Renal  |  Elective Services




Renal

Elective Services

Referral to Nephrology

Facilitator:

Dr M Fisher, Clinical Director - Renal

Authorised by:

Dr M Fisher, Clinical Director - Renal

Classification:

 

© Waikato DHB June 2009

Please note:
Renal Services are provided through Waikato Hopsital. Referrals must be processed via the BOP Referral Centre.


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

Recurrent Stone Disease


Referral For FSA

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

Immediate referral  

within 24 hours

Urgent referral

within 2-4 weeks

Routine referral

  


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 / l


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

BP Control - treat BP if   > 140/90
Ideal BP   < 130/80
or if U Alb : Creat >100    < 120/75


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

Stage

GFR ml/min/1.73m2  

Consequences

1 - normal

> 90

 

2 - early

60 - 89*

Increased PTH

3 - moderate   

30 - 59

Decreased Ca absorption
Malnutrition
Anaemia - low EPO
Left Ventricular hypertrophy

4 - severe

15 - 29

High phosphates
Acidosis
Potassium may rise

5 - ESRF

< 15

Uraemia

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

Chronic Kidney Disease - New Zealand Management Guidelines

 



Last updated : Tuesday, March 14, 2017
Next review date : Wednesday, March 14,2018


Disclaimer: This site is intended to be flexible and frequently updated. While every effort has been made to ensure accuracy, all information should be verified.