other variables. Presence of hemorrhage1 or inflammation2 (infectious or noninfectious) in the sample can confound the ability to identify whether presence of protein is due to glomerular leakage or poor tubular reabsorption rather than an active sediment. In this situation, the cause of hematuria and/or pyuria must be identified and addressed, then proteinuria reassessed. If proteinuria persists in the absence of these confounders, it can be assumed that the protein is present due to kidney disease.

In addition, proteinuria must be interpreted in the context of urine specific gravity.2 Although a 1+ dipstick reaction might not be concerning in a well concentrated sample, the same reaction in dilute urine should be taken seriously and further evaluated. Other prerenal causes of mild proteinuria (eg, fever, strenuous exercise) must also be considered.

The results of this study suggest that proteinuria occurs frequently in dogs with cancer, although the clinical significance in most cases may be minimal. Establishing baseline protein loss at cancer diagnosis, with subsequent monitoring for progression during therapy, may be warranted to ensure worsening kidney disease does not impact patient quality of life or management of underlying neoplasia. Other biomarkers of kidney disease should also be taken into consideration.

… TO YOUR PATIENTS

Key pearls to put into practice:

1

Patients identified as proteinuric should have a complete health assessment, including physical examination and diagnostic procedures to rule out underlying neoplasia.

2

Proteinuria should be interpreted in the context of an inactive urine sediment. If hemorrhage or inflammation is present, the amount of protein in the sample will be increased.

 

3

Even if proteinuria appears minimal, patients should be monitored for progression, which could negatively impact patient response to cancer therapy.

References

For global readers, a calculator to convert laboratory values, dosages, and other measurements to SI units can be found here.

Material from Clinician's Brief may not be reproduced, distributed, or used in whole or in part without prior permission of Educational Concepts, LLC. For questions or inquiries please contact us.

Title

field_pronunciation_value

field_data_field_aliases

field_data_field_drug_class


Clinician's Brief provides relevant diagnostic and treatment information for small animal practitioners. It has been ranked the #1 most essential publication by small animal veterinarians for 9 years.*

*2007-2017 PERQ and Essential Media Studies

It's Free & Simple

Subscribe

Delivered to Your Inbox

Newsletter

Join the Conversation

Facebook

Follow us @CliniciansBrief

Twitter

Home

Global Edition

About Us

Employment

Sign In

Capsules

Contact Us

Brief Media

Create Account

© 2018 Educational Concepts, L.L.C. dba Brief Media ™ All Rights Reserved. Privacy Policy (Updated 05/08/2018) Terms of Use (Updated 05/08/2018)