RENAL BLOOD TESTSWHAT DO THEY MEAN, WHERE TO GO FOR WHAT TO DO

WHAT WE WILL COVER

• WHO TO SCREEN

• WHAT DO THE RESULTS MEAN

• HOW TO CATEGORISE / CLASSIFY

• MANAGEMENT

• MONITORING

CHRONIC KIDNEY DISEASE (CKD)

• SCREENING FOR CKD – RISK FACTORS

• AGE <60 YEARS

• DIABETES, CARDIOVASCULAR DISEASE, UROLOGICAL DISEASE

• FAMILY HISTORY OF KIDNEY DISEASE

• HYPERTENSION

• SMOKING

• OBESITY

• ETHNICITY – MAORI, PACIFIC, INDO ASIAN (SAME AS CVRA COHORT)

• NEPHROTOXIC DRUGS

• ALBUMIN CREATININE RATIO (ACR), ESTIMATED GLOMERULAR FILTRATION RATE (e-GFR) AND MSU

PROTIENURIAFACTORS AFFECTING URINARY PROTEIN EXCRETION

• INCREASES PROTEIN EXCRETION

• STRENUOUS EXERCISE

• POORLY CONTROLLED DM

• HEART FAILURE

• UTI

• ACUTE FEBRILE ILLNESS

• UNCONTROLLED HYPERTENSION

• HAEMATURIA

• MENSTRUATION

• PREGNANCY

• DECREASES PROTEIN EXCRETION:

• ACEI/ARB

• NSAIDS

MANAGEMENT OF MICROALBUMINURIAMen = ACR >2.5mg/mmol AND

<25mg/mmol*Women = ACR >3.5mg/mmol AND

<35mg/mmol*• LOW SALT DIET

• SMOKING CESSATION

• TARGET BP < 130/80 mmhg

• USE ACEI/ARB

• HBA1C < 55 mmol/mol

• STATIN

• ASPIRIN

* Clinical Pathways can differ from Primary Care Handbook

GOALS OF MANAGEMENT OF CKDMEN = URINE ACR > 25 mg/mmol OR eGFR < 45

ml/min/1.73m2

WOMEN = > 35 mg/mmol OR eGFR < 45 ml/min/1.73m2

• INVESTIGATIONS TO EXCLUDE TREATABLE DISEASE

• REDUCE PROGRESSION OF KIDNEY DISEASE

• REDUCE CVD RISK

• EARLY DETECTION AND MANAGEMENT OF COMPLICATIONS

• AVOIDANCE OF NEPHROTOXIC MEDICATIONS OR VOLUME DEPLETION

• ADJUSTMENT OF MEDICATION DOSES TO LEVELS APPROPRIATE FOR KIDNEY FUNCTION

• APPROPRIATE REFERRAL TO A NEPHROLOGIST WHEN INDICATED* Clinical Pathways can differ from Primary Care Handbook

MONITORING OF CKD• CLINICAL ASSESSMENT:

• BLOOD PRESSURE

• WEIGHT

• LABORATORY ASSESSMENT:

• URINE ACR

• BIOCHEMICAL PROFILE INCLUDING UREA, CREATININE AND ELECTROLYTES

• EGFR

• HBA1C (FOR PEOPLE WITH DIABETES)

• FASTING LIPIDS

• FULL BLOOD COUNT

• CALCIUM AND PHOSPHATE

• PARATHYROID HORMONE (6-12 MONTHLY IF EGFR < 45 ML/MIN/1.73M2)

