Neurogenic diabetes insipidus
|Neurogenic diabetes insipidus|
|Classification and external resources|
Neurogenic diabetes insipidus, more commonly known as central diabetes insipidus, is due to a lack of vasopressin 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.
In at least 25% of cases (the most commonly occurring classification), neurogenic diabetes insipidus is idiopathic, 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:
- Benign suprasellar tumors (20% of cases)
- Infections (encephalitis, tuberculosis etc.)
- Trauma (17% of cases) or neurosurgery (9% of cases)
- Non-infectious granuloma (sarcoidosis, Hand-Schuller Christian disease etc.)
- Autoimmune - associated with thyroiditis
- Other rare causes which include hemochromatosis and histiocytosis.
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.
There is also an X-linked familial form.
Wolfram Syndrome (also called DIDMOAD) is characterised by DI, diabetes mellitus nerve deafness and optic atrophy.
The disorder is treated with vasopressin analogs such as Desmopressin.
- Chitturi S, Harris M, Thomsett MJ, et al (December 2008). "Utility of AVP gene testing in familial neurohypophyseal diabetes insipidus". Clin. Endocrinol. (Oxf) 69 (6): 926–30. doi:10.1111/j.1365-2265.2008.03303.x. PMID 18494865.
- Lee YW, Lee KW, Ryu JW, et al (2008). "Mutation of Glu78 of the AVP-NPII gene impairs neurophysin as a carrier protein for arginine vasopressin in a family with neurohypophyseal diabetes insipidus". Ann. Clin. Lab. Sci. 38 (1): 12–4. PMID 18316776.
- Diabetes Inspidus. Library of the National Medical Society. 2008 http://www.medical-library.org/journals4a/diabetes_insipidus.htm
- "Central Diabetes Insipidus: Pituitary Gland Disorders: Merck Manual Home Health Handbook". Retrieved 2009-04-04.
- Diabetes Inspidus. The Doctor's Doctor. 2005 http://www.thedoctorsdoctor.com/diseases/diabetes_insipidus.htm
- Familial Neurogenic Diabetes Insipidus: a disease caused by a traffic jam?. The Diabetes Insipidus Foundation. 2006 http://diabetesinsipidus.org/4di_familial.htm