From the Guidelines
Diabetes insipidus is primarily caused by problems with antidiuretic hormone (ADH), also known as vasopressin, with the two main causes being central diabetes insipidus and nephrogenic diabetes insipidus. The causes of diabetes insipidus can be understood by considering the role of ADH in regulating water balance in the body. Central diabetes insipidus occurs when the hypothalamus or pituitary gland is damaged, resulting in insufficient production or release of ADH, which can be due to head injuries, brain tumors, brain surgery, infections like meningitis, or autoimmune conditions 1.
Causes of Nephrogenic Diabetes Insipidus
Nephrogenic diabetes insipidus happens when the kidneys don't respond properly to ADH, despite normal hormone production. This can be caused by:
- Genetic mutations
- Certain medications (like lithium or tetracyclines)
- Chronic kidney disease
- Hypercalcemia
- Hypokalemia, as noted in the international expert consensus statement on the diagnosis and management of congenital nephrogenic diabetes insipidus 1.
Other Forms of Diabetes Insipidus
Less commonly, gestational diabetes insipidus can occur during pregnancy due to increased metabolism of ADH by the placenta. Primary polydipsia, while not true diabetes insipidus, can mimic its symptoms when excessive fluid intake overwhelms the kidneys' concentrating ability. Understanding these causes is essential for proper diagnosis and treatment, as management strategies differ depending on the underlying mechanism. According to the latest research, the diagnosis and management of diabetes insipidus should be based on the latest clinical practice recommendations, which emphasize the importance of free access to fluid, normal-for-age milk intake, and consideration of tube feeding in infants and children with repeated episodes of vomiting and dehydration 1.
From the Research
Causes of Diabetes Insipidus
- Diabetes insipidus can be caused by two fundamentally different defects: inadequate or impaired secretion of antidiuretic hormone (ADH) from the posterior pituitary gland (neurogenic or central diabetes insipidus) or impaired or insufficient renal response to ADH (nephrogenic diabetes insipidus) 2.
- The two main classifications of diabetes insipidus are central diabetes insipidus (CDI), characterized by a deficiency of the posterior pituitary gland to release ADH, and nephrogenic diabetes insipidus (NDI), characterized by the terminal distal convoluted tubule and collecting duct resistance to ADH 3.
- Central diabetes insipidus results from a deficiency of the hormone arginine vasopressin (AVP) in the pituitary gland or the hypothalamus, whereas nephrogenic diabetes insipidus results from resistance to AVP in the kidneys 4.
- Diabetes insipidus can also be caused by other factors, including:
- Dipsogenic DI, characterized by excessive thirst due to a low osmotic threshold 3.
- Gestational DI, characterized by increased concentration of placental vasopressinase during pregnancy 3.
- Primary polydipsia, which involves excessive intake of large amounts of water despite normal AVP secretion and action 4, 5.
- The etiology of diabetes insipidus is sometimes clear, but in some cases, it can be difficult to distinguish from primary polydipsia 5.