Neurogenic diabetes insipidus, more commonly known as central diabetes insipidus

Diabetes insipidus

Diabetes insipidus is a condition characterized by excessive thirst and excretion of large amounts of severely diluted urine, with reduction of fluid intake having no effect on the concentration of the urine. There are several different types of DI, each with a different cause...

, is due to a lack of vasopressin

Vasopressin

Arginine vasopressin , also known as vasopressin, argipressin or antidiuretic hormone , is a neurohypophysial hormone found in most mammals, including humans. Vasopressin is a peptide hormone that controls the reabsorption of molecules in the tubules of the kidneys by affecting the tissue's...

 production in the brain. Vasopressin acts to increases the volume of blood (intravascularly) and, decreases the volume of urine produced therefore a lack of it causes increased urine production and dehydration.

It is also known as "neurohypophyseal diabetes insipidus".

Idiopathic

In at least twenty-five percent of cases (the most commonly occurring classification), neurogenic diabetes insipidus is idiopathic

Idiopathic

Idiopathic is an adjective used primarily in medicine meaning arising spontaneously or from an obscure or unknown cause. From Greek ἴδιος, idios + πάθος, pathos , it means approximately "a disease of its own kind". It is technically a term from nosology, the classification of disease...

, 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.

Acquired

The lack of vasopressin production usually results from some sort of damage to the pituitary gland

Pituitary gland

In vertebrate anatomy the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing 0.5 g , in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in a small, bony cavity covered by a dural fold...

. The damage to the brain could have been caused by a benign tumor (20 percent of cases), trauma (17 percent of cases), neurosurgery (9 percent of cases) or some rather rare causes which include hemochromatosis, sarcoidosis

Sarcoidosis

Sarcoidosis , also called sarcoid, Besnier-Boeck disease or Besnier-Boeck-Schaumann disease, is a disease in which abnormal collections of chronic inflammatory cells form as nodules in multiple organs. The cause of sarcoidosis is unknown...

, and histiocytosis

Histiocytosis

In medicine, histiocytosis refers to an excessive number of histiocytes, , and is typically used to refer to a group of rare diseases which share this as a characteristic...

.

Vasopressin is released by the posterior pituitary

Posterior pituitary

The posterior pituitary comprises the posterior lobe of the pituitary gland and is part of the endocrine system. Despite its name, the posterior pituitary gland is not a gland, per se; rather, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior...

, but unlike most other pituitary hormones, vasopressin is produced in the hypothalamus

Hypothalamus

The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...

. Neurogenic diabetes insipidus can be a failure of production at the hypothalamus, or a failure of release at the pituitary.

Genetic

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.