If left untreated, diabetes insipidus can cause dehydration and electrolyte imbalance, resulting in excessive thirst and urination. It is a rare condition that affects the balance of fluids in the body. Unlike diabetes mellitus, which causes high blood sugar levels, diabetes insipidus is not related to diabetes mellitus.
ADH, also known as vasopressin, is a hormone that causes diabetes insipidus. The pituitary gland, a small gland at the base of the brain that controls many hormones, stores and releases ADH, which is produced by the hypothalamus, the part of the brain that regulates many bodily functions. As a result of ADH, the kidneys reabsorb water from the filtered blood and return it to the bloodstream, thus regulating urine production and salt levels.
There are four main types of diabetes insipidus, depending on the cause of the ADH problem:
ADH cannot be produced or released enough as a result of damage or disease to the hypothalamus or pituitary gland, which is the most common type of diabetes insipidus. Head injuries, brain tumors, infections, inflammation, surgery, radiation, and genetic disorders can cause this.
In nephrogenic diabetes insipidus, the kidneys do not respond to ADH, even when the level is normal or high. There are several reasons for this, including kidney disease, chronic kidney failure, certain medications, low potassium levels, high calcium levels, and genetic disorders.
A person with dipsogenic diabetes insipidus drinks too much fluid, suppressing the production of ADH. This can be caused by damage to the hypothalamus, mental illness, or certain medications.
It is caused by the placenta producing a substance that breaks down ADH during pregnancy. It usually resolves after delivery, but may require treatment during pregnancy.
The main symptoms of diabetes insipidus are:
Extreme thirst, often with a preference for cold water
Frequent and large amounts of diluted urine, which may be pale or colorless
Nocturia, or waking up at night to urinate
Dehydration, which may cause dry mouth, dry skin, fatigue, dizziness, headache, low blood pressure, rapid heartbeat, weight loss, and confusion
Electrolyte imbalance, which may cause nausea, loss of appetite, muscle cramps, weakness, and seizures
There are several types and severity of diabetes insipidus, as well as fluid intake and output. In some cases, symptoms may be mild or absent, especially if the person drinks enough fluid to compensate for the water loss.
The diagnosis of diabetes insipidus is based on the medical history, physical examination, urine and blood tests, and sometimes imaging tests or genetic tests. Some of the tests that may be done are:
Water deprivation test: This test measures the urine output and concentration, and the blood levels of ADH, sodium, and osmolality (a measure of the concentration of particles in a solution) after several hours of fluid restriction. A person with diabetes insipidus will continue to produce large amounts of diluted urine, and have low ADH and high sodium and osmolality levels.Diagnosing diabetes insipidus requires medical history, physical examination, urine and blood tests, and sometimes imaging tests or genetic tests. Some tests include several hours of fluid restriction. A person with diabetes insipidus will continue to produce large amounts of diluted urine, and have low ADH and high sodium and osmolality levels. The test may also be done with an injection of synthetic ADH (desmopressin) to see if the urine output and concentration change. This can help to distinguish between central and nephrogenic diabetes insipidus.
The urine analysis test examines the color, clarity, specific gravity, pH, glucose, protein, and ketones of the urine, as well as its physical and chemical properties. A person with diabetes insipidus will have clear, colorless, and low specific gravity urine, and there will be no glucose, protein, or ketones.
In blood tests, glucose, sodium, potassium, calcium, creatinine, and osmolality are measured. People with diabetes insipidus may have high glucose, sodium, and osmolality levels, but low potassium and calcium levels. Creatinine is a marker of kidney function, and may be elevated in nephrogenic diabetes insipidus.
This test uses a magnetic field and radio waves to create detailed images of the brain and pituitary gland. It can detect any abnormalities, such as tumors, infections, or injuries that may affect ADH production.
Genetic test: This test analyzes the DNA for any mutations that may cause inherited forms of diabetes insipidus.
Treatment of diabetes insipidus depends on its type and cause, and the severity of the symptoms. The main goals of treatment are to relieve thirst, reduce urine output, prevent dehydration, and correct electrolyte imbalances.
Desmopressin, a synthetic form of ADH, is the most commonly prescribed medication for diabetes insipidus. In the kidneys, it increases water absorption, and in the urine it reduces urine output and concentration. Desmopressin is effective against central and gestational diabetes insipidus, but not against dipsogenic or nephrogenic diabetes insipidus. Among the medications available for diabetes insipidus are thiazide diuretics, which paradoxically decrease urine output by increasing sodium reabsorption in the kidneys, and nonsteroidal anti-inflammatory drugs (NSAIDs), which enhance the kidney's response to ADH. Diabetes insipidus with nephrogenic origin may benefit from these medications, but not diabetes insipidus with central or gestational origin.
A key aspect of diabetes insipidus treatment is avoiding dehydration and electrolyte imbalance by drinking enough fluid. Generally, plain water is preferred, since it contains no calories, sugar, or salt. The amount and type of fluid may vary depending on the type and severity of diabetes insipidus, and the urine output and concentration. In some cases, electrolyte solutions or sports drinks may be recommended to replace lost salts and minerals. Fluid intake should be adjusted according to thirst, urine output, and blood tests.
Dietary modification: Diet for diabetes insipidus should be balanced and healthy, and provide adequate calories, protein, carbohydrates, fat, vitamins, and minerals.
Reduce the intake of salt, as it can increase the urine output and worsen dehydration and electrolyte imbalance.
Dehydration and electrolyte imbalance can be worsened by excessive salt intaken increase the urine output and worsen dehydration and electrolyte imbalance.
Diuretic foods and drinks, such as caffeine, alcohol, and some herbal teas, can increase low potassium levels that may occur due to diabetes insipidus.
Foods high in potassium, such as bananas, oranges, potatoes, and spinach, can help prevent or correct low potassium levels caused by diabetes insipidus.
Consult a dietitian or a doctor for more specific and individualized dietary advice.
It may be possible to improve or cure diabetes insipidus if the underlying cause is treated, such as a tumor, infection, inflammation, or injury. If a tumor affects the pituitary gland or hypothalamus, for instance, surgery, radiation, or medication can be used to remove or shrink it. Diabetes insipidus may be permanently caused by an infection or inflammation of the hypothalamus or pituitary gland that is not treatable with antibiotics or anti-inflammatory drugs.
Due to the fact that diabetes insipidus is often caused by factors outside one's control, such as genetic disorders, head injuries, brain tumors, or infections, there is no known way to prevent it. It is possible, however, to reduce diabetes insipidus' risk or severity by taking the following general measures:
Avoiding head trauma, such as by wearing a helmet when riding a bike or a motorcycle, or a seat belt when driving a car.
Seeking medical attention promptly if there are any signs or symptoms of a brain tumor, such as headaches, vision problems, seizures, or personality changes.
Seeking medical attention promptly if there are any signs or symptoms of a brain infection, such as fever, stiff neck, confusion, or vomiting.
Following the doctor’s instructions and monitoring the blood tests when taking medications that may affect the kidneys, such as lithium, amphotericin B, or demeclocycline.
Following the doctor’s instructions and monitoring the urine output and concentration when taking medications that may affect the ADH production or release, such as chlorpropamide, clofibrate, or carbamazepine.
Drinking enough fluid to prevent dehydration and electrolyte imbalance, especially during hot weather, exercise, or illness.
