Nephroblastomatosis is a rare disease affecting the kidneys. Nephroblastomatosis is manifested by the persistence of kidney tissue in the embryo after birth. The tissue represents a so-called metanephric blastema and is immature. It increases the likelihood that the patient will develop malignant degeneration of the kidney tissue.


What is nephroblastomatosis?

Basically, nephroblastomatosis is a different disease than nephroblastoma, with which it is often confused. However, this disease represents a malignant tumor of the kidneys in childhood patients. The metanephrogenic blastema of nephroblastomatosis develops in the fetus during the course of pregnancy. See phonejust for Laryngeal Paralysis Meaning.

In the majority of cases, the fetal tissue transforms into renal parenchyma, which contains tubules and glomeruli. Only in about one percent of people are parts of the remaining embryonic tissue detectable in autobiopsies. The remnants of blastema usually clear up in affected babies during the first four months after birth.

If complete regression does not occur, extensive damage and deformation of the parenchyma of the kidney occur. In addition, the tissue often enlarges. Nephroblastomatosis is divided into three different types based on their localization to the lobes of the kidneys. There is an intralobar, a perilobar and a panlobar form of nephroblastomatosis. In the last type, the kidney enlarges after a relatively short time.


The exact causes of the pathogenesis of nephroblastomatosis have not yet been sufficiently researched, so that reliable statements about the reasons for its development are not yet possible. However, the mechanism of disease development is partially known. In embryos, the so-called metanephrogenic blastema develops in the kidneys, which regresses over time.

In healthy people, kidney parenchyma with tubules and glomeruli develops in place of the fetal tissue. However, in nephroblastomatosis, a small proportion of metanephrogenic blastema remains after birth. This creates the risk that the tissue of the kidney will degenerate malignantly. The exact reasons for the persistence of metanephrogenic blastema in infants have not yet been conclusively clarified.

Symptoms, Ailments & Signs

In nephroblastomatosis, kidney tissue from the embryo, the so-called metanephrogenic blastema, remains in the kidney even after birth. Normally, this fetal tissue rebuilds completely. The patients are exposed to an increased risk of malignant degeneration of the kidneys.

Nephroblastomatosis is therefore a precancerous condition. In the majority of cases, the typical changes of nephroblastomatosis are present in both kidneys. More rarely, a single kidney is affected by the abnormalities.

In about half of the patients, a so-called Wilms tumor forms as a result of the nephroblastomatosis. Its diagnosis is often only made by chance during other investigations. Nephroblastomatosis is also associated with a number of other diseases and syndromes. D

These include, for example, hemihypertrophy, multicystic renal dysplasia and Beckwith-Wiedemann syndrome. Nephroblastomatosis also frequently occurs in connection with multilocular cystic nephroma and aniridia.

Diagnosis & course of disease

In many cases, a diagnosis of nephroblastomatosis is only made by chance. Acute symptoms are often hardly noticeable as long as the nephroblastomatosis has not yet led to a malignant degeneration of the kidney tissue. Therein lies the danger of nephroblastomatosis, since it is often detected too late.

The patient’s medical history focuses, among other things, on chronic diseases or congenital syndromes that have an association with nephroblastomatosis. Appropriate information makes it easier for the doctor to diagnose nephroblastomatosis. In the clinical examination of the patient, various methods contribute to the diagnostic result.

Imaging procedures of the kidneys are particularly important. The doctor often performs an ultrasound, whereby the damage to the kidney tissue is partially visible. This is because they react less to the echo sound than the surrounding tissue areas.

In addition, a CT scan is often used to diagnose nephroblastomatosis, with the patient taking special contrast media beforehand. Since the lesions hardly absorb any contrast medium, the damaged areas are relatively easy to identify. An MRI examination is also possible. The doctor carries out a differential diagnosis and distinguishes nephroblastomatosis from renal lymphomas in particular, since there is a potential for confusion here.


Due to nephroblastomatosis, the child can suffer from serious kidney problems. This may also significantly reduce the patient’s life expectancy. The patients suffer from various malignant degeneration of the kidney tissue. In the worst case, this can also lead to kidney failure, which can ultimately lead to death.

Complications usually arise when nephroblastomatosis is diagnosed late. For this reason, pregnant women rely on various examinations to avoid complications. Nephroblastomatosis can be treated relatively well if diagnosed early. There are no particular complications for the patient or the mother.

In most cases, patients are dependent on chemotherapy, which, however, is associated with various side effects. Furthermore, those affected are still dependent on surgical interventions after birth. However, in most cases there are no particular complications. The degeneracies can be removed in the process. However, the cancer can also spread to other regions of the body, so that the children are also dependent on regular examinations.

