Chronic Renal Failure in Chronic Renal Failure in Cats: Cats: Can we Halt the Decline?Can we Halt the Decline?

Martha CannonMartha CannonBA VetMB DSAM(Fel)BA VetMB DSAM(Fel)

RCVS Specialist in Feline MedicineRCVS Specialist in Feline Medicine

Oxford Cat Clinic01865 243000

Chronic Kidney DiseaseChronic Kidney Disease

Chronic Kidney DiseaseChronic Kidney Disease

Consequences of Kidney DiseaseConsequences of Kidney DiseasePolyuria / polydipsia Polyuria / polydipsia dehydration dehydrationNausea Nausea vomiting / inappetence vomiting / inappetenceRenal secondary hyperparathyroidism (Renal secondary hyperparathyroidism ( Phos) Phos)ProteinuriaProteinuriaHypertensionHypertensionHypokalaemiaHypokalaemiaUrinary tract infectionsUrinary tract infectionsAnaemiaAnaemia

IRIS Staging SystemIRIS Staging System

CreatinineCreatinine

Serum PhosphateSerum Phosphate

ProteinuriaProteinuria

Blood PressureBlood Pressure

CRF: IRIS Staging SystemCRF: IRIS Staging System

Creatinine: After treating dehydrationCreatinine: After treating dehydrationStage 1: Non-azotaemicStage 1: Non-azotaemic> 33% nephrons> 33% nephrons

Stage 2: Creat 140 – 250Stage 2: Creat 140 – 25033-25% nephrons33-25% nephrons

Stage 3: Creat 251 – 439Stage 3: Creat 251 – 43925-10% nephrons25-10% nephrons

Stage 4: Creat > 440 Stage 4: Creat > 440 <10% nephrons<10% nephrons

Aims of TreatmentAims of Treatment

Stage 2: Stage 2: Creatinine 140-250 Creatinine 140-250 μμmol/lmol/l

Aim: (Reverse the cause) Prevent progressionAim: (Reverse the cause) Prevent progression(Serum phosphate, urine protein and UTI’s, blood pressure)(Serum phosphate, urine protein and UTI’s, blood pressure)

Stage 3: Stage 3: Creatinine 251-439 Creatinine 251-439 μμmol/lmol/l

Aim: Prevent progression and manage azotaemia to Aim: Prevent progression and manage azotaemia to improve quality of lifeimprove quality of life

Stage 4: Stage 4: Creatinine >440 Creatinine >440 μμmol/lmol/l

Treatment mostly aimed at managing azotaemiaTreatment mostly aimed at managing azotaemia

IRIS Staging SystemIRIS Staging System

CreatinineCreatinine

Serum PhosphateSerum Phosphate

ProteinuriaProteinuria

Blood PressureBlood Pressure

HyperphosphataemiaHyperphosphataemia

IRIS recommendations:IRIS recommendations:Stage I + II:Stage I + II: 0.81-1.45 mmol/l0.81-1.45 mmol/l

Stage III:Stage III: 0.81-1.61 mmol/l0.81-1.61 mmol/l

Stage IV:Stage IV: 0.81-1.94 mmol/l0.81-1.94 mmol/l

Recommended levels are Recommended levels are well within well within laboratory reference rangeslaboratory reference ranges

HyperphosphataemiaHyperphosphataemia

Reduced phosphate diet is most Reduced phosphate diet is most effective treatmenteffective treatmentAdditional advantages of prescription Additional advantages of prescription dietsdietsReduced azotaemia, KReduced azotaemia, K+ + supplement, Vit B supplement, Vit B supplement, soluble fibre, ? Omega-3 FAssupplement, soluble fibre, ? Omega-3 FAs

HyperphosphataemiaHyperphosphataemia

Protein Restricted DietProtein Restricted DietReduces uraemiaReduces uraemiaImproves well-being, appetite, activityImproves well-being, appetite, activity

Reduces dietary phosphate intakeReduces dietary phosphate intake

Controls hyperphosphataemiaControls hyperphosphataemiaProlongs life-spanProlongs life-spanMedian 800 days vs 264 days

HyperphosphataemiaHyperphosphataemia

Reduced phosphate diet is most Reduced phosphate diet is most effective way to control phosphateeffective way to control phosphate

Additional advantages of prescription diets

Reduced azotaemia, K+

supplement, Vit B supplement, Soluble fibre, Omega-3 FAs ... ...

