Renal failure

What is acute renal failure?
Acute renal failure or acute renal failure is the sudden loss of kidney function.

This occurs especially in the elderly and can cause serious problems.

The kidneys are two bean-shaped, fist-sized organs located in the back of the abdomen on either side next to the spine.
The kidneys remove waste products of the organs and maintain the balance of water, salt and other minerals (electrolytes) in the blood.

When the kidneys stop working, the waste products, fluids and electrolytes accumulate in the body.


What happens under normal conditions?

Healthy kidneys produce urine to cleanse the blood of the waste products.
They also establish the balance of important elements such as sodium and potassium and provide the necessary hormones for regulating blood pressure or the production of red blood cells.

What are the different types of renal insufficiency?

There are two main types of renal failure: acute and chronic renal failure.

  • Acute kidney failure (ANV) occurs when the kidneys suddenly stop filtering waste products from the blood.
  • Chronic kidney failure (CNV) develops slowly and initially has few symptoms.

What is the cause of acute renal failure?

Acute renal failure has three main causes:

  1. The sudden drop in blood flow to the kidneys. This blood flow can be reduced by significant blood loss due to injury or by an infection called sepsis. The lack of fluid in the body (dehydration) can damage the kidneys.
  2. Damage caused by some medications, poisons or infections. Most people do not experience kidney problems after taking medication.
    People with long-term serious health problems increase the risk of getting kidney problems caused by medication.
  3. A sudden closure that prevents the outflow of urine from the kidneys.
    The occlusion can be caused by kidney stones, a tumor, injury, or prostate enlargement.

In children, disability may be caused by congenital urinary defects.

Examples of drugs that can damage the kidneys:

  • Antibiotics such as gentamicin and streptomycin.
  • Anti-inflammatories such as naproxen and ibuprofen.
  • Some antihypertensive agents (antihypertensives) such as ACE inhibitors.
  • Some opiates such as morphine.
  • Contrast agents used in some X-rays.

Acute renal failure is more common in:

  1. Elderly;
  2. people with long-term conditions such as liver and kidney disease, diabetes, high blood pressure, heart failure or obesity;
  3. people who are already ill in hospital or intensive care;
  4. Heart or stomach surgery and bone marrow transplants can increase the risk of kidney disease; in the postoperative period, renal insufficiency may develop.

Symptoms and consequences of renal failure

Symptoms of acute renal failure include:

  • reduction of urine production,
  • swelling, especially of the legs and feet,
  • Anorexia
  • nausea and vomiting,
  • mental confusion, anxiety, restlessness or drowsiness;
  • Back pain, especially one-sided right or left.

Some people have no symptoms at all. In sick people, the cause of kidney failure can also provoke other symptoms.

Diagnosis of acute renal failure

Often, acute kidney failure is diagnosed when someone is hospitalized due to another problem. In the hospital, a kidney problem can also be detected through examinations carried out to diagnose other diseases.
Those who are not in the hospital but have symptoms of kidney failure can contact their family doctor, who will ask what medications have been taken and what tests have already been done.

Urine and blood tests can be used to check kidney function. Chemical analysis can show normal levels of sodium, potassium and calcium.
Also, an ultrasound examination can be performed, which allows the doctor to create an image of the kidneys.

Therapy for renal failure

Usually, therapy for acute renal failure requires hospitalization.
The duration of stay depends on the cause of the kidney failure and the recovery time of the kidneys.

Treatment of the underlying cause of renal insufficiency
Treatment options depend on the cause of kidney failure.

Treatment of complications until recovery of the kidneys
The doctor should prevent complications and allow the healing process of the kidneys.
Treatments that help prevent complications include:

  • Therapies to balance the amount of fluid in the blood. If acute renal insufficiency is due to a lack of fluid in the blood, the doctor may prescribe intravenous injection of fluid. In other cases, kidney failure can lead to fluid accumulation and swelling of the arms and legs. In these cases, the doctor may prescribe medications (diuretics) that help remove fluids from the body, such as furosemide (Lasix).
  • Drugs for controlling the level of potassium in the blood. If the kidneys cannot properly filter potassium from the blood, the doctor may prescribe calcium, glucose, or sodium polystyrene sulfonate (Resonium) to prevent the accumulation of large amounts of potassium. An excess of potassium in the blood can cause arrhythmias and muscle weakness.
  • Drugs to restore the level of calcium in the blood. If the level of calcium in the blood is too low, the doctor may prescribe a calcium infusion.


