OSCE Station·Counselling·Multicystic dysplastic kidney
A simulated-parent counselling station: explaining a unilateral multicystic dysplastic kidney found on the newborn scan, and agreeing a follow-up plan with an anxious mother.
You are the neonatal registrar. A term male infant, 2 days old and feeding well, had a renal ultrasound after an abnormal antenatal scan. It shows a unilateral multicystic dysplastic kidney on the left, with a normal-appearing right kidney.
Speak with the mother. Explain the finding, outline what happens next, and answer her questions.
Suggested time: 9 minutesPersona: Mrs H, first-time mother, 31, calm on the surface but frightened. She has been reading online overnight and has slept badly. Opening line: “They told me one of his kidneys is full of cysts — is he going to need a transplant?”
Questions she raises, roughly in this order:
- “Does it mean that kidney doesn’t work at all?”
- “Will the cysts get bigger? Does he need an operation?”
- “Can he manage with just the one good kidney?”
- “Is there anything else wrong with him that you haven’t found yet?”
- “Will he get cancer or high blood pressure later — that’s what the internet says.”
- “So what actually happens next — do we just go home?”
She becomes tearful if the doctor uses technical language without explaining it, and settles if they slow down and check what she has understood.
How would you explain to this mother what a multicystic dysplastic kidney is?
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- It is a severe form of renal dysplasia in which the kidney does not work — the normal kidney architecture is absent and is replaced by multiple large cysts, often described as resembling a cluster of grapes.
- A possible contributor is failure of the ureteric bud to merge and branch properly into the metanephros — in plain terms, the kidney did not form as it should have while the baby was developing.
- It occurs in about 1 in 1,000 to 1 in 4,300 live births, and predominantly affects males and the left kidney — which fits this baby.
She asks whether the cysts will grow and whether he needs surgery. What do you say?
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- Most affected kidneys undergo partial or complete involution over time — that is, the kidney tends to shrink away rather than grow.
- Postnatal management is conservative, with serial ultrasonography to confirm involution and to check that the other kidney is growing appropriately to compensate.
- Surgical removal is reserved for children in whom the multicystic dysplastic kidney grows too large over time — so it is not the starting plan here.
She asks whether anything else might be wrong. How do you answer honestly without alarming her?
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- Most affected babies have only one kidney involved, but about half of cases are associated with anomalies outside the kidneys — so a careful look for other problems is part of routine care, not a sign that something has been missed.
- Between 10% and 25% of congenital anomalies of the kidneys and urinary tract are attributable to genetic disorders, which are frequently associated with other conditions including developmental delay, congenital heart disease, endocrine problems and immunodeficiency — so a genetic evaluation is considered to help with risk stratification and decision-making.
- Both nephrology and urology should be involved for further evaluation and management, with genetics considered where additional congenital anomalies are found.
She has read that he will get high blood pressure or cancer. What is the accurate answer?
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- In unilateral multicystic dysplastic kidney, hypertension and malignancy do not appear to occur at increased rates compared with the general population.
- This can be said plainly and reassuringly — while still explaining that follow-up scans continue, so that involution and compensatory growth of the other kidney are confirmed.
- It is worth acknowledging where her worry has come from rather than dismissing it, and checking what she has taken away before ending.
Summarise the plan you would agree with her before she goes home.
Show model answer
- Conservative management with serial ultrasound scans to track involution of the affected kidney and compensatory growth of the normal one.
- Nephrology and urology input; genetics considered if other anomalies are found.
- Surgery only if the affected kidney grows too large over time.
- Clear, jargon-free explanation, an invitation to ask further questions, and a named point of contact — with a check that she has understood what to expect.
Based on: Fong J, De Beritto T. Congenital Anomalies of the Kidneys and Urinary Tract. NeoReviews, 2024.
Educational material for teaching and revision. Doses, thresholds and management points are for orientation only — always follow your local guidelines and senior clinical advice.