Q: Hi Doc, is there something like Diabetes Insipidus and what causes it?
A: There is something like Diabetes Insipidus and before you ask…no, it’s not related to Diabetes Mellitus 😀
Normally, the kidneys remove excess fluids in the bloodstream and store this temporarily as urine in the bladder prior to urination. This process maintains the fluid balance in the body as thirst is triggered when there is loss of body fluids eg through sweating and urination is triggered in instances where there is excess body fluids. In the first instance, the body conserves fluids and makes less urine. This process is regulated by a hormone called the Anti-Diuretic Hormone (ADH) which is released when there is dehydration which causes the body to conserve fluids and the kidneys to release water back into the blood stream. This causes urine to become more concentrated.
In Diabetes Insipidus (DI), a rare disease condition in which one always feels thirsty even after drinking lots of water and the person produces large quantities of urine, there is an imbalance of water in the body with excretion of large amounts of urine…up to 5 times the normal output of urine in extreme cases. This will present as frequent urination, especially at night and bedwetting.
There are different types of Diabetes Insipidus:
- Central DI, in which there is damage to the gland (pituitary gland) that produces the ADH
- Gestational DI, which is rare but could occur in pregnancy and in this case, an enzyme produced by the placenta destroys ADH in the mother
- Nephrogenic DI, in which the kidneys are unable to excrete or reabsorb water as needed. This can be caused by some medications and can also be present at birth. In the latter case, the cause is genetic. It also affects more males than females. So, check with your baby’s doctor if he urinates more than 10 times a day.
- Primary polydipsia, in which the problem is excessive intake of water which dilutes
Treatment depends on the type of DI:
For Central DI, treatment is with a synthetic (artificial) hormone, desmopressin
For Gestational DI, treatment is also with desmopressin but where it is caused by an altered thirst mechanism, this is not needed.
For Nephrogenic DI, low salt diet and drinking sufficient amounts of water may be all the treatement needed. If medications are the cause, you will need to stop these.
For primary polydipsia, treatment is simple. Reduce fluid intake.
I hope this helps.
Have a great evening everyone J