Polyuria

Polyuria (increased urine production) -?Increased glucose from the blood accumulates in the kidney tubules, attracting large amounts of water by osmosis. Urine output increases from around 1.8L seen in healthy people to typically over 3L, in those with diabetes. Polyuria is a common reason why undiagnosed patients visit their GP, as it often disrupts sleep.

Glycosuria (sugar in the urine) -?Patients produce urine containing large amounts of glucose. Normally, glucose is reabsorbed from the kidney tubules back into the blood; in diabetes, the amount overwhelms reabsorption mechanisms. The presence of glucose in urine can be checked with urinalysis strips

Polydipsia (increased thirst) -?Producing large amounts of urine rapidly leads to dehydration, triggering thirst that is difficult to satisfy. This is another common reason why people visit their GP

Polyphagia (increased hunger) -?Although there may be large amounts of sugar in the blood, it does not reach the cells to be used as an energy source. Effectively, patients are in a state of starvation, which triggers the release of hunger hormones such as cortisol and ghrelin. Patient’s will experience an increase in their appetite, but many will crave and eat sugary and starchy foods, exacerbating their condition

Ketoacidosis -?With no sugar to fuel metabolism, the body uses other molecules such as proteins and fats. Breaking down fat (lipolysis) leads to the generation of ketones such as acetone, which can be used in metabolism. Ketones are mildly acidic, but reduce blood pH if they accumulate in large amounts, resulting in ketoacidosis. Unless treated quickly, this medical emergency can lead to coma and death; it can present as increased breathing rate (Kussmaul breathing) and a fruity smell on the breath, and in the sweat and urine. It may also manifest as general abdominal pain, decreased appetite and nausea and vomiting?

Weight loss -?The metabolism of fat and protein in diabetes can lead to significant and unintentional weight loss, particularly in type 1 diabetes

Lethargy -?Glucose is the primary energy source for muscles; the lack of glucose uptake leads to fatigue, which is often compounded by sleep interruptions

Visual disturbances -?Blurred vision and ‘black spots’ in the field of view may indicate damage to the lens and retina.