Medullary Spongy Kidney

By | June 8, 2022

In nephrology, the medullary spongy kidney is a cystic medullary kidney disease that affects the renal medulla. Although the disease is present from birth, it sometimes remains asymptomatic throughout life. Possible symptoms are urinary stones and kidney stones in the form of calcium deposits.

What is a medullary sponge kidney?

The medullary spongy kidney is a cystic kidney disease. From birth, both or more rarely only one of the kidneys show cystic changes in the medullary pyramids and papillae in the renal medulla, which are connected to the collecting ducts of the kidneys. The renal medulla and its pyramid are affected by the cystic expansions in the ability to concentrate the urine. For cbd – corticobasal degeneration, please visit

The kidneys of those affected often excrete too little acid or too much calcium and form kidney stones. Urinary stones can also develop. In extreme cases, renal tubular acidosis develops. Although medullary spongy kidney is congenital, it is not classified as a hereditary kidney disease. The following are to be distinguished from the disease:

  • cystic medullary kidney disease types I and II
  • nephronophthisis, which are largely genetic.

A prevalence of 1:5000 to 1:20000 is given for the symptomatic medullary spongy kidney. For asymptomatic medullary spongy kidneys, the prevalence is 1:200.


The disease of the medullary sponge kidney usually occurs spontaneously. The original cause of the cystic changes is still unknown. No specific gene or chromosomal mutation has been linked to the disease. The transmission of the disease seems unpredictable. Due to the unpredictability, scientists assume that a complication in pregnancy is the more likely cause of the disease than a genetic basis.

A combination of genetic and environmental factors is also considered. If such a combination is present, an autosomal dominant inheritance is assumed for the genetic factors. Even if the susceptibility is hereditary in the sense of a genetic disposition, the disease only breaks out in this case when those affected come into contact with environmental factors.

Symptoms, Ailments & Signs

In the case of the medullary spongy kidney, there are congenital cystic enlargements in one or both kidneys. The entire renal medulla does not have to be affected by the cysts. Locally limited changes also occur. Cystic dilatation occurs primarily in the terminal collecting ducts of the renal medulla. The cysts often also form in the papilla tips. The cysts contain calcium oxalate stones.

Although sufferers’ kidneys retain their physiological shape, they have a spongy appearance. In most cases they are also enlarged. The cysts create obstructions that alter the parenchyma. Renal insufficiency does not usually occur. The medullary sponge kidney usually remains asymptomatic for a long time. A good half of those affected remain without symptoms for the rest of their lives. If symptoms occur at all, they are usually urinary and kidney stones, recurrent renal colic, urinary tract infections or hematuria.

Diagnosis & disease progression

The medullary spongy kidney is diagnosed via X-ray imaging. A pyelography can also be used to confirm the diagnosis. With this procedure, it is not the renal calyces that fill first, but the papillary cavities of the kidneys. Although the changes are congenital, the diagnosis is usually made late. In most cases, a diagnosis can only be expected from young adulthood and then usually corresponds to an incidental finding.

In many cases, the diagnosis is made in the fifth decade of life or even after death. The prognosis is relatively favorable. A reduced life expectancy does not apply to the medullary sponge kidney, for example. Kidney and urinary stones made of calcium can cause severe pain and thus reduce quality of life, but they can also remain silent. How great the suffering is in the context of the medullary sponge kidney depends on the individual case.


The medullary spongy kidney causes cysts to form in and around the kidneys. These increase in size and self-healing does not occur. Sometimes, in the worst case, kidney failure can occur, which can also lead to the death of the patient if left untreated. The person affected is then dependent on a donor kidney or on dialysis in order to continue to survive.

However, the medullary spongy kidney does not always have to lead to complications or symptoms, so that many patients live their entire lives with the medullary spongy kidney without any restrictions or symptoms. However, the formation of kidney stones or urinary stones can also increase. Other infections of the kidneys or urinary tract are also possible.

The increased supply of liquid and various therapies can limit the symptoms of the medullary spongy kidney relatively well. Complications usually do not arise. However, it is not uncommon for patients to be dependent on medication. If the treatment is successful, the patient’s life expectancy is not reduced and there are no further complications.

When should you go to the doctor?

Most patients with medullary spongy kidney do not experience any symptoms or abnormalities. This leads to the fact that in some cases no diagnosis takes place in the course of life. Everyone should take part in the regularly offered check-ups and routine examinations, even if they are symptom-free. These take place in the first years of life and are offered to adults aged 35 and over. The need to consult a doctor also arises as soon as the person concerned notices irregularities or problems in the kidney area. A doctor should be consulted if there is a change in kidney activity or a diffuse feeling.

