Diabetes Insipidus

Diabetes insipidus causes frequent urination.

*Diabetes insipidus facts Medically Edited by: Melissa Conrad Stöppler, MD

• Diabetes insipidus is not related to diabetes mellitus (type 1 and type 2 diabetes).
• Diabetes insipidus is caused by problems related to the antidiuretic hormone (ADH) or its receptor and causes frequent urination.
• There are four types of diabetes insipidus; 1) central diabetes insipidus, 2) nephrogenic diabetes insipidus, 3) dipsogenic diabetes insipidus, and 4) gestational diabetes insipidus.
• The most common symptom of diabetes insipidus is frequent urination.
• The diagnosis for diabetes insipidus is based on a series of tests (for example, urinalysis and fluid deprivation test).
• The treatment for diabetes insipidus depends on the type of diabetes insipidus.
• Diabetes can lead to chronic kidney disease.
• Diabetes is the most common cause of kidney failure in the US.

Nephrogenic diabetes insipidus is a disorder of water balance. The body normally balances fluid intake with the excretion of fluid in urine. However, people with nephrogenic diabetes insipidus produce too much urine (polyuria), which causes them to be excessively thirsty (polydipsia). Affected individuals can quickly become dehydrated if they do not drink enough water, especially in hot weather or when they are sick.

Nephrogenic diabetes insipidus can be either acquired or hereditary. The acquired form is brought on by certain drugs and chronic diseases and can occur at any time during life. The hereditary form is caused by genetic mutations, and its signs and symptoms usually become apparent within the first few months of life.

Infants with hereditary nephrogenic diabetes insipidus may eat poorly and fail to gain weight and grow at the expected rate (failure to thrive). They may also be irritable and experience fevers, diarrhea, and vomiting. Recurrent episodes of dehydration can lead to slow growth and delayed development. If the condition is not well-managed, over time it can damage the bladder and kidneys leading to pain, infections, and kidney failure. With appropriate treatment, affected individuals usually have few complications and a normal lifespan.

Nephrogenic diabetes insipidus should not be confused with diabetes mellitus, which is much more common. Diabetes mellitus is characterized by high blood sugar levels resulting from a shortage of the hormone insulin or an insensitivity to this hormone. Although nephrogenic diabetes insipidus and diabetes mellitus have some features in common, they are separate disorders with different causes.

When nephrogenic diabetes insipidus results from mutations in the AVPR2 gene, the condition has an X-linked recessive pattern of inheritance. The AVPR2 gene is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation usually has to occur in both copies of the gene to cause the disorder. However, some females who carry a single mutated copy of the AVPR2 gene have features of nephrogenic diabetes insipidus, including polyuria and polydipsia. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.

When nephrogenic diabetes insipidus is caused by mutations in the AQP2 gene, it can have either an autosomal recessive or, less commonly, an autosomal dominant pattern of inheritance. In autosomal recessive inheritance, both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. In autosomal dominant inheritance, one mutated copy of the AQP2 gene in each cell is sufficient to cause the disorder.

A healthcare professional can diagnose a person with diabetes insipidus based on;

• medical and family history
• physical exam
• urinalysis
• blood tests
• fluid deprivation test
• magnetic resonance imaging (MRI)

Medical and Family History

Taking a medical and family history can help a health care provider diagnose diabetes insipidus. A health care provider will ask the patient to review his or her symptoms and ask whether the patient's family has a history of diabetes insipidus or its symptoms.

Physical Exam

A physical exam can help diagnose diabetes insipidus. During a physical exam, a health care provider usually examines the patient's skin and appearance, checking for signs of dehydration.

Urinalysis

Urinalysis tests a urine sample. A patient collects the urine sample in a special container at home, in a health care provider's office, or at a commercial facility. A health care provider tests the sample in the same location or sends it to a lab for analysis. The test can show whether the urine is dilute or concentrated. The test can also show the presence of glucose, which can distinguish between diabetes insipidus and diabetes mellitus. The health care provider may also have the patient collect urine in a special container over a 24-hour period to measure the total amount of urine produced by the kidneys.

Blood Tests

A blood test involves drawing a patient's blood at a health care provider’s office or a commercial facility and sending the sample to a lab for analysis. The blood test measures sodium levels, which can help diagnose diabetes insipidus and in some cases determine the type.

Fluid Deprivation Test

A fluid deprivation test measures changes in a patient’s body weight and urine concentration after restricting liquid intake. A health care provider can perform two types of fluid deprivation tests:

A short form of the deprivation test. A health care provider instructs the patient to stop drinking all liquids for a specific period of time, usually during dinner. The next morning, the patient will collect a urine sample at home. The patient then returns the urine sample to his or her health care provider or takes it to a lab where a technician measures the concentration of the urine sample.