  • Dialysis to remove toxins from the body. If toxins accumulate in the blood, temporary hemodialysis (dialysis) may be required to remove the waste products and excess fluids from the body during the recovery process of the kidneys. The dialysis machine works like an artificial kidney and can also help eliminate excess potassium from the body. In dialysis, a catheter is inserted into the patient’s abdomen and a machine pumps the blood out of the body using an artificial kidney (dialyzer) that filters out the waste products. Then the blood is returned to the organism.
    Patients receiving this therapy are not allowed to drink much.

There are no natural remedies for treating kidney failure.

Kidney transplantation

If kidney function drops below 10% of its normal capacity, conservative treatment methods are usually no longer sufficient to control the symptoms of renal insufficiency.
Dialysis is required immediately if a patient has uncontrolled symptoms (for example, nausea and anorexia), high levels of potassium in the blood that cannot be treated medically, pericarditis (inflammation of the pericardium) and nerve damage.
Kidney transplantation is now the best therapy for many people with end-stage renal insufficiency.
Over the past 5-10 years, most hospitals have achieved very high success rates by developing more specific and less toxic immunosuppressants.
The success of transplantation technology has increased waiting times for organs from the deceased, and many patients remain on dialysis for years until an organ is available.

The advantage of a living donor is the possibility to perform the transplant with short waiting times and in many cases this procedure is provided before the recipient needs dialysis.
In addition, kidney transplant results are better in living donors than in deceased donors.
In large hospitals, kidney transplants from related or unrelated living donors have become an interesting option to avoid waiting times for organs from deceased donors.

Can acute kidney failure cause permanent damage?

Doctors are able to solve the problems caused by renal insufficiency.
Treatment lasts a few days or weeks. The kidneys of these individuals function well enough to live normally.
Some people may experience permanent damage to the kidneys, leading to chronic kidney disease.
These patients must undergo regular dialysis or undergo a kidney transplant.
Older people and people suffering from other diseases may not be able to recover.
Most people die from the disease that caused the kidney failure.

How long can you live? Prognosis and life expectancy in renal failure

Acute renal failure and immediate complications such as water retention, high acid and potassium levels and increased urea nitrogen content in the blood can be successfully treated.
The global survival rate is about 50%.

Unfortunately, death is inevitable in at least 50% of people if several organs fail at the same time.
The survival rate is 90% if the acute renal insufficiency is due to a reduction in blood flow due to haemorrhage, vomiting or diarrhoea, i.e. if the state of health can be restored with therapy.
About 10% of people who survive acute kidney failure require dialysis or kidney transplantation as kidney function gradually deteriorates.
With dialysis, patients can continue to live for many years.
Women with renal insufficiency who are planning pregnancy should talk to a nephrologist beforehand.

Is it possible to prevent acute renal failure?

To prevent acute renal insufficiency, it is best to take the necessary measures to stay healthy.
When hospitalized for surgery or illness, one should be aware of the risks and complications associated with the procedure in question.
Any changes in urine production should be reported immediately.
Follow your doctor’s instructions

Frequently asked questions about kidney failure

The doctor thinks that an enlargement of the prostate has caused slight damage to the kidneys.

What can be done?
Untreated closure of the bladder by benign prostatic hyperplasia (BPH) can lead to chronic renal failure. If this is the only cause of CNV, treatment of prostatic hyperplasia must be considered.
Most often, other symptoms of BPH manifest themselves before kidney failure occurs. A urologist can point out the different treatment options.

I have diabetes, but my doctor says my kidneys are healthy. Will I suffer from renal insufficiency like my grandmother?

Recent studies have shown that careful control of sugar levels can prevent all kinds of problems associated with diabetes, including renal insufficiency.
Regular check-ups and laboratory analyses can help the doctor prescribe the right medications for diabetes and for the kidneys.

I need a kidney transplant, but I don’t want to be on a list. Can my best friend donate a kidney to me?

If your friend is healthy, has a compatible blood type, and has various blood tests and screenings, they may be eligible as a donor. Kidney transplants from unrelated living donors are becoming increasingly common.

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