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Diabetes insipidus - nephrogenic
Definition
Nephrogenic diabetes insipidus is a disorder in which a defect in the small tubes (tubules) in the kidneys causes a person to pass a large amount of urine. The tubules normally allow water to be removed from the kidney and returned into the blood, without leaking into the urine.
See also: Diabetes insipidus - central
Alternative Names
Nephrogenic diabetes insipidus; Acquired nephrogenic diabetes insipidus; Congenital diabetes insipidus
Causes
Nephrogenic diabetes insipidus (NDI) occurs when the kidney tubules do not respond to a chemical in the body called antidiuretic hormone (ADH), also called vasopressin. ADH normally tells the kidneys to make the urine more concentrated.
As a result of the defect, the kidneys release an excessive amount of water into the urine, producing a large quantity of very dilute urine. This makes you produce large amounts of urine.
NDI is rare. Congenital diabetes insipidus is present at birth as a result of defect passed down through families that usually affects men. However, women can pass the gene on to their children.
Most commonly, NDI develops because of other reasons. This is called an acquired disorder. Factors that can trigger the acquired form of this condition include:
- Blockage in the urinary tract
- High calcium levels
- Low potassium levels
- Use of certain drugs (lithium, demeclocycline, amphotericin B)
Symptoms
You may have intense or uncontrollable thirst, and crave ice water. You will produce large amounts of urine, usually more than 3 - 15 liters per day.
If you do not drink enough fluids, dehydration can result. Symptoms may include:
- Dry mucous membranes
- Dry skin
- Sunken appearance to eyes
- Sunken fontanelles (soft spot) in infants
Other symptoms that can occur due to inadequate fluids include:
- Fatigue, lethargy
- Headache
- Irritability
- Low body temperature
- Muscle pains
- Rapid heart rate
- Weight loss
Exams and Tests
A physical exam may reveal:
- Low blood pressure
- Rapid pulse
- Shock
- Signs of dehydration
Testing may reveal:
- High serum osmolality
- High urine output, regardless of how many fluids you drink
- Kidneys don't concentrate urine when the person is given ADH
- Low urine osmolality
- Normal or high ADH levels
Other tests that may be done include:
Treatment
The goal of treatment is to control the body's fluid levels. Patients will be given a large amount of fluids. The amount of fluids given should be about equal to the amount of urine produced.
If the condition is due to a certain medication, stopping the medicine may improve symptoms. Never stop taking any medication without first talking to your doctor.
A medicine called hydrochlorothiazide may improve symptoms. This may be used alone or in combination with other medications, including amiloride or indomethacin. Although hydrochlorothiazide is a diuretic (these medications are usually used to increase urine output), in certain cases it can actually reduce urine output for people with NDI .
Outlook (Prognosis)
If a person drinks enough fluids, this condition has no significant effects on the fluid or electrolyte balance of the body. But you will need to drink a lot of water and other fluids.
If the person does not drink enough fluids, high urine output may cause dehydration and high levels of sodium in the blood.
NDI that is present at birth is a long-term condition requiring lifelong treatment.
Possible Complications
- Dilation of the ureters and bladder
- High blood sodium (hypernatremia)
- Severe dehydration
- Shock
When to Contact a Medical Professional
Call your health care provider if you have symptoms of this disorder.
Prevention
There is no known way to prevent congenital nephrogenic diabetes insipidus.
Treating the disorders that can lead to the acquired form of the condition may prevent it from developing in some cases. Medications should only be used under the supervision of the health care provider.
References
Verbalis JG. Posterior pituitary. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 232.
Reviewed By: Shehzad Topiwala, MD, Chief Consultant Endocrinologist, Premier Medical Associates, The Villages, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; David Zieve, MD, MHA, Medical Director, A.D.A.M., Health Solutions, Ebix, Inc.
