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PubMed This is a summary of 16 peer-reviewed journal articles Updated
Pediatrics · Multicystic Dysplastic Kidney

The Standard of Care: The Watch-and-Wait Approach

At a Glance

The standard of care for Multicystic Dysplastic Kidney (MCDK) is a 'watch-and-wait' approach, avoiding unnecessary surgery. Routine ultrasounds and blood pressure checks are used to ensure the affected kidney safely shrinks while the healthy kidney grows to compensate.

For many years, the standard treatment for Multicystic Dysplastic Kidney (MCDK) was to surgically remove the affected kidney. Today, however, the medical community has shifted toward conservative management, often called the “watch-and-wait” approach [1][2]. This change happened because we now know that most of these kidneys pose no threat and will eventually shrink on their own [3][2].

Why Surgery is Discouraged

Prophylactic nephrectomy (surgery to remove the kidney “just in case”) is generally avoided because the risks of surgery and anesthesia typically outweigh any potential benefits [4][5].

  • The Risk of Cancer is Low: In the past, there was a fear that MCDK could lead to Wilms’ tumor (a childhood kidney cancer), but large studies have shown this risk is extremely low [6][1].
  • The Risk of High Blood Pressure is Low: While the non-functioning kidney can sometimes cause high blood pressure, this is rare and can be managed if it occurs [1][7].

Surgery is now reserved only for rare cases where the kidney is so large it causes a mass effect (pressing on the lungs or stomach, causing trouble breathing or eating), causes severe, uncontrollable high blood pressure, or looks suspicious for cancer on imaging [4][8][9].

The Monitoring Schedule

Instead of surgery, your child will have a routine schedule of “safety checks” to ensure the healthy kidney is thriving and the MCDK is behaving.

  1. Serial Ultrasounds: These are the primary tools for monitoring. Doctors use them to watch the MCDK shrink (involution) and ensure the healthy kidney is undergoing compensatory hypertrophy (growing larger to do more work) [10][11].
  2. Blood Pressure Checks: Since the kidneys play a major role in regulating blood pressure, this will be checked at every routine pediatrician visit [12][13].
  3. Renal Function Tests: Occasionally, your doctor may use a simple blood or urine test to check how well the healthy kidney is filtering the blood [12].

The Trend Away from Routine VCUGs

In the past, every baby with MCDK was given an invasive test called a Voiding Cystourethrogram (VCUG). This test involves placing a catheter into the bladder and injecting dye to check for Vesicoureteral Reflux (VUR) (urine flowing backward toward the kidneys).

Current guidelines have moved away from this being a “routine” test for every child [14][15]. Because VUR is often mild and the VCUG can be stressful, most specialists now only recommend a VCUG if:

  • The ultrasound shows the “good” kidney is swollen or abnormal [16][14].
  • The child develops a urinary tract infection (UTI) with a fever [16][15].

What to Expect Over Time

In about 60% of children, the MCDK will shrink significantly or disappear completely within the first few years of life [3]. Even if it does not disappear entirely, it usually stops growing and remains as a small, harmless piece of tissue [2]. As long as the healthy kidney continues its steady growth, your child’s health and activity levels should be just like those of any other child [1][7].

Common questions in this guide

Why isn't surgery the standard treatment for MCDK?
Surgery is usually avoided because the risks of anesthesia outweigh the potential benefits. Most multicystic dysplastic kidneys pose no threat and will naturally shrink on their own without intervention.
How will my child's MCDK be monitored?
Doctors use routine ultrasounds to watch the affected kidney shrink and ensure the healthy kidney is growing properly. They will also regularly check your child's blood pressure and occasionally test their kidney function.
Does my child need a VCUG test for their kidney?
Routine VCUG tests are no longer recommended for every child with MCDK. Specialists typically only order this test if the healthy kidney looks abnormal on an ultrasound or if your child develops a fever with a urinary tract infection.
When will the multicystic dysplastic kidney disappear?
In about 60% of children, the affected kidney will shrink significantly or completely disappear within the first few years of life. Even if it doesn't vanish entirely, it usually stops growing and remains harmless.

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.At what age can we typically expect the MCDK to be fully shrunken or gone?
  3. 3.Since we are avoiding a VCUG, what specific symptoms of a UTI should I be vigilant for?
  4. 4.How will we track my child's blood pressure as they transition from infant to toddler?
  5. 5.What specific changes on an ultrasound would make you reconsider the "watch and wait" plan?

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

    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
  3. 3

    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
  4. 4

    Neonatal multicystic dysplastic kidney with mass effect: A systematic review.

    Pettit S, Chalmers D

    Journal of pediatric urology 2021; (17(6)):763-768 doi:10.1016/j.jpurol.2021.09.003.

    PMID: 34538561
  5. 5

    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
  6. 6

    Kidney injury rates after unilateral nephrectomy in childhood-a systematic review and meta-analysis.

    Groen In 't Woud S, Gobino A, Roeleveld N, et al.

    Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association 2022; (37(12)):2457-2473 doi:10.1093/ndt/gfac021.

    PMID: 35099015
  7. 7

    Renal function in children with a congenital solitary functioning kidney: A systematic review.

    Hutchinson KA, Halili L, Guerra A, et al.

    Journal of pediatric urology 2021; (17(4)):556-565 doi:10.1016/j.jpurol.2021.03.001.

    PMID: 33752977
  8. 8

    How effective is nephrectomy in curing hypertension in children with unilateral poorly functioning kidney? A systematic review.

    Chandrasekharam VVS, Babu R, Shah M

    Pediatric surgery international 2024; (40(1)):96 doi:10.1007/s00383-024-05676-2.

    PMID: 38568219
  9. 9

    Multicystic Dysplastic Kidney With Mass Effect in a Neonate Treated With Nephrectomy: Case Report.

    Pettit SM, Devan WJ, Chalmers DJ, Zanno A

    Urology 2021; (149()):e11-e14 doi:10.1016/j.urology.2020.11.050.

    PMID: 33309706
  10. 10

    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
  11. 11

    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
  12. 12

    Paediatric multicystic dysplastic kidney disease in Cape Town, South Africa.

    Briggs DC, Hlongwa K, McCulloch M, et al.

    BMC nephrology 2025; (27(1)):12 doi:10.1186/s12882-025-04667-2.

    PMID: 41318409
  13. 13

    Conservative Management of Segmental Multicystic Dysplastic Kidney in Children.

    Han JH, Lee YS, Kim MJ, et al.

    Urology 2015; (86(5)):1013-8.

    PMID: 26277536
  14. 14

    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
  15. 15

    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
  16. 16

    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

This page explains the watch-and-wait approach for MCDK for educational purposes only. Always consult your pediatric urologist or nephrologist regarding your child's specific treatment plan.

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