The Centenary Celebrations-Insulin and Diabetes.

Most people will know the word diabetes. Few people will not know it has something to do with sugar. Diabetes mellitus is the complete name for the condition, mellitus meaning sweet or honey taste found in the urine. Not to be confused with Diabetes insipidus, a condition of the pituitary gland, the kidney or the Psyche where water cannot be retained by the body and very severe thirst and huge polyuria (passing a huge amount of urine occurs). The condition Diabetes mellitus was known in Egyptian times and in recent times has become so much more prevalent. Alas most people will have a relation with the condition and will be aware that complications can occur such as blindness. Even today with all our new medications and all our new knowledge, still diabetes shortens life span by 10 or so years but this figure is rapidly getting less due to earlier diagnosis and better treatment for high blood sugar, cholesterol and high blood pressure. To go back more than 100 years obese patients who developed diabetes could cure the symptoms which include thirst, passing a lot of urine, tiredness and genital itch by weight reduction and exercise. The reason for this improvement is now known in much more detail than it was then. The hormone insulin which is secreted by the islet cells in the pancreas lowers blood sugar. A deficiency of insulin leads to a rising blood sugar and the high blood sugars are the cause of the thirst. The high blood sugar is no longer able to be contained by the kidney and is secreted in the urine. The high concentration of sugar in the urine pulls out sugar by osmosis, drags with it, water, so the higher the glucose in the blood and urine the more water is pulled through the kidneys which are filters. The increased amount of water thus lost, results in frequency of passing water which is now full of glucose. The loss of water is recognised by the thirst mechanism which gets switched on and being very thirsty the patient with diabetes starts to drink and drink to make up for the loss of water in the urine. Sometimes the patient who might have been keen on lemonade or other sweet drinks just drinks more and more not realising that the drinks are heavily laden with sugar. This results in increasing the blood sugar even higher and even more thirst until the whole system collapses. The patient becomes unconscious very dehydrated and will die unless given intravenous fluids and then insulin. One such lady was a patient of mine. The African lady was so complicated that after she recovered we wrote up her case in one of the medical journals to inform others of the problems we faced and the treatments we gave which resulted in her recovery. Hyperosmolar coma is the name of the condition and thankfully rare. I can of course remember other patients who we were not successful in saving but they are too painful to relate.