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Multicystic dysplastic kidney (MCDK): what it is, the problems it can cause, how it is found, and the checkups
For a parent whose baby has, or may have, a multicystic dysplastic kidney (a kidney filled with cysts that does not work, most often seen on an ultrasound in pregnancy), and for the people beside them. It passes on, by name, what the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK, part of the NIH) says: what it is, what causes it, how common it is, the problems it can cause, the symptoms, how it is found, the treatment and the checkups, and food. It builds the questions to ask and prints a wallet card. Nothing is saved.
Right now
- Your baby or child has a fever, seems in pain, or may have a urinary tract infection? Call the provider the same day; for a young baby with a fever, call right away, day or night. If you cannot reach the provider, go to an emergency room (ours).
- A baby or child very ill, hard to wake, or struggling to breathe? Call 911 (ours).
- Thoughts of suicide, or all too much? Call or text 988, any hour, free (ours).
More help
- On this site: One kidney (a solitary kidney) · Kidney disease in children · High blood pressure · Polycystic kidney disease · Kidneys, bladder and urine: find the right page.
- Tests: Urinary tract imaging · How your kidneys work. If the kidneys fail: Kidney failure · A kidney transplant · Hemodialysis · Peritoneal dialysis. Other pages: Pregnancy and a new baby.
- When it is hard to pay: When you need a doctor and can’t pay · Medical bills. Getting ready: Get ready for your appointment.
- In an emergency: Help right now (988, 911). All our free tools.
Kidneys, bladder or urine, and not sure this is the right page? The pages on this site for bladder infections, kidney stones, blood in the urine, bladder pain, bladder leaks, the prostate, kidney disease and bedwetting, on one list.
Other guides on this site that go with this page
Free to read. We chose these ourselves; no professional did. Each guide was written with AI and has not been reviewed by a professional. They are general information, not advice.
- Kidney infection (pyelonephritis): the signs, sepsis, and the treatment: a kidney infection (pyelonephritis): the signs at each age, sepsis and when it is 911, who is more likely to get one, the tests, the antibiotics, and preventing the next one.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor or nurse has reviewed it. The facts were read on October 21, 2026 on NIDDK’s (NIH) page Multicystic Dysplastic Kidney (last reviewed January 2023, so some advice may have changed since). The numbers (between 1 in 1,000 and 1 in 4,300 babies each year, from a small study) are NIDDK’s, and we add none. We name no medicines and give no doses. Ours: calling the provider the same day (right away for a young baby with a fever); going to an emergency room if you cannot reach the provider; the 911 line; asking who checks the baby after birth; asking about a genetics professional; the lines on checkups; 988; the questions to ask; the card; the links to our other pages; and the order of the steps. What we left out: NIDDK’s section on research studies, its reference, and its thanks. Nothing you tick or type here is saved or sent.