A formal fluid deprivation test. A health care provider performs this test in a hospital to continuously monitor the patient for signs of dehydration. Patients do not need anesthesia. A health care provider weighs the patient and analyzes a urine sample. The health care provider repeats the tests and measures the patient's blood pressure every 1 to 2 hours until one of the following happens:

• The patient's blood pressure drops too low or the patient has a rapid heartbeat when standing.
• The patient loses 5 percent or more of his or her initial body weight.
• Urine concentration increases only slightly in two to three consecutive measurements.

At the end of the test, a healthcare provider will compare the patient's blood sodium, vasopressin levels, and urine concentration to determine whether the patient has diabetes insipidus. Sometimes, the health care provider may administer medications during the test to see if they increase a patient's urine concentration. In other cases, the health care provider may give the patient a concentrated sodium solution intravenously at the end of the test to increase the patient's blood sodium level and determine if he or she has diabetes insipidus.

Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is a test that takes pictures of the body's internal organs and soft tissues without using x-rays. A specially trained technician performs the procedure in an outpatient center or a hospital, and a radiologist, a doctor who specializes in medical imaging who interprets the images. A patient does not need anesthesia, although people with a fear of confined spaces may receive light sedation. An MRI may include an injection of a special dye, called contrast medium. With most MRI machines, the person lies on a table that slides into a tunnel-shaped device that may be open ended or closed at one end. Some MRI machines allow the patient to lie in a more open space. MRIs cannot diagnose diabetes insipidus. Instead, an MRI can show if the patient has problems with his or her hypothalamus or pituitary gland or help the health care provider determine if diabetes insipidus is the possible cause of the patient's symptoms.

The primary treatment for diabetes insipidus involves drinking enough liquid to prevent dehydration. A health care provider may refer a person with diabetes insipidus to a nephrologist - a doctor who specializes in treating kidney problems or to an endocrinologist, a doctor who specializes in treating disorders of the hormone-producing glands. Treatment for frequent urination or constant thirst depends on the patient's type of diabetes insipidus:

• Central diabetes insipidus. A synthetic, or man-made, hormone called desmopressin treats central diabetes insipidus. The medication comes as an injection, a nasal spray, or a pill. The medication works by replacing the vasopressin that a patient’s body normally produces. This treatment helps a patient manage symptoms of central diabetes insipidus; however, it does not cure the disease.
• Nephrogenic diabetes insipidus. In some cases, nephrogenic diabetes insipidus goes away after treatment of the cause. For example, switching medications or taking steps to balance the amount of calcium or potassium in the patient’s body may resolve the problem.
• Medications for nephrogenic diabetes insipidus include diuretics, either alone or combined with aspirin or ibuprofen.
• Diuretics. Doctors commonly prescribe diuretics to help patients’ kidneys remove fluid from the body. Paradoxically, in people with nephrogenic diabetes insipidus, a class of diuretics called thiazides reduces urine production and helps patients’ kidneys concentrate urine. Aspirin or ibuprofen also helps reduce urine volume.
• Dipsogenic diabetes insipidus. Researchers have not yet found an effective treatment for dipsogenic diabetes insipidus. People can try sucking on ice chips or sour candies to moisten their mouths and increase saliva flow, which may reduce the desire to drink. For a person who wakes multiple times at night to urinate because of dipsogenic diabetes insipidus, taking a small dose of desmopressin at bedtime may help. Initially, the health care provider will monitor the patient’s blood sodium levels to prevent hyponatremia, or low sodium levels in the blood.
• Gestational diabetes insipidus. A doctor can prescribe desmopressin for women with gestational diabetes insipidus. An expecting mother’s placenta does not destroy desmopressin as it does vasopressin. Most women will not need treatment after delivery.
• Complications. Most people with diabetes insipidus can prevent serious problems and live a normal life if they follow the team of healthcare professionals recommendations and keep their symptoms under control.

Eating, Diet, and Nutrition

Researchers have not found that eating, diet, and nutrition play a role in causing or preventing diabetes insipidus.

ADH-resistant diabetes insipidus, congenital nephrogenic diabetes insipidus, diabetes insipidus renalis, diabetes insipidus, nephrogenic, NDI, vasopressin-resistant diabetes insipidus.

The Diabetes Insipidus Foundation, Inc.
Patient Support and Information
Mary Evans-Lee
3742 Woodland Drive
Columbus, GA 31907
Phone: 706-323-7576
Email: [email protected]
Internet: www.diabetesinsipidus.org

The Diabetes Insipidus and Related Disorders Network
535 Echo Court
Saline, MI 48176-1270
Email: [email protected]
Internet: web.archive.org/web/20021201133912/members.aol.com/ruudh/dipage1.htm?mtbrand=AOL_US

National Organization for Rare Disorders (NORD)
55 Kenosia Avenue
P.O. Box 1968
Danbury, CT 06813-1968
Phone: 1-800-999-6673 (voicemail) or 203-744-0100
Email: [email protected]
Internet: www.rarediseases.org

Nephrogenic Diabetes Insipidus Foundation
Main Street
P.O. Box 1390
Eastsound, WA 98245
Phone: 1-888-376-6343
Fax: 1-888-376-6356
Email: [email protected]
Internet: www.ndif.org