Neurogenic diabetes insipidus | |
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Synonyms | central diabetes insipidus; pituitary diabetes insipidus; neurohypophyseal diabetes insipidus; cranial diabetes insipidus; neurogenic diabetes insipidus |
Classification and external resources | |
Specialty | endocrinology |
ICD-10 | E23.2 |
ICD-9-CM | 253.5 |
MeSH | D020790 |
Central diabetes insipidus, also called neurogenic diabetes insipidus, is a type of diabetes insipidus due to a lack of vasopressin (ADH) production in the brain. Vasopressin acts to increase the volume of blood (intravascularly), and decrease the volume of urine produced. Therefore, a lack of it causes increased urine production and volume depletion.
It is also known as neurohypophyseal diabetes insipidus, referring to the posterior pituitary (neurohypophysis), which is supplied by the hypothalamus in the brain. This condition has only polyuria in common with diabetes and although not mutually exclusive, with most typical cases, the name diabetes insipidus is a misleading misnomer. A better name might be "hypothalamic-neurohypophyseal ADH deficiency".
In at least 25% of cases (the most commonly occurring classification), neurogenic diabetes insipidus is of unknown cause, meaning that the lack of vasopressin production arose from an unknown cause. It is also due to damage of the hypothalamus, pituitary stalk, posterior pituitary, and can arise from head trauma.
The lack of vasopressin production usually results from some sort of damage to the pituitary gland. It may be caused due to damage to the brain caused by:
Vasopressin is released by the posterior pituitary, but unlike most other pituitary hormones, vasopressin is produced in the hypothalamus. Neurogenic diabetes insipidus can be a failure of production at the hypothalamus, or a failure of release at the pituitary.
The most rare form of central DI is familial neurogenic diabetes insipidus. This form of DI is due to an inherited mutation of the arginine vasopressin-neurophysin II (AVP-NPII) gene, inherited in an autosomal dominant manner. At one point, only 45 families worldwide were known to possess this genetic trait. It is now more widely recognized, although the precise number of people affected with this form of DI is unknown at the present time.