BLOOD PRESSURE REDUCTION

• CKD CAN CAUSE AND AGGRAVATE HYPERTENSION WHICH CAN CONTRIBUTE TO THE PROGRESSION OF CKD

• REDUCING BLOOD PRESSURE TO BELOW THRESHOLD LEVELS IS ONE OF THE MOST IMPORTANT GOALS IN THE MANAGEMENT OF CKD

• TARGET BP < 140/90 MMHG IF NO PROTEINURIA PRESENT AND LESS AGGRESSIVE TARGET IN ELDERLY

• ACE INHIBITOR OR ARB IS RECOMMENDED AS FIRST LINE THERAPY

• MONITORING OF CREATININE AND POTASSIUM 5-10 DAYS AFTER STARTING AN ACE INHIBITOR OR ARB AND AFTER EACH DOSE INCREMENT

• COMBINED THERAPY OF ACE INHIBITOR AND ARB IS NOT RECOMMENDED

• MAXIMUM TOLERATED DOSES OF ACE INHIBITOR OR ARB ARE RECOMMENDED

• HYPERTENSION MAY BE DIFFICULT TO CONTROL AND MULTIPLE (3-4) MEDICATIONS ARE FREQUENTLY REQUIRED

NOTE: ACE INHIBITORS AND ARBS CAN CAUSE A REVERSIBLE REDUCTION IN GFR WHEN TREATMENT IS INITIATED. IF THE REDUCTION IS LESS THAN 25% AND STABILISES WITHIN TWO MONTHS OF STARTING THERAPY, THE ACE INHIBITOR OR ARB SHOULD BE CONTINUED. IF THE REDUCTION IN GFR EXCEEDS 25% BELOW THE BASELINE VALUE, THE MEDICATION SHOULD BE CEASED AND CONSIDERATION SHOULD BE GIVEN TO REFERRAL TO A NEPHROLOGIST FOR BILATERAL RENAL ARTERY STENOSIS

GLYCAEMIC CONTROL

• TARGET HBA1C < 55 mmol/mol

• FOR PEOPLE WITH DIABETES, BLOOD GLUCOSE CONTROL SIGNIFICANTLY REDUCES THE RISK OF DEVELOPING CKD, AND IN THOSE WITH CKD REDUCES THE RATE OF PROGRESSION

• METFORMIN - MAX DOSE 2 G/DAY WHEN eGFR < 45 AND STOP WHEN eGFR < 30

PLEASE NOTE THE INCREASING RISK OF HYPOGLYCAEMIC EVENTS IN STAGE 4/5 CKD. THERE IS POTENTIAL INCREASED EFFECT OF MEDICINES AS RENAL FUNCTION DETERIORATES SO CONSIDERATION AND CAUTION IS REQUIRED

LIPID LOWERING TREATMENTS

• TC:HDL RATIO < 4

• LIPID-LOWERING TREATMENT SHOULD BE CONSIDERED WHERE APPROPRIATE FOR CVD RISK REDUCTION

• CARE OF INCREASING RISK OF SIDE-EFFECTS, ESPECIALLY RHABDOMYOLYSIS

LIFESTYLE MODIFICATION

• CESSATION OF SMOKING

• WEIGHT REDUCTION

• LOW-SALT DIET

• PHYSICAL ACTIVITY

• MODERATE ALCOHOL CONSUMPTION

ARE SUCCESSFUL IN REDUCING OVERALL CVD RISK

ABSOLUTE CARDIOVASCULAR RISK ASSESSMENT

• PATIENTS WITH MODERATE OR SEVERE CKD (URINE ACR > 25 mg/mmol IN MALES OR > 35 mg/mmol IN FEMALES OR eGFR < 45 mL/min/1.73m2) ARE THE HIGHEST RISK OF A CARDIOVASCULAR EVENT. THEY DO NOT NEED TO BE ASSESSED BY THE CARDIOVASCULAR RISK TOOL

• FOR THESE GROUPS, IDENTIFYING ALL CARDIOVASCULAR RISK FACTORS PRESENT WILL ENABLE INTENSIVE MANAGEMENT BY LIFESTYLE INTERVENTIONS (FOR ALL PATIENTS) AND PHARMACOLOGICAL INTERVENTIONS (WHERE INDICATED)

• CONSIDER COMMENCING ASPIRIN FOR THOSE AT HIGH CVD RISK (ORANGE/RED RISK), THOSE WITH CKD 3B (eGFR < 45) AND/OR PROTEINURIA WITH A PCR > 50 (ACR > 30) AND/OR/ESPECIALLY THOSE WHO HAVE HAD A MYOCARDIAL EVENT. SEE CKD MANAGEMENT IN GENERAL PRACTICE BY KIDNEY HEALTH AUSTRALIA/ANZSN/RACGP

