Referrals and Advice

Indications For Referral

Acute Renal Failure (ARF) :

Rise in sCreatinine by >50% in hours / days
- when an elevated sCreatinine is noted for the first time the serum creatinine and urinalysis must be repeated immediately

Chronic Kidney Disease  (CKD):

• eGFR < 60ml/min/1.73m2 with progressive decline in function or complications of CKD
• eGFR < 30ml/min/1.73m2

Hypertension:

• Not controlled on three or more antihypertensives
• More than 20% rise in sCreatinine after starting ACE I /ARB

Proteinuria:

• Urine protein : creatinine ratio > 100mg / mmol  or
• Urine albumin: creatinine ratio >100mg / mmol (equivalent to > 1gm / 24hours )
• Haematuria associated with proteinuria - urine albumin : creatinine ratio > 30mg / mmol
• or isolated haematuria with no underlying urological cause

Referral For FSA

Category definitions:

These are recommended guidelines for DHB specialists prioritizing referrals from primary care.

Immediate and urgent cases must be discussed with the Specialist or registrar in order to get appropriate prioritization and then a referral letter sent, faxed or emailed.  The times to assessment may vary depending on the size and staffing of the hospital.

Immediate Referral:

• Acute Renal Failure - > 1.5 fold increase in sCreat over hrs -  5 days
• Newly detected ESRF -  GFR < 15 ml / min
• Malignant hypertension 
• Hyperkalaemia  > 7 mmol / 

Urgent:

• Newly detected CKD   4 GFR 15 - 29ml/min
• Nephrotic syndrome  - proteinuria > 3gm / 24 hours
• Multisystem disease  e.g.SLE, myeloma  with kidney involvement
• Hyperkalaemia  6 - 7 mmol / l

Routine referral:

• Stable CKD 4
• CKD 3 with progressive fall in eGFR - 20% rise in sCreat (or 15% fall in GFR) over 12 months 
• Difficult to control hypertension
• 20% rise in sCreat (or 15% fall in GFR) within two weeks of starting ACE I
  or ARBs (ACE I / ARBs should be discontinued)
• Proteinuria > 1gm / 24 hours (u protein : creat >100mg/ mmol
  or u alb:creat >100mg / mmol ) - without known diabetic nephropathy
• Haematuria with proteinuria
• Isolated haematuria once  urological causes excluded
• Recurrent Stone Disease.

Information Required for Referral:

• Relevant medical history
• Medications
• BP
• FBC, s creatinine, eGFR, Na, K, urea, Alb, Ca, Phos, gluc (HbA1c) Urine microscopy and urine protein : creatinine ratio or albumin:creatinine ratio(urine dipsticks will not detect microalbuminuria)
• Renal Ultrasound (if available)

Assessment of Kidney Function:

Kidney function should be assessed by Serum creatinine, reported in umol/l and the estimated glomerular filtration rate (eGFR) - reported routinely using the MDRD formula in  eGFR may be unreliable or is yet to be validated in ml/min/1.73m2

• those under 18 years
• where the eGFR is > 60ml/min/1.73m2 
• pregnancy
• rapidly changing kidney function (do not use in ARF)
• extremes of muscle mass  e.g. amputees, high and low BMI
• certain populations - Asian, Polynesian

Where drug dosing according to renal function is important the eGFR needs to be corrected for actual BSA (i.e. eGFR x actual BSA divided by 1.73)

Age adjusted reference ranges not recommended - Complications of reduced eGFR are the same at any age

Urinalysis:

• Urine dipstick for blood and protein.
• If positive for blood, check MSU for culture and urine microscopy.
• If positive for protein, check urinary protein: creat or alb:creat ratio.  Urine dipsticks will not detect other proteins such as light chains in myeloma.
• Albuminuria is a marker of risk of progression of kidney disease and increased cardiovascular risk.

Identification of Patients with CKD:

CKD is defined as an eGFR of > 60ml/min/1.73m2 associated with proteinuria with or without haematuria or an eGFR of < 60ml/min/1.73m2  for more than three months.

Early detection of CKD is important to prevent further injury and progressive loss of renal function.

High risk populations, i.e. those with:

• Diabetes
• Hypertension  - especially those on ACE I / ARBs
• Coronary, cerebral or peripheral vascular disease
• Structural kidney problems  - reflux,  ADPKD
• Multisystem diseases - SLE, rheumatoid arthritis, myeloma, vasculitis
• Family History of kidney disease
• Recurrent stone formers

should have annual tests of kidney function.

Management of patients with CKD:

eGFR >60ml/min/1.73m2

• Identify those at risk for disease progression:
• Proteinuria > 1gm / 24 hours
• Proteinuria and haematuria

Polycystic Kidney Disease:

Refer if diagnosis unclear

Assessment and management of cardiovascular risk factors
BP control as below

Monitor Creatinine and Potassium - at least annually

eGFR 30 - 59 ml/min/1.73m2

Monitor FBC, Electrolytes, Creatinine, eGFR, Calcium, Phosphate, PTH, lipids, BP - minimum of 6 monthly

Request Renal Ultrasound

Refer if progressive rise in serum creatinine

First line treatment - ACE I
     check creatinine and K within 5 days
     stop ACE I and refer if > 20 % rise in creatinine.

Treat hypercholesterolaemia
Advise on weight loss and smoking cessation
If diabetic ensure blood sugar control is optimised

Anaemia exclude other cause
     refer if Hb < 100gm / l

Calcium / Phosphate   refer if outside normal range

Review drugs and drug doses

eGFR 15 - 29 ml/min/1.73m2   - as above plus

Referral  for Nephrology opinion is indicated for consideration of Renal Replacement Therapy and :

Treatment of  anaemia - Erythropoietin and i.v. Iron

Management of Ca, Phos, PTH

Management CVS risk factors

Dietary advice - Na, K, Phos, Protein 

Pre - dialysis education
- preparation for dialysis / transplantation
- for conservative treatment

eGFR < 15ml/min/1.73m2

Immediate referral
 
Note: Not all patients are suitable for  renal replacement therapy especially those who:

• are uncooperative / refusing treatment
• have significant co-morbidities with no prospect of improvement in QoL / life expectancy.

Appendix

Classification of CKD

* associated with urinary abnormalities, especially proteinuria, or structural abnormalities; Polycystic Kidneys, reflux nephropathy.

• Chronic Kidney Disease - New Zealand Management Guidelines