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Much research has been done on Chronic Kidney Disease (CKD) by world bodies, yet the cause or causes remain unknown, leading to the term CKDU, “U” being for unknown. In the process, simple facts of physiology and pathology have been overlooked.

I aim to throw a great deal of light on the matter and provide measures to control and eradicate the disease. Many of these insights have not been mentioned by the experts. However, we can help to drop the “U” from CKD. Once the cause is known, the prevention and treatment are easy and inexpensive.

The main reason for CKD in the North Central Province (NCP) is the lack of salt. Excessive sweating during the working day, in the hot dry climate, leads to loss of salt (sodium chloride). According to experts, the world is getting warmer. Sri Lanka is close to the equator and the NCP is one of our hottest areas away from the sea coast. People living in the coastal areas have a cooler climate and consume lots of fish, which is rich in sea salt. Do our NCP farmers consume extra salt in their diet on the advice of health experts, because of excessive sweating? Time was when workers in boiler rooms were given extra salt. The condition is not confined to the NCP alone. It exists elsewhere in the world, under similar climatic conditions.

To the best of my knowledge, none of the experts has mentioned the following, all of which will support my cause. These are:
1. The importance of consuming extra salt, preferably sea salt, which is found in abundance in Sri Lanka: Nephrologists and other medical specialists all advocate a low salt diet, even for these farmers. The World Health Organization advices one level teaspoonful of salt, on the recommendation of medical experts.

2. The destructive part played by very low potassium levels on the tubules of the kidney, leading to a pathological condition called Lower Nephron Nephorsis: Interestingly the site of the damage caused by low potassium is the same site that is damaged by heavy metals like cadmium, arsenic, mercury, lead, etc. Hence the confusion. The low potassium state will be discussed below.
3. The low sodium state (from loss through excessive sweating) leads to low osmotic pressure, low blood volume, dehydration, low kidney perfusion, and ultimately to damage and death of the glomeruli, the head of a nephron. Each kidney has a million nephrons. The glomeruli are connected to the tubules, which do the important work of conserving water and the electrolytes of the body, maintaining homeostasis, the Ph and many other functions.

4. Low kidney perfusion leads to the secretion of rennin, a powerful constrictor of arteries. This will result in reduced blood flow to the brain, causing strokes and reduced flow to the heart, resulting in heart attacks and reduced flow to the kidneys themselves, leading to further damage to kidneys and a rise in blood pressure (hypertension). All organs and tissues are affected, by reduced blood flow. Hypertension leads to an increase in non-communicable disease (NCD).

5. To conserve sodium, another hormone called aldosterone is secreted by the adrenal glands. While conserving sodium, aldosterone dumps potassium via the kidneys, compounding the damage done to the tubules of the kidney. Excellent medicines are available to combat the ill effects of both rennin and aldosterone. They are inexpensive, effective and have been used for decades. The right time to use them has to be clinically determined.

6. Why the NCP? Dry hot climate, excessive sweating leading to loss of sodium and not enough replacement of salt will happen anywhere under similar conditions.

7. Reason why CKD takes 20-40 years to develop on average. There are an estimated 100 trillion cells in the body. Seventy percent of the body is made up of water. There is an amazing set of checks and balances under the control of the brain. Most foods have sodium. Farmers also have off-days from work. Sodium may come from dry fish in the diet. The depletion of sodium and its negative imbalance is a very slow process.

8. Medically test the farmers for low blood volume, low osmotic pressure, low blood pressure (in the earlier stages). These are the early markers of CKD. Also check urea creatine, progressive weight loss, serum sodium and potassium levels.

9. The decreased incidence of CKD in women is because they do not work as hard as the men in the fields in the noonday sun.
The genesis of CKD can be easily prevented and halted by adding extra salt in the diet. There is no proof that consuming extra salt leads to hypertension and NCDs. Any extra salt is promptly excreted by the kidneys to maintain the osmotic pressure of the fluids in the body. Extra salt in the diet will bring on the thirst reflex, which will help to drink more water, but also the only way to retain the correct amount of water in the body. If extra salt is retained in the body, we would all bloat up with retained water and eventually bust.

An article in the Harvard Health Letter states: “Without enough salt, all body fluids would lose water causing dehydration, low blood pressure and death.” The cause of death is not explained in this brief article. As mentioned above, the kidneys are very sensitive to low blood pressure and low kidney perfusion. The latter reacts by producing renin to raise blood pressure and kidney flow. The resulting increase in blood pressure leads to an increase in NCDs.

To replace low sodium in the body fluids, potassium leaks out of the 100 trillion cells in the body to maintain the osmotic pressure. Hence the cells lose potassium, leading to malaise and poor quality of life. Potassium loss from heart cells leads to serious irregular heartbeat and sudden death. Sodium and water work in tandem. One or the other cannot go up or down, leaving the other behind. Further support on avoiding a low salt diet comes from an article published by the prestigious New England Journal of Medicine, Boston, USA. It states that “a low salt diet actually increased deaths from strokes and heart attacks.” The reasons are as explained above. Renin and aldosterone are the causative factors. This article was reproduced by the Straits Times of Singapore on 2 September 2013. The pendulum concerning salt in the diet is now swinging in the opposite direction.
Other measures to prevent CKDU are:-

i. Protective clothing. Broad brimmed hats
ii. Keeping away from the hot noonday sun
iii. Use of agricultural tools, instead of manually tilling fields, rotor tillers and harvesters to be used as needed. Money saved by banning fertilizers can be used
iv. Plenty of clean water: 3-4 liters a day
v. Extra salt to taste and more, banishing the idea of extra salt being harmful. The reverse is proving true.
vi. When potassium is going down, add potassium at the right time
vii. Good nutrition with quality protein and fats; 90 grams of each per day
viii. Yearly medical check-ups at first, more frequent in suspected cases
It appears to the author that by giving an increased dose of salt, every other problem will look after itself, to banish the plague of CKD forever. It is simple as that. However, this may take another 10-30 years. But we have common salt to the rescue. Close clinical observation is essential.

Plan of attack
To new entrants to farming — give enough salt and water. This will prevent CKD for life.
At end stage CKD, only renal dialysis and kidney transplant will be of use. During this stage potassium levels go up to high levels and can lead to cardiac failure. Salt and water are also retained and there is no urine output.

In the intermediate stages, treatment will be carried out, depending on the blood tests, which will give warning signs. An expert team of nephrologists and internists will be needed to follow these cases. By the time the blood pressure is seen to be rising, anti-renin and anti-aldosterone drugs may find a place.

(About The Author: Panawalage Francis Noel Perera, MD., qualified with an M.B.B.S. (Ceylon) degree in 1957. After serving the Ceylon Army for five years, he went to England in 1963. There he was successful in the M.R.C.P. (London), M.R.C.P. (Edinburgh) and M.R.C.P. (Glasgow). He also obtained the L.R.C.P. (London), M.R.C.S. (England) and DCH (London). In 1969, he went to the United States where he was successful in the internal medicine and cardio-vascular specialty examinations conducted by the American Board of Internal Medicine. While in the US, he was also successful in the F.R.C.P. (Canada) examination. Dr. Perera lived and worked in the US as an Internist and cardiologist until his retirement in 1999.)