The two kidneys play a major role in the organism, even if they are rather small organs with their almost 200 grams each weight and 10 cm in length. If their function of excreting waste products and poisons no longer suffices, many complaints will result that can be life-threatening without treatment.
What is renal insufficiency?
Kidney functions are diverse - one of the most important is to eliminate urinary urinary nitrogen-containing metabolic end products and toxic substances. If the kidney tissue is affected, this ability is limited and the substances accumulate in the organism and poison it. In addition, there is an overhydration of the body.
Such kidney failure can either be sudden (acute renal insufficiency) or progressively worsen over a prolonged period (chronic renal insufficiency). Since in the latter form, the healthy kidney tissue can take over the tasks of the diseased part for a long time, the disease is often discovered accidentally or only at a late stage.
Causes: How does kidney failure develop?
The causes are manifold and different in the two forms. The acute renal failure is usually the result of a sudden lack of blood flow to the kidneys. This may be due to sudden loss of blood, such as occurs after a serious accident or by a sudden drop in blood pressure as in shock. Common cause is also a poisoning, which damages the kidney tissue (eg by bacterial toxins with infections) or an allergischen damage of the kidney corpuscles (usually by medicaments, mushrooms or Röntgenkontrastmittel).
In contrast, chronic renal insufficiency is usually caused by inflammation of the renal corpuscles (glomerulonephritis) or kidney damage as a result of long-term diabetes (diabetic nephropathy) or hypertension. Other rare causes include kidney stones, cystic kidneys, inflammation of the renal pelvis or urinary tract and abuse of certain analgesics (especially phenacetin).
Who is affected?
In 2009, there were about 95, 000 patients in Germany whose kidney function was so poor that they had to undergo treatment - that is more than one person per thousand inhabitants. About 70, 000 of them were treated with dialysis, nearly 25, 000 with a kidney transplant. Currently, about 1.5 times more women than men are ill.
It is noticeable that in recent years not only the incidence (number of patients in need of treatment) and the prevalence (number of patients per million inhabitants) are rising continuously, but also the average age of those affected is steadily increasing. The fact is not surprising, considering that, on the one hand, as a whole, people are getting older and, on the other hand, patients with chronic illnesses such as diabetes or hypertension live longer than before.
This makes kidney disease not only a medical but also an economically relevant problem. The costs for dialysis and concomitant diseases are around 44, 000 €, those for kidney transplants at 18, 000 € per year. The total cost of all renal replacement therapy (dialysis and transplantation) is currently estimated to be between € 2.0 billion and € 2.5 billion.
Symptoms and course in renal insufficiency
The symptoms that occur depend on the form and stages of the disease as well as the underlying and accompanying illnesses.
Acute renal insufficiency
First of all, the symptoms of the underlying disease, such as the serious infection, are usually in the foreground. After hours to days, the urine production (oliguria) diminishes until it is completely dry (anuria). Those affected are tired, they are sick and they are less and less responsive. Since water is stored in the body, especially the lungs, breathing difficulties can occur. Also cardiac arrhythmias are not rare.
The doctor differentiates during the course of four phases, which are also different in the blood. With timely treatment, the acute renal failure in many cases can completely regress - but if it sets too late, it can be fatal.
Chronic renal insufficiency
This form also runs in four stages. As long as the kidneys can compensate for the functional failure, there are often no symptoms or only increased nocturnal urination. However, the changes can already be detected in the laboratory. This stage can take several years. Often it comes then to a Leistungsknick and malaise.
The increasing destruction of kidney tissue leads to more and more discomfort on various organs due to the retained waste products and the water. These include the yellowing and itching of the skin by the stored urinary disorders, sleep and concentration disorders, headache, nausea, vomiting, diarrhea and taste disorders. High or low blood pressure, cardiac arrhythmia or inflammation and respiratory problems also occur. In addition, it comes to anemia (by the reduced erythropoietin formed by the kidney, which is used for blood formation), coagulation disorders, increased susceptibility to infections and bone softening (since the kidney is also involved in the vitamin D metabolism).
In the last stage of the four stages, the end-stage renal insufficiency, urea poisoning also causes severe nervous system disorders such as seizures, confusion and unconsciousness, as well as coma. Only a lifelong dialysis treatment or kidney transplant will save the patient from death at this stage.
How is the diagnosis made?
In addition to the complaints, the kidney levels in the blood are the most important diagnostic aid. To be able to counteract a deterioration in kidney function in good time, they must therefore be regularly monitored in kidney patients. In order to check the water retention, import and export can be accounted for (ie the liquid supplied is documented and the body weight is measured). In addition, urine and ultrasound examinations are carried out. Further tests depend on the symptoms and the suspected underlying disease.
Treatment: What is the therapy?
The treatment also depends on the form and the stage. Acute renal failure requires fast hospitalization. There, on the one hand, the underlying disease is treated - only when it is over, the prognosis is favorable, since the tissue changes usually form back. If she can not be controlled, the mortality rate is very high. On the other hand, there is a symptomatic therapy with infusions, adapted nutrition and medication. Often, dialysis is required temporarily.
In the chronic form, which is always associated with irreversible tissue loss, in the first three stages, the treatment of the underlying disease (eg, a good attitude of diabetes or high blood pressure, the removal of kidney stones, etc.) and a diet is in the foreground. Diuretic drugs are often prescribed as well as medications to counteract the bone changes. For the anemia, the missing hormone erythropoietin is administered. In the last stage, the patient has to undergo a lifelong dialysis or a kidney transplant.
Diseased people have to pay attention to nutrition
In order to delay dialysis for chronic kidney failure as long as possible, the cooperation of the person concerned is of great importance. Very important is the close and regular contact with the doctor, preferably a kidney specialist (nephrologist). Compliance with the low-protein, low-phosphate, low-potassium, calcium-rich diet is also important in preventing deterioration of kidney function. Even banal infections must be treated as quickly as possible.
It is important to know that many, even non-prescription drugs are excreted via the kidney, so their dose must be reduced. Therefore, the doctor should always be asked for advice with self-medication.