Medullary Sponge Kidney: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Medullary Sponge Kidney?
A nephrologist, a doctor who treats kidney disease, usually manages medullary sponge kidney. A urologist, a doctor who treats the urinary tract and kidney stones, often helps when stones need treatment. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is medullary sponge kidney?
Medullary sponge kidney is a rare kidney disorder. Small cyst-like pockets form in the collecting ducts, the tiny tubes in the kidneys that gather urine. One or both kidneys may be affected.
The first signs can be blood in the urine, calcium kidney stones, or an infection. It is also called sponge kidney or Cacchi-Ricci disease. It is thought to occur in 1 in 1,000 to 5,000 people in the United States.
Symptoms
The first symptoms are often one of these:
- Blood in the urine.
- Calcium stones in the kidneys.
- Signs of a urinary infection, such as passing a lot of urine and burning or pain when urinating.
Stones can cause low back pain over the kidneys, and pain in the lower back and lower belly. Passing small stones can be very painful. In a small number of cases, large stones block the flow of urine. Then repeated urinary infections and kidney damage may occur.
Other signs can include abnormal urine color, chills, fever, and nausea and vomiting.
The most common complication is that the kidneys lose some ability to concentrate waste in the urine. This can let acid build up in the blood. Rare complications include severe kidney damage and kidney failure.
Symptoms can begin at any age. They usually develop in the teen years or in adults between 30 and 50 years old.
Causes and who gets it
The exact cause is not known. Most cases happen for no clear reason. Some cases are thought to run in families, but this has not been proven.
Some studies suggest a possible link with an overactive parathyroid gland. It may also develop in people with Beckwith-Wiedemann syndrome, a rare condition present at birth.
The disorder affects slightly more women than men. About 13 percent of all people who develop kidney stones are eventually diagnosed with it.
How doctors diagnose it
Doctors start with a careful clinical evaluation. Special X-ray studies, such as intravenous urography, can show widening of the collecting ducts, cysts, or kidney stones.
A CT scan, a detailed X-ray picture, can show calcium deposits that may later form kidney stones. In some people, doctors measure how well the kidneys filter, and it may be lower than normal.
Because stones are common with this disorder, doctors may also check blood calcium, test urine for crystals and red blood cells, and test kidney function.
Treatment
Treatment is aimed at symptoms, stones, and infections. People with this disorder should drink enough fluids to pass about 2 liters of urine each day. For kidney stones in general, not drinking enough fluids is the biggest risk factor.
People who have too much calcium in the urine may benefit from long-term treatment with thiazide diuretics, also called water pills, along with a high fluid intake. In some people, a low calcium diet may help prevent stones.
Many people have repeated urinary infections and may need antibiotics to help prevent future infections. Doctors should check patients at least once a year, with urine tests and urine cultures.
Stones may be broken up with shock waves, a treatment called ESWL. It has not been determined if ESWL helps with stones in the kidney tubules. For kidney stones in general, surgery is often needed if a stone is too large to pass on its own, is growing, or the pain cannot be controlled.
Genetic counseling may help if the disease appears in other family members. In rare cases of kidney failure, dialysis may be needed.
When to see a doctor
Contact your provider if you have blood in your urine, cloudy or bad-smelling urine, or burning when you urinate.
Call 911 or go to the emergency room if you faint, have breathing problems, have a sudden change in mental state such as confusion, have severe or constant vomiting, or have sudden severe pain in your back or side. Also go right away if you have a fever or chills with kidney stone pain. A blocked stone with an infection can damage the kidney.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Such a doctor can review your symptoms and test results and arrange urine tests and imaging. They can also help with follow-up and refer you to a kidney or urinary specialist.
Common questions
Is medullary sponge kidney common?
No, it is a rare disorder. It is thought to occur in 1 in 1,000 to 5,000 people in the United States.
Does medullary sponge kidney cause kidney stones?
Yes, calcium stones may form in the kidneys of some people who have it. About 13 percent of all people who develop kidney stones are eventually diagnosed with medullary sponge kidney.
Can medullary sponge kidney lead to kidney failure?
Rarely. Rare complications can include severe kidney damage and kidney failure. In rare cases of kidney failure, dialysis may be needed.
How often should I have a checkup for medullary sponge kidney?
Patients should be checked at least once a year. The visit includes routine urine tests and urine cultures.
Sources
- NORD (National Organization for Rare Disorders) - Medullary Sponge Kidney
- MedlinePlus - Kidney stones
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
