Diabetes insipidus (DI) is a rare condition in which the kidneys fail to retain water, while diabetes is a condition in which the body does not produce enough insulin or does not respond normally to insulin, causing abnormally high blood sugar (glucose) levels.
Causes of diabetes insipidus
Vasopressin (VP), also known as antidiuretic hormone (ADH), is a hormone produced by the hypothalamus and stored in the hypothalamus that helps regulate the concentration of fluids in the body.
ADH primarily regulates water levels by controlling urine production. When fluid levels in the body are low, ADH is released to conserve water. ADH increases the reabsorption of water in the kidneys. This reduces the amount of urine produced.
In diabetes insipidus, ADH does not properly regulate the amount of water in the body and causes the body to produce and excrete too much urine. This excessive loss of water can lead to electrolyte imbalance.
DI can be acquired or inherited. Common causes of acquired DI include:
- Head injury or trauma.
- Surgery.
- Brain tumor.
- Chronic use of lithium (mood stabilizer).
Less common causes of acquired DI include:
- High blood calcium levels.
- Low blood potassium levels.
- Kidney infection.
- Ureteral obstruction, such as kidney stones.
- Brain infection.
Typical symptoms of diabetes insipidus
DI is defined as the passage of large amounts (more than 3 liters in 24 hours) of dilute urine (less than 300 milliosmoles per kilogram). Healthy adults typically urinate less than 3 liters per day, while people with DI may urinate 5 to 10 times that amount.
Additional symptoms of diabetes insipidus include:
- The amount of urine is very large but has almost no color or odor.
- Need to wake up at night to urinate.
- Bedwetting.
