Today, March 12th, is being celebrated as World Kidney Day. The kidneys -- each person has two of them located just in front of and on either side of the spinal column -- are very vital organs of the human body; nobody can survive without them. They are responsible for filtering out harmful and toxic waste materials from the body and disposing of them through urine formation. Accumulation of toxins happens on a daily basis, as they are the byproducts that arise from metabolizing our food and medications; so it is easy to see how anything that affects the kidneys affects the body as a whole.
Death is the inevitable outcome of kidney damage and failure. If both kidneys are irrevocably damaged, dialysis will have to be undertaken. Transplant is the only other way to save a life. One positive aspect is that because of Nature's abundant generosity in the area of living organisms, a person can quite easily function on just one kidney alone and kidney transplants have helped plenty of patients. The negative aspect of this is that humans in their tendency to try and profit from everything they lay their hands on have exploited many innocent people needing to make ends meet into selling a kidney or even worse stealing it from them; this is a shady aspect of the human life and deplorable.
Death from infectious diseases is set to go down in the future, what with better technologies to combat infectious agents. It is now the impending lifestyle diseases that threaten these delicate organs. Kidney disease that arise out of lifestyle diseases are usually chronic. Chronic means that the disease manifests itself over a long period of time and the injury to the organs compounds until finally the organs fail to function. Symptoms are often minimal in the early stages and easily overlooked, and the condition is detected mostly by accident, during routine blood work. Therefore regular and routine checkups are a must, possibly done every year since these diseases can be easily controlled at an early stage and the onset of kidney damage/failure is postponed if not completely prevented.
How do kidneys function? Basically they contain an inbuilt filtration system which work on a molecular level.
The kidney is composed of numerous tiny units that are called nephrons that house the glomeruli and the tubules, forming a component called Bowman's capsule. There are millions of this in each kidney. Take a look at the image on the bottom right and just imagine the interior of each kidney dotted with millions of copies of this picture, microscopically arranged side by side.
The glomeruli are small blood vessels, barely visible to the naked eye. After the body breaks down food and uses up required energy, the byproducts of digestion of food as well as medication are taken via the kidneys' artery system to these blood vessels.
These blood vessels are entwined with the tubules (Bowman's capsule) and a complicated chemical exchange takes place whereby toxic elements are separated from useful proteins and cells and are sent into the tubules that collects them and thus urine is formed.
The purified blood is then sent back to the body with the useful proteins and glucose that were spared the filtration process. Millions of tubules finally send this urine to the bladder via two tubes, one from each kidney. This is the simplest way to explain such a complicated and amazing process, but it is important to educate yourself on its general working.
The kidneys are not just our filtration system, they release three very important hormones:
Erythropoietin which stimulates the bone marrow to produce red cells;
Renin which regulates blood pressure;
Calcitriol, the active form of vitamin D, which helps calcium absorption from the blood and helps in maintaining normal body chemistry.
It is easy to see how vital and complex this delicate pair of organ is to our very survival.
Chronic renal failure is caused by loss of majority of the functioning nephrons. This eventually leads to a condition called end-stage renal disease, whereby most of the nephrons have been killed due to thickening of walls and eventual blockage of capillaries. Capillaries that help filtration of toxic waster are very very tiny -- microscopic. Therefore any damage to such an intricately delicate system affects kidney function as a whole. Ordinarily, the body is able to repair most injuries. But if injuries accumulate over a long time without giving the body a chance to heal, such as is seen in patients with diabetes or hypertension (the two biggest causes of kidney failure in the world), the kidneys begin to lose function and finally fail. Intensive education and preventive care is crucial to patients with high risk profile. This cannot be emphasized enough.
The occurence and severity of kidney disease in diabetic patients is variable, depending genetics, blood sugar control, and blood pressure. The better the control of blood sugar and BP, the lower are the chances of contracting kidney disease. High glucose levels in the blood cause the kidney to filter too much blood, overloading the filtration system. Frequent urination is one of the major symptoms of diabetes. This overload on the kidney's filtration system eventually causes enough wear and tear to make them leak important proteins and glucose into the urine which would otherwise have been retained in the blood and reused by the body. This is microalbuminuria and glucosuria, which are detected during routine urine testing. This, if left untreated, can progressively get worse with loss of larger proteins, leading to macroalbuminuria, which signals kidney failure. Also the higher level of glucose in the blood makes the person more susceptible to infections which compound the problem.
Once the kidneys fail to function, toxins build up in the body. This is uremia. They need to be removed. This is where artificial replacement of kidneys come in -- dialysis. Blood is filtered and cleaned outside or inside the body by various means, and this must be done more or less on a daily basis. In acute kidney disease, such as a sudden infection, dialysis is temporary until the kidney can heal. In chronic conditions, the kidneys are unable to heal and therefore dialysis is more or less a permanent treatment, unless a transplant is done.
I can only urge my readers to educate themselves by reading up on this subject, especially if they have loved ones who are at risk for chronic renal disease. Hopefully World Kidney Day will spread the word on these amazing organs and help people take better care of themselves.
Note: The above images of the kidneys have been borrowed from bbc.co.uk.