Skip to content
How It Works
Explore
Resources Ask a Question
Who It's For
Patients Caregivers Providers
Log In Ask a Question
PubMed This is a summary of 16 peer-reviewed journal articles Updated
Pediatric Nephrology · Multicystic Dysplastic Kidney

The Care Journey: Monitoring Your Child's Kidneys

At a Glance

The standard of care for Multicystic Dysplastic Kidney (MCDK) is conservative management rather than surgery. Doctors use regular ultrasounds to watch the cystic kidney shrink and ensure the healthy kidney grows to compensate. Protecting the remaining healthy kidney from UTIs is critical.

Managing a child with Multicystic Dysplastic Kidney (MCDK) has changed significantly over the last few decades. In the past, doctors often removed the affected kidney through surgery. Today, because we know how well most children do with this condition, the standard of care is a “watch and wait” approach called conservative management [1][2][3].

The Shift Away from Surgery

You may read older information or hear from others that the cystic kidney should be removed (nephrectomy). However, modern medical research shows that prophylactic (preventative) surgery is almost never necessary for the following reasons:

  • Involution: The affected kidney naturally shrinks and often vanishes (involutes) over time [4][5].
  • Low Risk: The risk of this kidney causing high blood pressure or other severe complications is low [1][3].
  • Focus on the Healthy Kidney: Surgery does not improve the function of the remaining healthy kidney, so monitoring is a safer, non-invasive path [1][6]. Surgery is generally reserved only for extremely rare cases where the cysts grow large enough to cause breathing or feeding issues (mass effect), or if there is severe, untreatable hypertension [3].

Your Monitoring Roadmap: Serial Ultrasounds

The primary tool for monitoring your child is the renal ultrasound. This painless scan allows doctors to track two critical developments simultaneously:

  1. Involution of the MCDK: Seeing the cysts shrink and the abnormal kidney get smaller [7][8].
  2. Compensatory Hypertrophy: Ensuring the “good” kidney is growing larger than average to compensate for the non-working one [7][9]. Most children show this healthy growth by age 3.

While your doctor will provide a specific schedule, it often involves a scan shortly after birth, followed by regular scans during the first few years of life [10][11].

Specialized Testing: Only When Necessary

In the past, every baby with MCDK was given invasive tests. Now, doctors use a more selective approach to avoid unnecessary procedures.

Voiding Cystourethrogram (VCUG)

A VCUG is an X-ray test that checks for vesicoureteral reflux (VUR), which is when urine flows backward from the bladder into the healthy kidney. This test is no longer routine for all asymptomatic babies with MCDK [12][13][14]. It is typically only ordered if:

  • The healthy kidney looks abnormal or “dilated” on an ultrasound [12][10].
  • Your child develops signs of a urinary tract infection (UTI) [14][13].

Renal Scintigraphy

These are nuclear medicine scans that look at kidney function. Like the VCUG, these are rarely used routinely because a high-quality ultrasound is usually enough to confirm that the MCDK kidney has no function and that the other kidney is healthy [10][14].

Protecting the Healthy Kidney: UTI Warning

Because your child has a single functioning kidney, an infection in that kidney (pyelonephritis) is a medical urgency. It can cause permanent scarring, which reduces the kidney’s filtering ability [15][16].

  • Know the Signs: Unexplained fevers (especially without a runny nose or cough), extreme irritability, vomiting, or unusual-smelling urine require immediate medical evaluation.
  • Act Quickly: A suspected UTI in a child with a solitary kidney should be tested and treated promptly. Never take a “wait and see” approach with a fever in an infant with a single kidney.

Common questions in this guide

Does my child need surgery to remove their multicystic dysplastic kidney?
In most cases, surgery is not needed. The standard of care is a 'watch and wait' approach, as the affected kidney naturally shrinks and usually vanishes over time without causing any harm to your child.
How will doctors monitor my child's MCDK over time?
Doctors primarily use regular renal ultrasounds. These painless scans allow them to track the shrinking of the cystic kidney while ensuring the remaining healthy kidney is growing properly to compensate.
Does my child need a VCUG test for their MCDK?
A voiding cystourethrogram (VCUG) is no longer routine for every baby with MCDK. It is typically only ordered if the ultrasound shows abnormalities in the healthy kidney or if your child develops a urinary tract infection.
What are the warning signs of a UTI in a baby with a single kidney?
Signs of a urinary tract infection in an infant include unexplained fevers, extreme irritability, vomiting, or unusual-smelling urine. If you notice these signs, seek immediate medical care to protect their functioning kidney from scarring.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.What is our specific schedule for follow-up ultrasounds over the next year?
  2. 2.Is my child's 'healthy' kidney growing at the expected rate for compensatory hypertrophy?
  3. 3.Are there any findings on the ultrasound that would make you reconsider doing a VCUG?
  4. 4.What symptoms warrant an immediate call to the after-hours line or a trip to the ER?
  5. 5.Under what specific circumstances (like mass effect or severe hypertension) would you ever consider surgery for the dysplastic kidney?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (16)
  1. 1

    Clinical outcome of children with prenatally diagnosed isolated unilateral multicystic dysplastic kidney.

    Huettinger M, Bogner G, Fischer T, et al.

