From the Guidelines
Diabetes insipidus is a rare disorder characterized by excessive thirst and urination, resulting from either insufficient production of antidiuretic hormone (ADH) or kidney insensitivity to ADH, and requires prompt diagnosis and management to prevent dehydration and electrolyte imbalances. The condition can be classified into central diabetes insipidus, where the hypothalamus or pituitary gland fails to produce sufficient ADH, and nephrogenic diabetes insipidus, where the kidneys are insensitive to ADH 1. According to recent expert consensus statements, the diagnosis of nephrogenic diabetes insipidus is often delayed, and treatment recommendations are limited 1.
Key Characteristics and Diagnosis
The condition is characterized by polyuria, polydipsia, and the risk of hypertonic dehydration, with serum osmolality usually >300 mOsm/kg H2O and urine osmolality <200 mOsm/kg H2O 1. Infants are particularly at risk of dehydration due to their limited access to fluids. The mean age at diagnosis is approximately 4 months, with polyuria, failure to thrive, and signs of dehydration as typical presenting symptoms 1.
Treatment and Management
Treatment for nephrogenic diabetes insipidus may include thiazide diuretics, NSAIDs, or dietary salt restriction to reduce urine output 1. The use of desmopressin (DDAVP), a synthetic form of ADH, is often recommended for central diabetes insipidus, administered as a nasal spray, oral tablet, or injection. Recent recommendations also emphasize the importance of free access to fluid, normal-for-age milk intake, and considering tube feeding in infants and children with repeated episodes of vomiting and dehydration 1.
Follow-up and Emergency Management
Ongoing monitoring and follow-up are crucial, with recommendations including regular urine osmolality checks, urine output monitoring, and growth assessments 1. Patients with nephrogenic diabetes insipidus should also have an emergency plan in place, including a letter explaining their diagnosis and advice on intravenous fluid management, as well as a contact number and a medical alert bracelet or card 1.
Multidisciplinary Care
The management of diabetes insipidus requires a multidisciplinary approach, involving a team of healthcare professionals, including a nephrologist, dietitian, psychologist, social worker, and urologist 1. This team-based approach is essential for providing comprehensive care and addressing the complex needs of patients with this condition.
From the Research
Definition and Characteristics of Diabetes Insipidus
- Diabetes insipidus (DI) is an endocrine condition involving the posterior pituitary peptide hormone, antidiuretic hormone (ADH) 2.
- It is marked by expelling excessive quantities of highly dilute urine, extreme thirst, and craving for cold water 2.
- DI is characterized by hypo-osmotic polyuria secondary to abnormal synthesis, regulation, or renal action of antidiuretic hormone 3.
Classifications of Diabetes Insipidus
- The two main classifications of DI 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 2.
- Two less common classifications include dipsogenic DI, characterized by excessive thirst due to a low osmotic threshold, and gestational DI, characterized by increased concentration of placental vasopressinase during pregnancy 2.
Treatment of Diabetes Insipidus
- Treatment of DI is dependent on the disease classification, but severe complications may arise if not tended to appropriately 2.
- The most common treatment of CDI and gestational DI is the administration of synthetic ADH, desmopressin (DDAVP) 2.
- Nephrogenic treatment, although more challenging, requires discontinuation of medications as well as maintaining a renal-friendly diet to prevent hypernatremia 2.
- Thiazide diuretics can be used to treat both central and nephrogenic subtypes of DI 4, 5.
- Desmopressin can be a viable treatment option for lithium-induced NDI 4.