When should you go to the doctor?

Nephroblastomatosis is a rare disease that is usually diagnosed by accident. A medical evaluation is necessary if symptoms such as kidney pain or repeated fever are noticed. If nephroblastomatosis is actually the underlying cause, it must be diagnosed before the kidney tissue becomes malignant. For this reason, all complaints that indicate a serious condition must be clarified by the family doctor and, if necessary, by a nephrologist. Otherwise, serious complications can occur, which in the worst case can lead to death.

Parents who themselves suffer from kidney disease should have a genetic test carried out. Since the causes of the disease are not known, a specific diagnosis is not possible, but various warning signs should always be examined. People who suffer from kidney disease or even nephroblastomatosis must see a doctor immediately if they see the warning signs mentioned. The disease must be closely monitored so that degeneration and other complications can be acted upon quickly. In addition to the family doctor and nephrologist, various internists and neurologists may be responsible.

Treatment & Therapy

Since an existing nephroblastomatosis in patients carries a high risk of malignant degeneration of the kidneys, regular examinations are of great importance. The intervals between the individual examination appointments are relatively short in order to treat possible degeneration quickly and specifically. In addition, there are options for active therapy of nephroblastomatosis.

So-called wedge resections and chemotherapy can be considered. Patients usually undergo appropriate surgical procedures to surgically remove damaged kidney tissue. This partially reduces the risk that nephroblastomatosis will lead to malignant degeneration of the kidneys.

Outlook & Forecast

If left untreated, nephroblastomatosis has an unfavorable course of the disease. Those affected are at an increased risk of developing malignant cancer. Nephroblastomatosis is classified as a harbinger of tumor disease. Therefore, the person concerned is at risk of premature death if medical care is not initiated in good time. The stage of the disease at the time of diagnosis is therefore particularly important for the development of a prognosis.

The later the disease is diagnosed and treated, the more unfavorable the further course will be. The difficulty lies in recognizing the disease. It often remains undetected for a long time because it hardly causes any impairments in everyday life. In many of those affected, the changes in the tissue are recognized on the basis of incidental findings.

The prospect of recovery therefore also depends on the prevention that the patient loves. Regular check-ups can therefore lead to rapid detection of health changes. The fastest possible intervention is possible in these cases and can contribute to a full recovery in the further course.

If malignant tissue growths have already developed, the affected person needs surgery and cancer therapy. Otherwise, there will be a significant reduction in general life expectancy. The further development is strongly dependent on the general state of health of the person concerned.


It is not yet possible to prevent nephroblastomatosis. The basis of the development of the disease is already formed in the fetus in the womb. For this reason, an influence is hardly possible. In addition, the causes of nephroblastomatosis are currently still insufficiently known, so that there is a need for further research.


In the case of nephroblastomatosis, in most cases the patient has only a few and usually only limited direct follow-up measures available. For this reason, the person concerned should contact a doctor very early on, so that there are no further compilations or, in the worst case, death of the person concerned. An early diagnosis usually has a very positive effect on the further course of the disease.

Most of those affected are dependent on regular checks and examinations by a doctor in order to detect and remove tumors in the kidneys at an early stage. Examinations after a successful removal of the tumor are also very important, as this allows further tumors to be detected at an early stage. When it comes to treatment, many of those affected by nephroblastomatosis also depend on the help of their own family and relatives.

Psychological support can also prevent depression and other mental upsets. Contact with other nephroblastomatosis patients can also be very useful, as this leads to an exchange of information that can improve the quality of life of those affected. In many cases, the disease limits the life expectancy of those affected.

You can do that yourself

As a chronic disease, nephroblastomatosis often leads those affected and their families to focus on the clinical picture. Many sufferers feel powerless and at the mercy of the disease. However, it is important for patients and their loved ones not to experience the condition as something inevitable or inescapable. In order to delay the course of the disease, those affected and their relatives should therefore actively cooperate.

The use of preventive programs for early detection of the disease and regular visits to the nephrologist are a matter of course. But patients and their relatives should also familiarize themselves with the clinical picture and inform themselves. This increases knowledge about risk factors and promotes responsible action. On the one hand, this includes regularly checking your blood pressure yourself. Another important part of the active cooperation of the patients and their relatives is an adjustment and conversion to a lactose- and gluten- free diet. Becoming active yourself and delaying the progression of the disease also means taking advantage of sporting activities such as rehabilitation sports.

Chronic diseases represent a significant burden for patients and their families. It often means a great deal of relief to get support from a self-help group – online or on site. If necessary, the psychosocial counseling centers in the districts can also help.