Diabetes Insipidus Diagnosis

The definition of diabetes insipidus is that it causes an individual to pass excessive amounts of urine over the course of the day. Anything above 3 liters of urine in a 24 hour period on a regular basis may qualify for a diabetes insipidus diagnosis. The urine must also be diluted to a certain level to meet diagnostic criteria. Excessive thirst usually accompanies the excessive urination.

There Are 4 Types of Diabetes Insipidus

Diabetes insipidus can strike in one of four different forms. There are two types of this disorder, however, that are more common than others. Central diabetes insipidus is caused by a reduction of the anti-diuretic hormone vasopression, causing the kidneys to continue pulling water out of the body because it is registering an excessive amount. This form is usually caused by an injury or tumor that involves the hypothalamus or the pituitary gland, but surgeries in that area may also cause this disorder.

The other common form of diabetes insipidus is called nephrogenic. This refers to the fact that the kidneys are failing to recognize the hormones that are present in the body. There is enough vasopressin being produced, but the kidneys don’t respond to the hormones at all. The end result is that excessive urination is created and excessive thirst occurs as a result. This may be caused by an injury or may be genetic in nature.

The two uncommon types of diabetes insipidus are gestational and dispogenic. The gestational form of this disorder occurs during a pregnancy and typically resolves itself 4-6 weeks after childbirth, though a few mothers experience long-term effects for several years after the pregnancy. In dispogenic diabetes insipidus, the kidneys, hypothalamus, and pituitary gland are functioning normally. The excessive thirst is a mental creation and excessive fluid intake creates the frequent and diluted urine.

How Is Diabetes Insipidus Diagnosed?

Medical providers often look at diabetes mellitus as the cause of excessive thirst and urination first because of the seriousness of that disease. The symptoms are very similar between it and diabetes insipidus, so the worst case scenario is excluded first. Testing for blood sugar levels and other tests are often used to exclude the more common diabetes mellitus.

If there is good blood sugar control, then medical providers typically move toward a diabetes insipidus diagnosis. To confirm it, a medical provider will typically order a fluid fast for up to 12 hours to determine the status of the excessive urination. With diabetes insipidus, there is always high levels of diluted urine even when there are no incoming fluids. The exception to this would be dipsogenic diabetes insipidus, which fasting will bring the person back toward more normal urination habits.

Urine testings is also part of the diagnostic process. Doctors are interested in seeing what sodium levels are and how balanced an individual’s electrolytes happen to be. This information can then be used to help develop a treatment plan.

After the water fasting period has expired, a dose of desmopressin will typically be administered to determine if it is central or nephrogenic diabetes insipidus. The central version of this disorder will respond to the hormone and reduce urine intake levels, while the nephrogenic version will not respond to the hormones at all. From there, the medical provider will begin developing a treatment plan.

What Happens Next?

Once a medical provider has determined that it is indeed a diabetes insipidus diagnosis, it becomes important to find the cause of the disorder. Some types of this disorder can be forced into remission through hormone therapies or fluid replacement as the body heals from a procedure so that natural hormone production levels can increase. Other causes, such as the presence of a tumor or lesion, can be surgically removed to find relief.

Diabetes insipidus may require a lifetime of medication to be able to keep it under control. The prognosis in all versions of this disorder are considered good as long as there is adequate access to water when it is needed. The greatest danger of diabetes insipidus is the thirst not being met, causing dehydration to occur, and that can create several severe health issues over time.

Diabetes insipidus might seem a little scary when the diagnosis first comes in, but with dietary and lifestyle changes, it can be easily controlled. Speak with your medical provider about your excessive thirst and urination right away so that an early intervention can occur so an effective treatment plan can be developed.