Diabetes insipidus is a rare disease of the kidneys that causes an imbalance of water in the body. This imbalance increases thirst and urine output significantly. Healthy individuals will pass an average of one to two quarts of fluid each day, while individuals with diabetes insipidus will pass from three quarts to as many as 16 quarts of fluid in one day.
Diabetes insipidus is not related to diabetes mellitus, a disease of the pancreas that causes blood sugar levels to rise.
Causes of Diabetes Insipidus
The body uses an intricate and delicate system of fluid intake (like drinking water) and fluid outtake (like sweating, urinating, and breathing) in order to achieve correct water balance in the body. The kidneys are two small vital organs, one on either side of the body, that help regulate fluids with the help of certain hormones. One such hormone is vasopressin, which is produced by the hypothalamus (region at the base of the brain) and stored in the pituitary gland (a gland located in the brain, behind the nasal bridge).
When fluid levels are low in the body, the pituitary gland releases more vasopressin, signaling the kidneys to absorb more fluid. This results in lower urine volume. When the body has too much fluid and needs to excrete some, the pituitary gland will release less vasopressin, resulting in increased production of urine.
This balance can become interrupted for a variety of reasons. The type of diabetes insipidus diagnosed will depend on the cause.
- Central diabetes insipidus - Central DI is caused by a disruption in the normal production, storage, and/or release of vasopressin due to damage to the hypothalamus or the pituitary gland. This is the most common form of DI.
- Nephrogenic diabetes insipidus - Nephrogenic DI occurs when the kidneys do not respond normally to vasopressin.
- Dipsogenic diabetes insipidus or primary polydipsia - Dipsogenic DI is caused by a defect in the hypothalamus that disrupts the body’s thirst mechanism.
- Gestational diabetes insipidus - Gestational DI only occurs during pregnancy. This type of DI can develop due to an enzyme that breaks down the vasopressin hormone.
Symptoms of Diabetes Insipidus
The most common and indicative signs of diabetes insipidus are:
- Excessive thirst (polydipsia)
- Passage of an abnormally large amount of urine (polyuria)
- Frequent urination at night (nocturia)
Dehydration is a serious complication of diabetes insipidus that can lead to seizures, brain damage, and even death. It is important to recognize the signs of dehydration:
Babies and young children with diabetes insipidus may present the following signs and symptoms:
- Fussiness and/or inconsolable crying
- Frequent urination
- Excessive thirst
- Dry skin
- Vomiting or diarrhea
- Weight loss
- Delayed growth
If you experience extreme thirst or excessive urination in yourself or your child, make an appointment to see a doctor right away.
What to Expect at Your Appointment
During your appointment, the doctor will ask you questions about symptoms and your family medical history. Your doctor will then perform a physical examination to check for signs of diabetes insipidus, such as dry skin and other signs of dehydration.
If your doctor suspects a diagnosis of DI, he/she will prescribe:
- A urinalysis to check the concentration of the urine. More dilute urine can be an indication of DI. Your doctor may also ask that you collect urine over a 24-hour period in a special container. This will allow your doctor to see how much urine is being produced by the kidneys.
- A blood analysis to measure levels of vasopressin or ADH hormone.
- A water deprivation test during which, under supervision, you will stop drinking fluids so that your doctor can measure the changes in your urine output, your weight, and the concentration of your urine and/or blood. This test helps determine the cause, and therefore the type, of diabetes insipidus.
In some cases, the doctor may prescribe an MRI scan in order to look at the pituitary gland for any abnormalities.
Non-surgical Treatments for Diabetes Insipidus
Depending on the diagnosis, patients may be sent to receive treatment to either:
- A nephrologist - A kidney specialist
- Or an endocrinologist - A physician that specializes in the diagnosis and treatment of disorders of hormone-producing glands
Successful diagnosis and treatment of diabetes insipidus requires thorough, collaborative care from physicians within different specialties. At MedStar Washington Hospital Center, patients have access to the only multidisciplinary pituitary center in the Washington, DC, area.
"With various key specialists interacting closely, it allows for rapid exchange of thoughts and ideas leading to better care for the patients." - Dr. Sharma, Director of Pituitary Endocrinology at the MedStar Pituitary Center
Treatment will depend on the type of DI diagnosed.
- Central diabetes insipidus - Typically treated with a synthetic hormone called desmopressin that aims to safely and effectively decrease urine production. This medication is taken either through an injection, a nasal spray, or an oral tablet.
- Nephrogenic diabetes insipidus - Treatment includes incorporating a low-salt diet into your daily routine and drinking plenty of fluids in order to avoid dehydration.
- Dipsogenic diabetes insipidus or primary polydipsia - Currently, there are no effective treatments for dipsogenic DI. Doctors will recommend decreasing fluid intake and sucking on ice cubes in order to increase saliva production and to relieve the feeling of thirst. Patients who wake up multiple times at night to go to the bathroom may be prescribed a low dose of the synthetic hormone desmopressin to decrease urine output at night.
- Gestational diabetes insipidus - Treatment typically involves a prescription of the synthetic hormone desmopressin.
Surgical Treatment for Diabetes Insipidus and Post-Treatment
There are no surgical treatments for diabetes insipidus.
Outlook and Prognosis for Individuals With Diabetes Insipidus
Outcomes for individuals with diabetes insipidus will depend on the cause of the condition. If treated early and properly, patients will not experience severe health complications due to diabetes insipidus.
To make an appointment, or for more information,
contact us at 844-PITUITARY (748-8482).