COMMONLY PRESCRIBED DRUGS THAT MAY NEED TO BE REDUCED IN DOSE OR

CEASED IN CKD• ANTIVIRALS

• BENZODIAZEPINES

• COLCHICINE

• DABIGATRAN

• DIGOXIN

• EXENATIDE

• FENOFIBRATE

• GABAPENTIN

• INSULIN

• LITHIUM

• METFORMIN (MAX DOSE 2 G/DAY EGFR 30-45 ML/MIN/1.73 M2 AND STOP IF EGFR < 30 ML/MIN/1.73 M2)

• OPIOID ANALGESICS

• SAXAGLIPTIN

• SITAGLIPTIN

• SOTALOL

• SPIRONOLACTONE

• SULPHONYLUREAS (ALL)

• VILDAGLIPTIN

COMMONLY PRESCRIBED DRUGS THAT CAN ADVERSELY AFFECT KIDNEY

FUNCTION IN CKD:• NSAIDS AND COX-2 INHIBITORS

• BEWARE THE 'TRIPLE WHAMMY' OF NSAID/COX-2 INHIBITOR, ACE INHIBITOR AND DIURETIC (LOW DOSE ASPIRIN IS OKAY) WHICH CAN RESULT IN A POTENTIALLY SERIOUS INTERACTION, ESPECIALLY IF VOLUME-DEPLETED OR CKD IS PRESENT. ENSURE INDIVIDUALS ON BLOOD PRESSURE MEDICATION ARE AWARE OF THE NEED TO DISCUSS APPROPRIATE PAIN RELIEF MEDICATION WITH A GENERAL PRACTITIONER OR PHARMACIST.

• RADIOGRAPHIC CONTRAST AGENTS

• AMINOGLYCOSIDES

• LITHIUM

• CALCINEURIN INHIBITORS

WHAT DO YOU KNOW?

• WHO TO SCREEN

• WHAT DO THE RESULTS MEAN

• HOW TO CATEGORISE / CLASSIFY

• MANAGEMENT

• MONITORING

INDICATIONS FOR REFERRAL TO A NEPHROLOGIST

• REFERRAL TO A SPECIALIST RENAL SERVICE OR NEPHROLOGIST IS RECOMMENDED:

• IF EGFR < 30 ML/MIN/1.73M2

• PERSISTENT SIGNIFICANT ALBUMINURIA (URINE ACR > 70 MG/MMOL)

• A CONSISTENT DECLINE IN EGFR FROM A BASELINE OF < 60 ML/MIN/1.73M2 (A DECLINE > 5 ML/MIN/1.73M2 OVER A SIX MONTH PERIOD WHICH IS CONFIRMED ON AT LEAST THREE SEPARATE READINGS)

• GLOMERULAR HAEMATURIA WITH MACROALBUMINURIA

• CKD AND HYPERTENSION THAT IS DIFFICULT TO GET TO TARGET DESPITE AT LEAST THREE ANTI-HYPERTENSIVE AGENTS.

• ANYONE WITH AN ACUTE PRESENTATION AND SIGNS OF ACUTE NEPHRITIS (OLIGURIA, HAEMATURIA, ACUTE HYPERTENSION AND OEDEMA) SHOULD BE REGARDED AS A MEDICAL EMERGENCY AND SHOULD BE REFERRED WITHOUT DELAY.

• ALSO TAKE INTO ACCOUNT THE INDIVIDUAL'S WISHES AND COMORBIDITIES WHEN CONSIDERING REFERRAL.

• REFERRAL IS NOT NECESSARY IF:

• STABLE EGFR ≥ 30 ML/MIN/1.73M2

• URINE ACR < 30 MG/MMOL (WITH NO HAEMATURIA)

• CONTROLLED BLOOD PRESSURE.

• THE DECISION TO REFER OR NOT MUST ALWAYS BE INDIVIDUALISED. PARTICULARLY IN YOUNGER INDIVIDUALS THE INDICATIONS FOR REFERRAL MAY BE LESS STRINGENT.