If there are problems with urination, blood in the urine, abnormalities in fluid intake or ulcers in the kidney area can be felt, a doctor should be consulted. Swelling or a feeling of pressure in the upper body are indications of existing cysts that should be clarified by a doctor. A persistent urge to urinate immediately after going to the toilet, repeated infections of the urinary tract or the development of urinary and kidney stones indicate the presence of a medullary sponge kidney. If colic occurs, a doctor must be consulted as soon as possible. Since there is a risk of organ failure, an emergency service should be alerted immediately in the event of cramps and severe pain in the kidneys.

Treatment & Therapy

A causal treatment is not yet available for the medullary sponge kidney. Therapy is therefore exclusively symptomatic. Both drug therapies and interventions can take place as symptomatic treatment. A stone crushing is carried out, especially in the case of stone diseases in the urinary tract or the kidneys. Smaller stones are broken up by shock waves.

Without any operation or anesthesia, shock wave devices transmit shocks to the tissue fluid, which shatter the calcium concretions. The patient excretes the shattered stones with the urine. Larger concretions cannot be removed in this way. Even with a large number of stones, surgical removal is the treatment of choice. In order to avoid stone formation or to reduce the risk of recurrence after rupture, patients with medullary sponge kidneys should drink as much water as possible.

A drinking quantity of 2.5 liters per day is the minimum. However, stone formation can also be prevented by drug treatments. Against hypercalciuria and as prophylaxis of nephrolithiasis, those affected receive thiazides, for example, which also reduce the risk of urinary and kidney stones. Urinary tract infections are usually treated with antibiotic therapy.

Outlook & Forecast

The prognosis of the medullary sponge kidney is based on the individual severity of the disease. Nevertheless, no spontaneous healing is to be expected. Cysts form on the kidneys that require medical attention. Otherwise, there is a risk of the disease spreading and thus an increase in health impairments.

If the course of the disease is very unfavorable and the genetic disease is severe, the affected person may die prematurely. The functional activity of the kidneys is restricted due to the formation of new tissue. If there is no timely medical treatment, irreversible damage to the organ can occur. In addition, a loss of organ activity is possible. In these cases, the disorder is life-threatening. The victim is at risk of premature death.

If medical care is initiated as soon as the first irregularities in the formation of new tissue occur, the symptoms can often be completely cured. A crushing of the cysts or stones is initiated. The foreign bodies are then transported away and excreted via the organism. In addition, surgical interventions can be carried out, which also follow the removal of the foreign body. This treatment method increases the risk of complications. Nevertheless, it is often the only chance of recovery. In the further course of life, the foreign bodies can form again at any time.


So far, the medullary sponge kidney cannot be prevented because the causes of the disease have not been conclusively clarified. Nevertheless, the risk of symptoms can be reduced if those affected drink enough fluids, for example.


Since the disease and the treatment of the medullary spongy kidney are relatively complex, the aftercare is aimed at trying to find a good way of dealing with the situation. This can lead to psychological upsets, which should sometimes be clarified by a psychologist. Therapy or contact with other sufferers can help to better accept the disease. This can increase well-being regardless of the fact that treatment continues.

A medullary spongy kidney can lead to various complications and discomfort in the patient if left untreated. Those affected should see their doctor on a regular basis and strictly follow the instructions in their own interest. This also includes the diet, which is intended to relieve the kidneys during regeneration. In this respect, aftercare aims to adjust to the unfamiliar situation and to promote a healthy lifestyle. The further course depends very much on the severity of this disease, so that a general prediction is usually not possible. In some cases, the life expectancy of the patient is also limited.

You can do that yourself

If symptoms of kidney disease appear, a doctor should be consulted first. The medullary sponge kidney can be treated symptomatically by those affected, but this requires a comprehensive examination by a doctor.

A strict diet must be followed in addition to drug therapy, which serves to reduce the pain. Drink plenty of fluids (at least three liters a day), especially before bedtime and after meals. The daily diet should consist mainly of bland foods. Depending on how severe the medullary sponge kidney is, foods such as vegetables, fruit and low-salt foods are recommended. Meat and sausage should be avoided as far as possible. Coffee and alcohol should also be avoided as they put an additional strain on the kidneys.

In general, care must be taken to ensure that the intestinal flora is intact. In consultation with the doctor, detoxification or fasting can be carried out to strengthen the health of the intestines and kidneys. General measures such as exercise and avoiding stress have a positive effect on the entire body and thus also on the diseased kidney. If the symptoms increase despite all measures, it is best to speak to the responsible doctor again.

Medullary Spongy Kidney