Introduction

This guideline relates to single kidney in paediatric patients (<18 years)

Approximately 1/750 children will have a congenital absence of one kidney. The majority will have a kidney showing compensatory hypertrophy, and normal cortico-medullary differentiation with overall normal renal function. However, in the long term, this condition may cause hyperfiltration injury resulting in increased risk of hypertension and proteinuria.

When to refer

• All referrals for single kidney will be considered by our team.
• Referrals triaged within 3-6 months:
  • Patients <12 months of age with single kidney
  • Patients >12 months with a single kidney + abnormal appearance on renal ultrasound (loss of corticomedullary differentiation, evidence of scarring, cysts, dilatation, lack of compensatory hypertrophy, and/or lack of renal growth on 2 consecutive ultrasounds more than 6 months apart)
  • Associated hypertension or proteinuria
• Referrals triaged after 12 months:
  • Patients >12 months of age with normal appearing single kidney showing compensatory hypertrophy

Wait time for appointments 

Specialist Clinic wait times

(Please note, non-urgent referrals for patients over the age of 16 may be declined if it is likely they will not be seen before their 18^th birthday.)

Services available closer to home

Alternative paediatric nephrology services available in Victoria:

• Monash Children's Hospital

Referral criteria/required information

Starred items (*) are mandatory.

• *Details of clinical concern requiring nephrologist input, including duration of symptoms and details of all treatments offered to date.
• *Current HEIGHT and weight
  • *patient height is essential to interpret the appropriateness of the renal length
• *Observations including BP
  • Ensure appropriately sized blood pressure cuff is utilised
  • Ensure blood pressure is compared to percentiles based on height, age and sex of child
• Blood tests (not required in a normal-looking single kidney):
  • Electrolytes, urea, creatinine (EUC)
  • Calcium, magnesium, phosphate, albumin
• Urine tests:
  • Early morning urine (i.e. the urine passed when the child first gets up for the day) for total protein: creatinine ratio (NOT an albumin:creatinine ratio)
• *Renal ultrasound report – REQUIRED (see below)
• *The referral must detail that the referring clinician has arranged a repeat renal ultrasound to be performed according to the following guidance.
  • <3 months of age at referral – repeat in 3 months
  • 3-12 months of age at referral – repeat in 6 months
  • 1-2 years of age at referral – repeat in 12 months
  • >2 years of age – not required (RCH will arrange at first appointment)

All future ultrasounds are to be copied to Department of Nephrology, Royal Children’s Hospital, Fax (03) 9345 5054 or email: kidney@rch.org.au, but must be followed up by the requesting doctor if specialist review is delayed.

Failure to include reports of pathology and radiology investigations will result in the referral being returned to the referring doctor for resubmission.

Referrals from public hospitals MUST INCLUDE the name and contact details of a consultant supervising paediatrician/neonatologist and GP. The patient remains in the care of the referrer until such time that they are seen in the Kidney Clinic.

How to refer

Specialist Clinics referral

Please complete the above and submit via:

• Facsimile (03) 9345 5034 or

• Email screferrals@rch.org.au

Suggested pre-referral management

• So long as the contralateral kidney shows compensatory hypertrophy and normal normal cortico-medullary differentiation, no dilatation, and the child is normotensive and otherwise healthy, specialist review is non-urgent.
• Families should be counselled at the point of referral regarding:
  • symptoms and signs of urinary tract infections (UTI) as early treatment leads to improved outcomes
  • avoiding dehydration
  • NSAIDs are not contraindicated but preferably avoided when possible
  • If participating in high impact sports, consider a referral to OT/Orthotic for kidney guards

Information for families

Your child’s referral will be triaged based on the information received in the referral. Your referrer will continue to monitor and manage your child’s care prior to and after your consultation. If there is a change in the clinical situation, a new referral explaining the need for re-triage of the referral is required. If you are seen elsewhere, please cancel your appointment with our service so that we can provide service to another child on our wait list.

Resources and links

• Life with a single kidney – Kidney Health Australia
• Renal agenesis – InfoKids

Acknowledgements

The development of this guideline was coordinated by the Department of Nephrology. Guideline reviewed in June 2026.