What is diabetes mellitus?
Diabetes mellitus is a condition in which the level of glucose (the simplest type of sugar) in the blood is poorly controlled, so that sometimes it rises too high and at other times it falls too low. Both these extremes can have serious consequence, for the diabetic person. Later in this study session we will explain how glucose is normally regulated and how it goes wrong in diabetes. People with diabetes mellitus are usually very thirsty, so they drink a lot of fluids and as a consequence they produce large amounts of urine. There is another type of diabetes, called diabetes insipidus, but it is very rare. Diabetes insipidus shares the name 'diabetes' because it also results in the production of large quantities of urine, but this has nothing to do with how the body manages glucose. This study session will focus only on diabetes mellitus, and from this point that is what we mean when we mention 'diabetes'.
Diabetes mellitus has been known for thousands of years, having been described by the Ancient Egyptians and the Romans. The word 'mellitus' comes from the Latin word for 'honeyed' – meaning 'sweet'.
Diabetes mellitus, therefore, describes a condition that produces 'sweet urine' (Figure 2.1). This production of sweet urine occurs as a result of a high glucose level in the blood, which results in glucose leaking into the urine when the kidneys filter the blood to remove impurities.
Describe a simple way to test urine or a sign of diabetes.
Anyone can test their own urine by urinating into a clean container like a pot or a cup, and leaving the container outside. If ants climb into the container (Figure 2.1), there is probably sugar in the urine. (Did you remember this from your study of the Antenatal Care Module? It was in Study Session 9, Figure 9.14).