    European journal of obstetrics, gynecology, and reproductive biology 2025; (312()):114112 doi:10.1016/j.ejogrb.2025.114112.

    PMID: 40517513
  2. 2

    The Outcome of Multicystic Dysplastic Kidney Disease Patients at King Abdulaziz Medical City in Riyadh.

    Alamir A, Al Rasheed SA, Al Qahtani AT, et al.

    Cureus 2023; (15(4)):e37994 doi:10.7759/cureus.37994.

    PMID: 37223165
  3. 3

    Multicystic dysplastic kidney (MCDK) in the neonate: The role of the urologist.

    Psooy K,

    Canadian Urological Association journal = Journal de l'Association des urologues du Canada 2016; (10(1-2)):18-24 doi:10.5489/cuaj.3520.

    PMID: 26977201
  4. 4

    Multicystic renal dysplasia, a histomorphological spectrum: Seven years experience from a tertiary care hospital.

    Gupta K, Mandal S, Mallya V, et al.

    Indian journal of pathology & microbiology 2024; (67(2)):385-389 doi:10.4103/ijpm.ijpm_202_23.

    PMID: 38427756
  5. 5

    Multicystic dysplastic kidney - treat each case on its merits.

    Faruque A, Narayanan S, Marley I, et al.

    Journal of pediatric surgery 2020; (55(11)):2497-2503 doi:10.1016/j.jpedsurg.2019.12.008.

    PMID: 31987520
  6. 6

    "Watch and Wait" Strategy for Multicystic Dysplastic Kidney (MCDK): Status Survey of Perceptions, Attitudes, and Treatment Selection in Chinese Pediatric Urologists and Pediatric Surgeons.

    Wang Q, Shi Z, Jiang D

    Frontiers in pediatrics 2020; (8()):423 doi:10.3389/fped.2020.00423.

    PMID: 32850538
  7. 7

    Natural History of Contralateral Hypertrophy in Patients with Multicystic Dysplastic Kidneys.

    Gaither TW, Patel A, Patel C, et al.

    The Journal of urology 2018; (199(1)):280-286 doi:10.1016/j.juro.2017.06.075.

    PMID: 28645868
  8. 8

    The Incidence and Durability of Compensatory Hypertrophy in Pediatric Patients with Solitary Kidneys.

    Wang MK, Gaither T, Phelps A, et al.

    Urology 2019; (129()):188-193 doi:10.1016/j.urology.2019.04.003.

    PMID: 30986483
  9. 9

    Multicystic Dysplastic Kidney: Prenatal Compensatory Renal Growth Pattern.

    Gilad N, Weissmann-Brenner A, Gilboa Y, et al.

    Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine 2021; (40(10)):2165-2171 doi:10.1002/jum.15605.

    PMID: 33351224
  10. 10

    Necessity of performing voiding cystourethrography for children with unilateral multicystic dysplastic kidney.

    Yamamoto K, Kamei K, Sato M, et al.

    Pediatric nephrology (Berlin, Germany) 2019; (34(2)):295-299 doi:10.1007/s00467-018-4079-z.

    PMID: 30255447
  11. 11

    Association Between Multicystic Dysplastic Kidney and the Local Renin-Angiotensin-Aldosterone System: A Pilot Study of a New Biomarker.

    Ishimori S, Ishiko S, Fujimura J, et al.

    Nephrology (Carlton, Vic.) 2025; (30(10)):e70132 doi:10.1111/nep.70132.

    PMID: 41025262
  12. 12

    Voiding Cystourethrogram in Children With Unilateral Multicystic Dysplastic Kidney: Is It Still necessary?

    Blachman-Braun R, Camp MM, Becerra MF, et al.

    Urology 2020; (139()):156-160 doi:10.1016/j.urology.2020.02.005.

    PMID: 32081673
  13. 13

    Knowledge of vesicoureteral reflux obtained by screening voiding cystourethrogram in children with multicystic dysplastic kidney does not change patient management or prevent febrile urinary tract infection.

    Brown C, McLeod D, Ching C

    Journal of pediatric urology 2019; (15(3)):267.e1-267.e5 doi:10.1016/j.jpurol.2019.03.013.

    PMID: 30992197
  14. 14

    Update on Multicystic Dysplastic Kidney.

    Cardona-Grau D, Kogan BA

    Current urology reports 2015; (16(10)):67 doi:10.1007/s11934-015-0541-7.

    PMID: 26255066
  15. 15

    Evaluation of renal injury in children with a solitary functioning kidney.

    Balkı HG, Turhan P, Candan C

    Turkish archives of pediatrics 2021; (56(3)):219-223 doi:10.5152/TurkArchPediatr.2021.20095.

    PMID: 34104912
  16. 16

    Retrospective study to identify risk factors for chronic kidney disease in children with congenital solitary functioning kidney detected by neonatal renal ultrasound screening.

    Urisarri A, Gil M, Mandiá N, et al.

    Medicine 2018; (97(32)):e11819 doi:10.1097/MD.0000000000011819.

    PMID: 30095653

This page provides educational information about monitoring a child with MCDK. Always consult your pediatric nephrologist or urologist for personalized medical advice, ultrasound schedules, and symptom evaluation.

Get notified when new evidence is published on Renal dysplasia.

We monitor PubMed for new peer-reviewed studies on this topic and email a short summary when something meaningful changes.