Novel Biomarker and Therapeutic Target for Chronic Kidney Disease in Dogs

CKD is commonly encountered in small animal practice, and affects up to 20% of all dogs. It is widely accepted that most dogs with stage II or greater CKD will progress to end-stage renal failure. Early detection of CKD and potential therapeutic targets in early stages of disease remains extremely challenging. Management of CKD in dogs has largely been focused on supportive therapy with very few new therapies available to treat CKD that have shown to improve outcomes.

Several clinical trials in humans indicate that correction of metabolic acidosis with alkali therapy slows progression of CKD even in patients without metabolic acidosis, suggesting that acid-mediated kidney injury might occur even in the setting of normal total bicarbonate in patients with CKD (referred to a subclinical metabolic acidosis). Furthermore, recent studies in humans have shown that CKD patients lower ammonia excretion have a significantly higher risk of developing end stage renal disease, metabolic acidosis or death when compared to CKD patients with higher ammonia excretion. This suggests that quantification of urinary acid excretion, particularly ammonia, maybe a useful guide to identify those with subclinical metabolic acidosis that are at high risk of overt metabolic acidosis and poor outcomes and could benefit from oral alkali therapy.

The primary purpose of this study is to determine if urinary ammonia excretion correlates with renal function, and is associated with the development of metabolic acidosis or long-term clinical outcomes in dogs with chronic kidney disease (CKD).

Participation Requirements:

Inclusion: Dogs diagnosed with IRIS Stage II – IV CKD based on elevated serum creatinine (>1.4 mg/dL) or SDMA (> 18ug/dL) and lack of appropriate urine concentration (two occasions in a stable (< 25% change between measurements) well hydrated patient will be
offered enrollment.  Must be willing to eat study diet (Purina NF dry).

Exclusion: Dog will be excluded from the study if they are less than 1 year of age, have evidence of a lower urinary tract infection, are receiving alkaline therapy or potassium-sparing diuretics, or require hospitalization to manage their CKD.

Owner's Responsibilities:

Owners must be able to bring their pet every 3 for months after study enrollment for blood draw and urine collection for the duration of the study (12 months, 4 study visits total). Each dog enrolled in this study must eat the study diet for the duration of the study (Purina NF, dry).

The laboratory testing performed at each visit is as follows:

1. Study Enrollment Visit: blood and urine collection for a renal biochemistry panel, PCV/TP, urinalysis, urine protein-to-creatinine ratio, and blood pressure measurement.
2. Follow up Study Visits : blood and urine collection for a renal biochemistry panel.

This study will cover the cost of all laboratory testing and provide the study diet (Purina NF, dry)  for study duration (12 months).

1. Dogs must present to the University of Florida Small Animal Hospital
2. No specific geographic residence required
3. Samples can not be sent from owners or clinics