Kidneys are vital to health

Fun facts about the kidney

Each kidney weighs about 4 ounces

Each kidney is approximately the size of your fist

Each kidney contains about 1 million tiny blood filters called nephrons. This roughly comes to about 140 miles of tubules in each kidney.

The nephron is the filtering unit of the kidney. The blood is cleansed as it passes through these millions of nephrons. The newly cleansed blood returns to the bloodstream by way of veins. Waste products and excess fluid passes from the kidney through the ureter and enters the bladder, where it is stored as urine. When the bladder becomes full, urine passes out of the body through the urethra.

Our bodies are always working. Even as we sleep, our cells are breaking down food, oxygen, and water called metabolism to replenish the energy, restore and repair themselves, so the body can function at peak efficiency. As a result of all this work, there are left over compounds called waste products, discharged into the blood.

Some of these waste products are toxic, and it is just one of the many functions of the kidneys to filter the blood and remove toxic waste products. In addition, the kidneys clear medications and other ingested materials that are not needed in the body or removed from the blood so that they do not build up in the body and cause toxicity.

Kidney plays a vital role in the regulation of salt and fluid levels in the body, affecting blood pressure and hydration. The kidneys produce hormones that help control blood pressure.

They also produce a substance called erythropoietin that stimulates the production of red blood cells, which are used to carry oxygen to different parts of the human body.

The kidneys also convert the vitamin D into active form, which is critical in keeping your bones and teeth strong and healthy.

Kidneys balance the levels of the vitamins, minerals, and maintain acid-base status in the body to maintain a homeostatic milieu.

  • Filter blood and remove waste products
  • Balance the fluid levels in the body
  • Produce erythropoietin needed to make red blood cells
  • Produce renin that regulates blood pressure
  • Activate vitamin D that helps to maintain calcium and phosphorus levels in the body
  • Maintain acid-base levels to keep a tight control of pH level in the blood

  • Changes the urination, it is possible a person could be urinating in small amounts or the urine could change in color, could become foamy, there could be blood in the urine.
  • Nausea and vomiting and bad taste in mouth (uremia)
  • Shortness of breath
  • Feeling cold/chilled
  • Lack of concentration
  • Swelling of the legs, ankles, feet, face or hands
  • Fatigue, itching could be seen in late stages of kidney failure.

  • Diabetes mellitus type I and type II
  • Hypertension (high blood pressure)
  • Glomerulonephritis (inflammation of the filtering subunit of the nephron)
  • Congenital kidney diseases/defects
  • Hereditary kidney diseases
  • Kidney stone disease
  • Prostatic hypertrophy, causing obstruction

The optimum way of measuring the kidney function is complex and so is not routinely done in clinical practice. As a surrogate for the Optimal measurement a 24 hour urine collection is done to approximately measure the kidney function. Most of the common tests that are done to measure the kidney function measure the function of both the kidneys. To obtain the function of each kidney your physician uses a radiological test in special circumstances and is not commonly needed in systemic kidney disease.

Routinely your nephrologist measures to blood tests called serum creatinine and BUN that help the physician to determine the abnormalities in kidney function. These 2 tests or part of a panel called comprehensive metabolic panel (CMP), a renal function panel, basic metabolic panel (BMP). Your physician usually orders one of these panels to obtain the values for serum creatinine and BUN. Nowadays most of the laboratories report a calculated measure called eGFR (estimated glomerular filtration rate). This is a calculation of the renal function from the serum creatinine that is obtained from these panels.

Serum creatinine – a waste product of muscle activity
Blood urea nitrogen (BUN) – a waste product of protein breakdown