Urine Analysis
- It is easier to collect a urine sample from someone than a blood sample
- Simple tests on urine can give early indications of health problems
- For example, the presence of glucose and ketones in urine indicates that a person may have diabetes
- If blood glucose concentration increases above a certain value, known as the renal threshold, not all of the glucose is reabsorbed from the filtrate in the proximal convoluted tubule of the kidney and some will be present in the urine
- The presence of protein in the urine indicates that there is something wrong with the kidneys
- Most protein molecules are too large to be filtered
- Some protein molecules are filtered but then reabsorbed by endocytosis in the proximal convoluted tubule, then broken down and the amino acids absorbed into the blood
- A large quantity or the long-term presence of protein in the urine indicates that there may be a kidney infection or a disease affecting the glomeruli
