The kidneys not only filter the blood, they also remove metabolic products, regulate the hormonal balance and maintain the body's electrolyte balance. Proper kidney function ensures optimal conditions for the work of all organs and tissues in the body.
The basic functional unitof the kidneyis the nephron. It consists of the glomerulus (it has a filtration function), a system of straight and tortuous tubules and a collecting coil in which the processes of passive and active reabsorption as well as passive and active secretion take place. There are approximately 1-1.2 million nephrons in each human kidneynephrons .
Kidneys are not only a filter
Although they are small (approx. 150 g each), they play a very important role in the body. Not only do they filter, they are also responsible for maintaining a constant internal environment, i.e.
- maintain water-electrolyte and acid-base balance;
- remove waste products;
- regulate the calcium-phosphate, humoral and hormonal balance.
Kidneysreact almost immediately to any change in the amount of systemic water and its ingredients. What is unnecessary or excessively they remove, and what is needed either in deficiency they retain or absorb back. Proper kidney function ensures optimal conditions for the work of all organs and tissues in the body.
When the kidneys are sick
Kidney diseases are a very diverse group of diseases of various etiology and clinical picture. They occur more often than is commonly believed. In their course, successive nephrons are turned off, the functions of which are taken over by the others. This, in turn, leads to their excessive exploitation and further shutdowns.
Kidney diseases can be caused by both primary diseases of this organ and their damage in the course of other diseases.
Primary kidney disease can be divided into glomerular and interstitial. In the first case, these are primarily acute and chronic inflammations. They are most often caused by bacterial infections and autoimmune processes. In turn, interstitial diseases (formerly referred to as pyelonephritis) are caused by infectious or toxic agents. Damaging factors can also be deposits (so-called stones) precipitating in the urine and depositing in the renal pelvis or - less frequently - in the tubular wallrenal function.
Another common kidney disease is polycystic kidney disease, which is the replacement of renal parenchyma with cysts that form spontaneously. Cancers of the kidneys and urinary system constitute a separate group.
Secondary kidney damage accompanies many diseases, incl. diabetes (especially type 2), systemic diseases (e.g. visceral lupus), rheumatological and neoplastic diseases from outside the urinary system, as well as chronic inflammatory diseases causing amyloidosis. Particularly noteworthy is the role of the kidneys in arterial hypertension - they can be both the cause and the "victim" of hypertension. Treatment of secondary nephropathy is primarily based on the treatment of the underlying diseases.
Kidney failure
The basic indicator of kidney function is their efficiency. In some conditions, some patients, others all develop failure of this organ, usually determined on the basis of serum creatinine levels.
In case of failure, insufficient blood purification and water removal occur, which leads to an increase in the concentration of unnecessary (waste products) or even harmful (toxins) blood components and fluid overload. The kidneys also cease to fulfill all other regulatory functions. Kidney failure does not only affect this organ, because "contaminated" blood reaches every organ and tissue, disrupting their functions.
There are 2 types of failure: acute and chronic. Acute tends to be more rapid but is reversible. In turn, chronic failure is an irreversible and progressive process, leading to the inevitable loss of function by the kidneys.