|Spacefilling 3D model of arginine vasopressin hormone |
called shortly - (AVP).
Nephrogenic Diabetes Insipidus – The ‘Lesser’ Known Type of Diabetes
Ever seen jelly beans swell in water? Well, your kidneys too are designed to soak in as much water as they can, filter it and extract every last ounce of nutrient in the urine. However, this water needs to be retained within the kidney and Nephrogenic Diabetes Insipidus (NDI) prohibits the kidneys from acting like the body’s dam. Instead, you end up urinating every couple of hours, and craving ice cold water throughout the day.
What Is Nephrogenic Diabetes Insipidus?
First things first; Nephrogenic diabetes insipidus is in no way related to the diabetes that you commonly know of! In fact, the term diabetes merely defines a symptom where the patient feels like urinating more often, while insipidus roughly means tasteless. Therefore, the term diabetes insipidus (DI) refers to a condition where the patient experiences polyurea, characterized by an absence of any glucose in it, thus differentiating it from the ‘other’ form of diabetes caused due to insulin deficiency.
Nephrogenic DI is essentially a condition of the kidneys, typified by its’ inability to respond to a special hormone called argenine vasopressin or AVP. Simply put, your kidneys strive to use as little water as possible to remove as much toxic chemicals from the body. This is primarily achieved by functional units called nephrons, present in the kidneys. The use of water to create soluble urine in the nephron is stimulated by the hormone AVP.
However, this functionality is impaired in individuals suffering from nephrogenic DI and as a result; a lot of the water from the body gets flushed out through excessive urination. This in turn creates a short supply of water in the body, thus giving rise to a number of other associative conditions.
What Factors Cause NDI?
Nephrogenic DI may either be inherited or acquired. Inherited NDI is a result of faulty genetic code being passed down through generations. While it is mainly the mother who passes the gene onto her children, its effects in the form of NDI is seen to affect men in the family.
The relations of the viscera and large vessels of the abdomen.
(Seen from behind, the last thoracic vertebra being well raised.)
The kidneys are colored.
On the other hand, acquired NDI can happen to both men and women over a period of time and it can be triggered by factors such as high calcium levels, low potassium levels or owing to blockage in the urinary tract. Even certain prescription drugs taken over a period of time can cause the kidney disorder to appear in the individual.
Symptoms of NDI
If you have NDI, then you are bound to produce a large volume of urine every day. In some cases, this urine volume can be as much as 15 liters per day. Therefore, the main symptom will be thirst – unquenchable and often intense, characterized by a craving for cold water.
However, much of the NDI symptoms actually begin to show when you do not drink enough fluids and therefore suffer from dehydration. The symptoms in such cases will result in dry skin, dryness felt in mucous membranes, eyes sunken into the eye sockets, headache, fatigue, irritability, muscle pains, weight loss and rapid heart rate.
Diagnosis Of NDI
Doctors check for four important factors to make their NDI diagnosis. These include urine volume, urinary concentration (ratio of the water content to the actual solutes in them), plasma concentration and measurement of AVP hormone in the plasma. However, the gold standard with respect to testing for NDI is water deprivation test.
Treatment Of NDI
When treating nephrogenic diabetes insipidus, the final goal for any doctor is to bring some amount of control on the water being lost through excessive urination. Therefore, fluid administration becomes the first line of treatment. Ideally, the fluid intake should equal the amount of water being discharged from the body in the form of urine. As for medications, hydrochlorothiazide, indomethacin and amiloride may be used for treating NDI.