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Kidney

The body has two kidneys, which are bean-shaped organs that filter the blood, produce urine, and play a central role in the body's fluid balance and blood pressure.

Contents

Quick version

What is the kidney?

The kidney is a vital organ in the urinary system. We have two kidneys located on either side of the spine, just above the waist. The kidneys clean the blood of waste products and regulate the body's fluid, salt and acid-base balance. They are also important for the production of hormones that regulate blood pressure and the formation of red blood cells.

Anatomy and location

The kidneys are located in the back of the abdomen, near the lower part of the ribs. Each kidney is about 10–12 cm long and has an inner medulla and an outer cortex where filtration takes place.

Filtration of blood and urine production

Each kidney contains about one million nephrons – small filter units that clean the blood of waste products and excess fluid. The urine that is formed is led via the ureters to the bladder.

Regulation of blood pressure and fluid balance

The kidneys regulate blood pressure through the hormone renin and adjust fluid and electrolyte balance by reabsorbing sodium and water. This affects blood volume and thus the pressure in the vessels.

Hormonal production

The kidneys produce hormones such as erythropoietin (stimulates the formation of red blood cells) and convert vitamin D into its active form, which is important for calcium balance in the body.

Common diseases of the kidneys

The kidneys can be affected by infections, kidney stones, chronic kidney failure, cysts and autoimmune diseases that affect filtration. Regular blood and urine tests can detect these conditions at an early stage.

Relevant symptoms

  • Fatigue and decreased urine output
  • Swelling in the legs and feet
  • Blood in the urine
  • Back pain in the kidneys
  • High blood pressure

Related conditions and diagnoses

Questions and answers

The kidneys purify the blood of waste products, regulate fluid balance and produce hormones that control blood pressure and blood values.

The kidneys are located on either side of the spine in the lower part of the chest, just above the waist. They are partially protected by the ribs.

Symptoms of kidney disease include fatigue, decreased urine output, swelling in the legs, high blood pressure, and sometimes blood in the urine or back pain.

The kidneys' job is to clean the blood, and in kidney failure they are unable to do this properly. It can be acute (sudden) or chronic (long-term).

Smaller stones may pass spontaneously with fluid and pain relief. Larger stones may need to be crushed or surgically removed.

Yes, it is possible to live a normal life with one functioning kidney, this assumes that it is healthy and capable of compensating for the other.

High blood pressure can damage the blood vessels of the kidneys, reducing their ability to filter blood and can lead to kidney failure over time.

Polycystic kidney disease is an inherited disease in which fluid-filled cysts form in the kidneys, which can lead to enlarged kidneys and impaired kidney function.

Kidney problems can be detected through blood tests (creatinine, eGFR), urine tests, and imaging tests such as ultrasound or CT to detect structural changes.

By keeping blood pressure in check, avoiding smoking, drinking enough fluids and having good control over diabetes or other diseases.