Diabetic Kidney Disease
- Part 1 -

Prof JC Sanasam *

Kidney :: Pix - wikipedia.org

Last week 'World Kidney Day' was observed in all countries across the world. Disorders of the kidney are becoming a topic of serious matter in the health arena at the level of international concern, reported to be more threatening in the Indian scenario, not to leave Manipur at that.

Out of all kidney disorders again the Diabetic Kidney Disease has become the most dreaded one as it can lead to kidney failure, cardiovascular (heart) disease such as cardiovascular stroke (heart attack) and finally death. It is also true that statistically, rather more factually, heart attacks and strokes are much more common when associated with Diabetic Kidney Disease than in ordinary common people.

Understand your kidney and urine

We tend to consider that the stool is much more prominent than urine in matters of regulation of our body. But the fact of the matter is that the urine is much more significant than the stool. The urine is a post-filter direct waste-product of the blood itself whereas the stool is the residual waste-product of the undigested food we ingest. This information itself should be eloquent enough to give the idea of urine's importance in the metabolism (the complex of the chemical and physical process involved in the maintenance of life).

The kidneys are bean-shaped important organs, the size and weight of each is about that of a large orange. The two kidneys lie to the sides of the upper abdomen (the loins), behind the intestines inside the abdomen on either side of the spine.

A large artery (An artery is a flexible pipe through which fresh blood from the heart containing oxygen passes) – the Renal artery - takes blood from the heart to the kidney. The artery divides into many tiny blood vessels (capillaries) throughout the kidney. In the outer part of the kidneys tiny blood vessels cluster together to form structures called glomeruli. Each glomerulus acts like a filter.

The texture of the glomerulus is intricate in such a way that it allows some waste products and water and some salts to pass from the blood into a tiny channel called a tubule whilst keeping blood cells and protein in the bloodstream. Each glomerulus and tubule makes up a nephron, the unit of the filtering mechanism of the kidney. There are about one million nephrons in each kidney.

Whilst passing along the tubule the waste products and water undergo certain complex auto-adjustment in regulating its content. Some amount of water and salts may be absorbed back into the bloodstream depending on how it reads to maintain the ideal levels. Tiny blood vessels next to each tubule enable this 'fine tuning' of the transfer of water and salts between the tubules and the blood.

The liquid that remains at the end of each tubule is called urine. The formation of urine is complete at this stage and is now ready to drain out of the body. This urine drains into larger channels (collecting ducts) which consequently again drain into the renal pelvis (the collecting funnel at the centre of the kidney). From here it then passes down a tube called ureter which goes from each kidney down to the bladder, a cistern like receptacle that lies in the lowermost part of the abdomen. Urine is stored in the bladder until it is passed out when we go to the toilet.

The 'cleaned' (filtered) blood from each kidney collects into a large vein – the renal vein – which takes the blood back towards the heart which would in turn send it to the lungs for further oxygenation and purification before the heart sends it again to the kidney through the renal artery.

The main functions of the kidneys are to: o Filter out waste products from the bloodstream to be passed out in the urine
o Help control blood pressure – partly by the amount of water passed out of the body as urine and partly by making hormones which are involved in blood pressure control
o Make a hormone called erythropoietin which stimulates the bone marrow to make red blood cells which are essential for carrying oxygen.
o Help keep various salts and chemicals in the blood at right level, for example, sodium, potassium, calcium, and phosphate. An imbalance of these electrolytes (salts and chemicals) in the bloodstream can cause serious problems in other parts of the body.

What is Diabetic Kidney Disease

Diabetic Kidney Disease (Diabetic Nephropathy) is a complication that occurs in some people with diabetes as a result of damage to the glomeruli, the filters of the kidneys. Because of this the kidneys 'leak' abnormal amounts of protein from the blood into the urine. The main protein that leaks out from the damaged kidneys is called albumin. In normal healthy kidneys only a tiny amount of albumin is found in the urine. A raised level of albumin in the urine, the kidney unable to harness it is the typical first sign that the kidneys have become damaged by diabetes.

Symptoms of Diabetic Kidney Disease:

When the kidneys do not do their job, toxins can build up in the blood and disorders and discomforts in terms of symptoms will appear in the body:
o Swelling or puffiness. This is called edema and can occur around the eyes, legs, ankles, feet, abdomen and less often in other parts of the body
o Trouble in urinating (either being unable to go, or going more than usual). Sometimes pain or burning can occur with urination. The urine also could be foamy, bloody or dark
o Fatigue, being unable to concentrate, or tiring easily
o Insomnia, inability to sleep or lack of sleep
o Feeling 'winded' or out of breath
o Loss of appetite and/or a metallic taste in the mouth
o Nausea or vomiting
o Inability to keep warm
o Dizziness
o High blood pressure
o Itching or rashes
o Pain mostly in legs and back, especially around the kidney area.

Diabetic kidney disease is divided into two main categories, depending on how much albumin is lost through the kidneys:
o Microalbuminuria: This is when the amount of albumin that leaks into the urine is between 30 and 300 mg per day. It is sometimes called incipient nephropathy
o Proteinuria: This is when the amount of albumin that leaks into the urine is more than 300 mg per day. It is sometimes called macroalbuminuria or overt nephropathy.


To be continued...