What do the kidneys do?
The kidneys are the main organs of the urinary system, which is essentially the body’s plumbing system. The kidneys remove all waste substances and extra water in the form of urine, by filtering the blood. There are two kidneys each located on either side of the spine, which are bean-shaped organs about the same size as a fist. Although you are born with two kidneys, only one healthy kidney is needed for a normal life.
Each kidney is encased in a fatty cushion, known as perinephric fat, with fibrous tissue outside the fat. The kidney’s main job is to filter the blood through tiny tube-like structures or units called nephrons. With each kidney has around 1 million nephrons although this is variable.
More functions of the kidneys
The kidneys remove waste and extra fluid, by acting as your body’s filter. The kidneys filter 200 quarts of blood each day, which creates one to two quarts of urine. Your body’s urine is made up of waste and extra fluid, preventing a build-up of waste and fluid which keeps your body healthy.
The kidneys also control blood pressure. In order to work properly, the kidneys need pressure from the body. However, this pressure can vary as kidneys can force a higher pressure if it seems to low, or try to reduce the pressure if it seems too high. The kidneys do this by controlling the fluid levels in the body and producing the hormones that cause the blood vessels to contract.
Red blood cells are also made by the kidneys. The kidneys produce a hormone called erythropoietin, which instructs bone marrow to make red blood cells. Red blood cells transport oxygen from your lungs to the rest of your body.
The kidneys also keep bones healthy. The kidneys produce a form of Vitamin D, which the body needs to absorb calcium and phosphorus. The kidney also balances the calcium and phosphorus levels in your body, ensuring you get the correct amount.
The kidneys also control the PH levels in the body. The food you consume contains different levels of acid, so the kidneys balance the PH of the body by adjusting the right amounts of acid in your body.
The different types of kidney disease
There are several types of kidney diseases. Although kidneys could be defective at birth, it is also common to acquire kidney diseases during infancy, childhood or in adulthood. It is also possible to develop kidney disease due to conditions in other parts of the body, such as diabetes.
- Inherited Polycystic kidneys
- Infections: Pyelonephritis
- Inflammation: Glomerulonephritis
- Kidney tumors: Benign and malignant
- Obstructive: Due to obstruction of the flow of urine.
- Reflux: Scarring of the kidney due to backflow of the urine
- Kidney stones
- Systemic diseases: Diabetes, high blood pressure (Hypertension)
kidney disease symptoms
Although there aren’t any specific symptoms of kidney disease, there are a number of symptoms that may develop if kidney disease isn’t picked up or worsen despite treatment.
These symptoms include:
- Increased frequency day and/or night.
- Discomfort or pain while passing urine.
- Blood in the urine which may be visible or non-visible.
- Swelling or puffiness of the face particularly around the eyes.
- Swelling around ankles due to fluid retention.
- Loin pain (back pain).
- Foamy urine.
- Feeling tired, and unwell with loss of appetite.
- Shortness of breath.
- Feeling sick.
Testing for Kidney Disease
There are several tests that can be performed to test for kidney disease. These include:
Taking a small blood sample to check the levels of creatinine, urea and electrolytes. This allows the doctor to examine the general state of the kidneys. A urine examination can also be performed to test the colour of urine and its contents, such as sugar, protein, red blood cells, white blood cells and bacteria.
Kidney diseases tests can also be performed by Computerised Tomography (CT) Urography. This involves a taking series of pictures of the kidneys, ureters, and bladder to find out if cancer is present in these organs. A contrast dye is injected into a vein and as the dye moves through the kidneys, ureters, and bladder, the radiology doctor can carefully examine these organs for any abnormality. MRI scans can also be used to take to detailed pictures of areas inside the body for examination.
Biopsies are also used to test for Kidney disease. The removal of cells or tissues that can be viewed under a microscope by a pathologist to check for signs of kidney cancer. However, in most cases, a biopsy is not necessary as the images in CT or MRI scan are sufficient to make a diagnosis of testing kidney cancer.
Kidney disease prevention
Common risk factors for kidney disease are diabetes, high blood pressure, family history of kidney problems. As well as obesity and smoking. To keep kidneys healthy, it is important to drink plenty of water, exercise and eat a healthy diet. If you suffer from diabetes or hypertension, you should get appropriate advice and regular check-ups from your GP, to make sure that your kidneys are working well.
If you notice any urinary problems, particularly after the age of 50, it is important to get checked for kidney diseases. It is also possible for some drugs and medications to damage the kidneys, although early detection is very important to prevent further damage.