Chronic Kidney DiseaseChronic Kidney Disease

Nutritional ManagementNutritional ManagementEnsure adequate intakeEnsure adequate intakeDelay introduction until cat feels wellDelay introduction until cat feels wellLearned food aversion

Canned dietsCanned dietsEnergy from fat cf carbohydrate

Increased fluid intake

Phosphate BindersPhosphate Binders

Hyperphosphataemia Hyperphosphataemia despite dietary controldespite dietary controlAllow 6-8 weeks for Allow 6-8 weeks for control of phosphatecontrol of phosphate

Gradual introduction of Gradual introduction of binder if phosphate binder if phosphate remains highremains high

HyperphosphataemiaHyperphosphataemia

Intestinal Phosphate BindersIntestinal Phosphate Binders~10% reduction in serum phosphate~10% reduction in serum phosphateGive Give mixed with foodmixed with food

Divide between Divide between all mealsall meals

Introduce gradually and titrate to effectIntroduce gradually and titrate to effect

Monitor serum calcium when introducing bindersMonitor serum calcium when introducing binders

IRIS Staging SystemIRIS Staging System

CreatinineCreatinine

Serum PhosphateSerum Phosphate

ProteinuriaProteinuria

Blood PressureBlood Pressure

IRIS Staging SystemIRIS Staging System

Rule out UTI / FLUTDRule out UTI / FLUTDMust check urine sediment or cultureMust check urine sediment or cultureAsymptomatic bacterial urinary infections Asymptomatic bacterial urinary infections are common in cats with CKD,are common in cats with CKD,

especially female catsespecially female cats

IRIS Staging SystemIRIS Staging System

Proteinuria with no active sedimentProteinuria with no active sedimentUP:C > 0.4 = proteinuricUP:C > 0.4 = proteinuricTreat with an ACE inhibitor

UP:C < 0.2 = non-proteinuricUP:C < 0.2 = non-proteinuricNo treatment required

UP:C 0.2-0.4 =borderlineUP:C 0.2-0.4 =borderlineMonitor / treat

Chronic Renal FailureChronic Renal Failure

Urinary Tract InfectionsUrinary Tract InfectionsAsymptomatic UTI’sAsymptomatic UTI’s

Female catsFemale cats

Low urine SGLow urine SG

? Occult pyelonephritis? Occult pyelonephritis

Risk of ascending infection Risk of ascending infection renal damage renal damage

Chronic Renal FailureChronic Renal Failure

Urinary Tract InfectionsUrinary Tract InfectionsTreatmentTreatment4-6 weeks of antibiotic4-6 weeks of antibioticBactericidal antibiotic

Repeat urine sediment +/- cultureRepeat urine sediment +/- cultureBefore end of antibiotics

10 days after ceasing antibiotics

IRIS Staging SystemIRIS Staging System

CreatinineCreatinine

Serum PhosphateSerum Phosphate

ProteinuriaProteinuria

Blood PressureBlood Pressure

CRF: IRIS Staging SystemCRF: IRIS Staging System

HypertensionHypertensionCommon Common

consequence of CRFconsequence of CRF

Contributes to Contributes to progression of CRFprogression of CRF

CRF: IRIS Staging SystemCRF: IRIS Staging System

Blood PressureBlood Pressure

““Risk of end organ damage”Risk of end organ damage”< 150 mmHg = Minimal risk< 150 mmHg = Minimal risk

150-160 mmHg = Low risk150-160 mmHg = Low risk

160-180 mmHg = Moderate risk160-180 mmHg = Moderate risk

> 180 mmHg = High risk> 180 mmHg = High risk

www.iris-renal.comwww.iris-renal.com

CRF: Blood PressureCRF: Blood Pressure

For cats with CRFFor cats with CRFMaintain BP below 170 mmHgMaintain BP below 170 mmHg

Amlodipine: 0.625 – 1.25 mg per cat per Amlodipine: 0.625 – 1.25 mg per cat per dayday

1/8 or 1/4 of a tablet once daily

Adjunctive TreatmentAdjunctive TreatmentBenazepril

Chronic Renal Failure in Chronic Renal Failure in Cats: Cats: Can we Halt the Decline?Can we Halt the Decline?

Martha CannonMartha CannonBA VetMB DSAM(Fel)BA VetMB DSAM(Fel)

RCVS Specialist in Feline MedicineRCVS Specialist in Feline Medicine

Oxford Cat Clinic01865 243000