Dysplastic Kidney
A dysplastic kidney is a developmental condition in which the kidney does not form normally before birth. Instead of healthy kidney tissue, the organ may contain cysts, abnormal tissue, or areas that do not function properly. Dysplastic kidneys may be small, irregular in shape, or poorly functioning, and in some cases, one kidney may be entirely nonfunctional. Many cases are found during childhood, but some are discovered incidentally in adults during imaging.
What is it?
A dysplastic kidney forms when the kidney does not develop normally in the womb. The affected kidney may contain cysts, scar tissue, or malformed structures that prevent it from working well. Some dysplastic kidneys are part of conditions such as multicystic dysplastic kidney (MCDK), in which one kidney is replaced by many cysts. Other cases may show partially formed tissue with limited kidney function.
Imaging helps determine the structure and function of the dysplastic kidney. Ultrasound is often the first study used, showing irregular tissue, cysts, or reduced size. CT or MRI may provide more detail in complex cases, while nuclear medicine scans measure how well the kidney is working.
Important to Know
Most people with a dysplastic kidney live normal, healthy lives—especially if the other kidney is functioning normally. However, dysplasia may be associated with urinary reflux, obstruction, or recurrent infections, which may require monitoring. In childhood, many dysplastic kidneys shrink over time and may become nonfunctional.
Red flag symptoms include recurrent urinary tract infections, flank pain, fever, blood in the urine, or signs of declining kidney function. Follow-up imaging may be recommended to monitor kidney growth, structure, or function, especially in children or individuals with symptoms.