What’s Beyond Creatinine

18
Jun

Have you ever wondered about any of the following in the management of a renal patient?

Why are dogs and cats affected by CKD vomiting and not eating, even under treatment?
Why doesn’t renal diet solve many of the clinical signs related to CKD?
Why are dogs and cats affected by CKD losing weight, even when eating on a regular basis?

If the above sound familiar, join us for a FREE webinar with

Dr Andrea Zatelli DVM, Associate Professor

Department of Veterinary Medicine, University of Bari Italy

Topic: Chronic Kidney Disease (CKD) In Dogs And Cats: What’s Beyond Creatinine

When: Tuesday 30 June 2020, at 7pm CET

During his talk Dr Zatelli will answer the above questions and give useful tips on:

How to rule out metabolic acidosis and electrolyte disorders in CKD
How nutrition and omega-3 fatty acids can help in slowing the progression of CKD
How treatment of metabolic acidosis and electrolyte disorders can improve the quality of life

To register NOW click on the link below:

https://us02web.zoom.us/webinar/register/WN_P0Z6m16qSMirwDLjrzpZmg

About the speaker

Andrea Zatelli graduated with honours from the University of Parma in 1990. He followed several post-graduate trainings in Germany and US. From 1998 to 2012 he’s been working as a practitioner in Italy, with a particular interest toward the nephrology of canine and felines. From 2013 to 2019 he’s been veterinary consultant in Malta. His research involves nephrology and urology of cats and dogs, particularly renal damage consequent to vector-borne disease and diagnosis and treatment of canine glomerulopathies. In 2005 Andrea was awarded from the International Renal Interest Society (IRIS) “in recognition of outstanding fundamental and clinical research performed by an individual in the field of nephrology”. He is founding member of the Canine Leishmaniasis Working Group (www.gruppoleishmania.org). Andrea is author and co-author of publications in peer-reviewed international journals, chapter of books and monographs dedicated to nephrologic and urologic disease of dogs and cats. He is an active speaker at national and international courses and congresses. Currently, Andrea is Associate Professor at the Veterinary Medicine department of the University of Bari (Italy).

Chronic kidney disease (CKD)

Chronic kidney disease (CKD) is a progressive and irreversible process due to the loss of functional renal tissue and represents the most common diagnosis of kidney disease in dogs and cats. Regardless the cause(s) of nephron loss or damage, a kidney disease may be diagnosed through the direct visualization of the renal tissue (renal histopathology) or, most commonly, using markers of renal damage detected by blood (serum creatinine, SDMA) and urine exams. Recommended therapy varies according to the stage of the disease and is finalized to correct abnormalities of CKD such as anemia, metabolic acidosis, hypokalemia, hyperphosphatemia, hypocalcemia other than proteinuria and hypertension when present. Major goals of the medical therapy are prevention and management of complications linked to the impaired renal function, treatment of ongoing pathological conditions and therapy directed to slowing further loss in kidney function.

Diet represents the most recommended therapy in dogs and cats affected by CKD and has a crucial role in the management of nephropatic patients. Modifications in the diet formulation include reducing protein content together with controlling phosphorus level, addition of omega-3 PUFA, neutralizing acid-base balance and increasing the caloric intake. Renal diets have demonstrated efficacy in reducing uremic crisis and death for renal causes in dogs in IRIS stage 3 and 4 and in cats in IRIS stages 2, 3 and 4. Nonetheless patients in the early stages of the disease have no evidence for prescription of a renal diet at the moment, administration of diets with a reduced content in protein is strongly suggested in dogs and cats affected by proteinuria in order to slow the progression of the disease.

Dietary phosphorus restriction plays an important role in limiting retention of this mineral, hyperphosphatemia and consequent secondary hyperparathyroidism in case of the persistency of high level serum phosphorus concentration. Feeding a low phosphorous diet (renal diet) has been shown to increase the survival time in dogs and cats with CKD. When dietary approach is not effective in normalizing serum phosphorus level, phosphate binders should be introduced. Current available binders include calcium- based compounds to be administered mixed with food. Calcium-based drugs could be also helpful in hypocalcemic patients that are well represented in advanced stages of CKD (serum creatinine above 3.5 mg/Dl).

Omega-3 fatty acids (particularly EPA) showed their efficacy in reducing renal related mortality, minimizing renal lesions at histopathology examination, lowering grade of proteinuria, as well as ameliorating renal function in both dogs and cats affected by CKD. Omega-3 PUFA are usually added to renal food, but supplementation with fish oil in capsules is strongly recommended. Suggested dose for supplementation with omega-3 fatty acids (mainly EPA) is 80 mg/kg/day. Products containing Omega-3 PUFA must contain antioxidant compounds (eg. mixed tocopherols) not only in order to guarantee the stability of the product but also to maximize the antioxidative effects of fish oils on renal function.

Metabolic acidosis and electrolyte alterations are usually not represented in the early stages of CKD both in dogs and cats, because the organism is able to compensate mild imbalances; however, when serum creatinine raises up to 3.5 mg/Dl, patients could show low blood pH due to renal causes (low level of serum bicarbonate) and/or alterations like hypokalemia (most of all in cats) and hypocalcemia.

Metabolic acidosis is common in CKD. Persistent metabolic acidosis may cause a variety of adverse clinical effects including anorexia, nausea, vomiting, weakness and lethargy; increased protein catabolism leads to malnutrition, muscle wasting and weight loss that are further consequences of chronic low blood pH. Successful treatment of acid base impairment provides greater survival time: a clinical trial with kPROTECT™, showed how patients with serum creatinine higher than 3.5 mg/Dl have prolonged life-expectancy as a positive response to therapy (median survival time from up to 13 months!).

Main aims of treating metabolic acidosis through alkalizing therapy in patients affected by CKD are: 1) control signs of uremic acidosis, including decreased appetite, lethargy, nausea, vomiting, muscle weakness, and weight loss; 2) minimizing protein catabolism; 3) limiting skeletal damage; 4) preventing severe acidosis and adverse effects on the hemodynamic system (impaired myocardial contractility and enhanced venoconstriction). Moreover, in renal patients, calcium disorders tend to be underdiagnosed as serum total calcium is often discordant with ionized calcium measurement; therefore, total calcium cannot be used to predict levels of ionized calcium. Symptoms of low serum ionized calcium are: muscle weakness, lethargy, arrhythmia. Recent studies demonstrated that over half of the cats and dogs with advanced stages of CKD were hypocalcemic when ionized calcium was detected. Most common treatment in renal patients with hypocalcemia is based on calcium carbonate given orally, at the dosage of 30- 50 mg/kg bw every 12 hours.