Arginine vasopressin deficiency

Arginine vasopressin deficiency (previously called neurohypophyseal diabetes insipidus) is a disorder of water balance. The body normally balances fluid intake by releasing fluid in urine. However, people with arginine vasopressin deficiency produce an excessive amount of urine (polyuria), which depletes the amount of water in the body. This water loss also leads to excessive thirst (polydipsia).

People with arginine vasopressin deficiency can quickly become dehydrated if they do not drink enough water. Dehydration can cause dizziness and fatigue. Prolonged dehydration can lead to confusion, low blood pressure, seizures, and coma. People with this condition often develop high levels of sodium in the blood (hypernatremia) due to dehydration. Repeated cycles of dehydration can cause long-term health problems, particularly in children. 

Arginine vasopressin deficiency can be either acquired or familial. The acquired form occurs when the brain is damaged due to head injuries, brain tumors, or other events, and this form can occur at any time during life. The familial form is caused by genetic changes; its signs and symptoms usually become apparent in childhood and worsen over time.

Researchers have recommended using the condition name arginine vasopressin deficiency because the previous name, neurohypophyseal diabetes insipidus, was often confused with a much more common disorder called diabetes mellitus. Arginine vasopressin deficiency and diabetes mellitus are separate disorders with different features, causes, and treatment.