Page 636 - WSAVA2018
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 25-28 September, 2018 | Singapore
G. Segev1
1Koret School of Veterinary Medicine, Israel
most of the clinical manifestations are expected when the animal is in CKD Stage III or above, some of the complications (e.g., hypertension, proteinuria) might be present even in Stage I CKD.
Nutritional management is a cornerstone in the management of CKD. Evidence suggests that consuming a therapeutic kidney diet is associated with lower number of uremic crises and decreased mortality rate compared to patients consuming maintenance diets. Yet, anorexia and weight loss are major factors that influence owners of dogs and cats with CKD to elect euthanasia, and thus many owners and veterinarians elect to feed free choice diets, despite the fact that the latter facilitate uremic crisis and progression. Thus before offering
a therapeutic kidney diet, clinical signs (especially gastrointestinal signs) must be controlled. A variety of commercial diets should be offered, and any transition to a kidney diet must be done gradually and only when clinical signs are controlled. Any attempt to transition a patient to a kidney diet when the animal is presented
to the clinic for the first time, before clinical signs are controlled, is doomed for failure.
Hypertension is common in dogs and cats with CKD
and is associated with rapid progression of the disease. When systemic hypertension is documented or suspected, the risk for end organ damage (i.e., kidney, heart, eye, brain) needs to be evaluated. Typically, hypertension is not considered an emergency unless
it is extreme or when evidence for end organ damage
is apparent. The most commonly used drugs to control hypertension are ACE inhibitors (ACEi) (e.g., enalapril, benazapril), angiotensin receptor blockade (ARBs)
(e.g., telmisartan) and calcium channel blockers (e.g., amlodipine). Caution should be used not to administer ACEi to dehydrated animals, as glomerular filtration rate may drop precipitously if these drugs are introduced before the patient is adequately hydrated or in uremic crisis. In dogs, the IRIS recommendation is to combine ACEi and calcium channel blockers, but in cats calcium channel blockers are usually sufficient to control hypertension. The target blood pressure is systolic blood pressure <160 mmHg.
When present, the initial goal is to identify the origin
of the proteinuria and its cause, as anti-proteinuric therapies should be administered only to animals with renal proteinuria. Common causes (e.g., infectious, inflammatory, neoplastic processes) should be looked for and eliminated if possible. If the initial cause can neither be eliminated nor can be identified, the treatment is symptomatic. Kidney biopsy should be considered as
a diagnostic aid to identify the underlying disease and
  The prevalence of chronic kidney disease (CKD) among dogs and cats is unknown. Estimations range between 0.5-7% in dogs and up to 30% in geriatric cats. Chronic kidney disease is irreversible and progressive in nature even if the inciting cause can be eliminated. Due to the reduced number of nephrons, each remaining nephron is undergoing hypertrophy (and is becoming a “super nephron”), but this compensatory mechanism eventually leads to additional nephron loss.
The current terminology of the disease, as suggested by the International Renal Interest Society (IRIS), is “chronic kidney disease” and it is classified into four stages (see below) to guide therapeutic guidelines and predict the prognosis. Classification into the stage is determined
by plasma creatinine concentration, but is done only when the animal is in steady state. The disease is further classified based on renal proteinuria and blood pressure. Both have been incorporated in the disease staging because there is solid evidence to suggest that proteinuria and hypertension influence the survival of dogs and cats with CKD. The degree of renal proteinuria is determined by the urine protein to creatinine (UPC) ratio. Blood pressure should be determined using appropriate technique and equipment, as stress and anxiety might dramatically influence the blood pressure (“white coat effect”).
The diagnosis of CKD is based on clinical signs, which are often non-specific, and is confirmed by laboratory tests. Serum creatinine, symmetric dimethylarginine (SDMA), urea concentration, urine concentration ability, presence of proteinuria, imaging techniques, blood pressure, and kidney biopsy can all be used to diagnose and classify the disease. Early diagnosis is critical,
 as nephron loss is an irreversible process, thus early intervention slows down the disease progression, and delays onset of clinical signs.
Management of chronic kidney disease
 Treatment goals are to slow down the progression rate and to control the clinical signs and clinicopathologic abnormalities. These include polyuria and polydipsia, anorexia, vomiting, diarrhea, weight loss, anemia, bleeding, protein loss, hypertension, acid base and electrolytes imbalances. Management should be tailored to the specific patient according to its IRIS Stage. While

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