Diabetes insipidus is a rare condition where the body cannot retain enough water. It occurs in approximately one in 25,000 people and can affect anyone of any age. It is more common in adults.
Diabetes insipidus is very different from diabetes mellitus, which is often just referred to as diabetes. Diabetes mellitus is far more common and occurs when there is too much glucose (sugar) in the blood. It is possible for someone with diabetes mellitus to also develop diabetes insipidus although this is extremely rare.
What is diabetes insipidus?
The amount of water in the body is regulated by a hormone which is known as antidiuretic hormone (ADH), or vasopressin. ADH is made by a part of the brain called the hypothalamus and is stored just below the brain, in the pituitary gland, until it is needed.
When the amount of water in the body becomes too low, ADH is released from the pituitary gland. This helps to retain water in the body by stopping the kidneys from producing urine.
However, in diabetes insipidus, ADH does not stop the kidneys from producing urine and allows too much water to be passed from the body. This results in symptoms such as needing to pass large quantities of urine often and feeling extremely thirsty all the time.
Types of diabetes insipidus
There are two types of diabetes insipidus:
Cranial diabetes insipidus
Cranial diabetes insipidus occurs when there is not enough ADH in the body to regulate the amount of urine that is produced.
This type of diabetes insipidus is more common than nephrogenic diabetes insipidus and can be caused by damage to the hypothalamus or pituitary gland, such as through an infection, operation, or head injury.
Nephrogenic diabetes insipidus
Nephrogenic diabetes insipidus occurs when there is enough ADH in the body, but the kidneys fail to respond to it. It can run in families or it can be caused by kidney damage.
Diabetes insipidus can be treated by correcting the amount of urine that is produced by the body although the condition usually requires life-long treatment.
Glucose
Glucose (or dextrose) is a type of sugar that is used by the body to produce energy.
Blood
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Brain
The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.
Pituitary gland
The pituitary gland is a pea-sized gland in the centre of the head, which hangs below the brain and produces hormones.
Kidneys
Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.
