Central diabetes insipidus is due to a deficiency of antidiuretic hormone (ADH) and therefore its defining characteristic is polyuria. Nephrogenic diabetes insipidus is caused by a failure of the kidney to recognize or respond ADH and therefore also leads to polyuria. Both conditions stem from an inability of the kidneys to reabsorb water. The consequences of polyuria are polydipsia and nocturia-other important characteristics of central diabetes insipidus. A serious complication is a dehydration if the patient is unable to drink enough water to replace the fluids lost.

The origins of central diabetes insipidus (central DI) are varied. Only about ten percent of central DI cases have a genetic background [1]. The pattern of inheritance may be autosomal dominant [2], which is due to the accumulation of hormone precursors toxic to neurons. Autosomal recessive forms are also observed, owing to genetic changes in the arginine vasopressin-neurophysin II gene.

Most of the central DI cases are due to non-genetic effects, such as brain injury, brains tumors, or brain surgery. Thus, a history of such events will suggest a neurogenic, or central origin of the condition as opposed to nephrogenic disease. Idiopathic cases are also fairly common. The disease may be caused by autoimmune and inflammatory conditions. Among tumors associated with central DI is craniopharyngioma, the most common pediatric intracranial tumor. Postoperative central DI may occur after various surgeries; almost 20% of patients undergoing transsphenoidal pituitary adenoma surgery developed central DI, which, in most cases, resolved spontaneously in a little over a week [3]. Of patients with serious head injuries, about 15% developed central DI. The most important risk factors were severe head trauma and penetrating trauma [4].

Central DI may be transient, permanent, or triphasic. The triphasic condition starts with a few days of polyuria, followed by amelioration of the symptoms for another few days (owing to release of stored antidiuretic hormone), and ends with permanent central DI.

The symptoms in infants are less specific than in adults and include irritability, crying, weight loss, and growth delays. Apart from nephrogenic DI, central DI needs to be differentiated from psychogenic polydipsia.

• Fever

  Here, we report on a female infant who presented with fever, convulsions, and polyuria. Examination revealed weight and length below the 3rd centile along with signs of severe dehydration. Fundal examination showed bilateral chorioretinitis. [ncbi.nlm.nih.gov]

  […] liquid per day In severe cases, or if a person can't get enough liquid to drink, central diabetes insipidus can cause: Dehydration Confusion Loss of consciousness Symptoms of central DI in children may be: Low energy Irritability Slow growth Weight loss Fever [webmd.com]

  […] characterized by frequent urination. 0001508 Nocturia 0000017 Polydipsia 0001959 Weight loss 0001824 30%-79% of people have these symptoms Anxiety Excessive, persistent worry and fear 0000739 Depressivity Depression 0000716 Excessive daytime somnolence 0001262 Fever [rarediseases.info.nih.gov]

• Fatigue

  A middle-aged woman who was receiving treatment for Graves' disease suddenly complained of polydipsia, polyuria and general fatigue. Laboratory tests showed hyperthyroidism, hypernatremia, hypoosmolar urine and a decreased plasma vasopressin level. [ncbi.nlm.nih.gov]

  This is especially true for individuals who are dealing with unusual fatigue, muscle pain, headaches, fever, and weight loss. Some people have sunken eyes and blood tests may indicate that there are high sodium levels. [diabetesinsipidus.org]

  Signs of dehydration include: thirst, dry skin, sluggishness, fatigue, dizziness, confusion and nausea. If you are severely dehydrated, you can even experience seizures, permanent brain damage and death. [draxe.com]

• Developmental Delay

  Many of these patients have developmental delays and may be diapered later into childhood, which could make polyuria more difficult to appreciate. [academic.oup.com]

  If left untreated, repeated episodes of dehydration can potentially result in seizures, brain damage, developmental delays, and physical and mental retardation. [rarediseases.org]

• Wound Infection

  In Taiwan, Solanum indicum L. has been used in folk medicine for the treatment of inflammation, toothache, ascites, edema, and wound infection. The plant is rich in solanine, an alkaloidal glycoside. [ncbi.nlm.nih.gov]

• Polydipsia

  Two months after the transplantation, she was admitted for persistent polyuria, polydipsia, and nocturia with urine output of more than 4 L/d. [ncbi.nlm.nih.gov]

  Specifically, other more common causes of polyuria and polydipsia are ruled out. Common rule outs include: diabetes mellitus, chronic kidney disease, hypokalemia, hypercalcemia, and psychogenic polydipsia. [en.wikipedia.org]

• Toothache

  In Taiwan, Solanum indicum L. has been used in folk medicine for the treatment of inflammation, toothache, ascites, edema, and wound infection. The plant is rich in solanine, an alkaloidal glycoside. [ncbi.nlm.nih.gov]

• Subcutaneous Nodule

  Herein, the authors describe a 33-year-old woman with nodular RA who was being treated with methotrexate, sulfasalazine and corticosteroids and presented with subcutaneous nodules simultaneously with aseptic meningitis. [ncbi.nlm.nih.gov]

• Fixed Pupils

  pupils (p 0.04), and a prolonged partial thromboplastin time (p 0.04). [ncbi.nlm.nih.gov]

• Neonate-Onset

  OBJECTIVE: To investigate the clinical outcomes of patients with neonatal-onset CDI or adipsic CDI with hypernatremia. [ncbi.nlm.nih.gov]

• Polyuria

  However, persistent polyuria can cause not only patient discomfort, including polyuria and polydipsia, but also volume depletion that can produce allograft dysfunction. [ncbi.nlm.nih.gov]

• Nocturia

  Two months after the transplantation, she was admitted for persistent polyuria, polydipsia, and nocturia with urine output of more than 4 L/d. [ncbi.nlm.nih.gov]

Laboratory studies should include determination of serum electrolyte and glucose, urinary osmolality with simultaneous plasma osmolality values, and the specific gravity of the urine. A large volume of dilute urine, the osmolality (<300 mOsm/kg) of which is lower than that of plasma, is a strong indication for diabetes insipidus (DI) [5]. A reliable test for the detection of DI is the water deprivation test which needs to be performed under supervision to avoid dangerous dehydration. During the test, healthy people will pass urine with an osmolality significantly higher than the plasma osmolality; urine osmolality does not change much after antidiuretic hormone administration. In patients with DI, the urinary osmolality remains low after water deprivation. It will be raised by antidiuretic hormone administration in central DI, but not in nephrogenic DI [6]. Measurement of antidiuretic hormone levels during the water deprivation test increases the accuracy of diagnosis [7].

Determination of levels of other pituitary hormones is recommended in cases of traumatic head injury [8]. Magnetic resonance imaging (MRI) may aid in the diagnosis of central DI because the hyperintense signal seen in T1-weighted images of a healthy posterior pituitary gland is lost in patients suffering from central DI.

• Streptococcus Pneumoniae

  The occurrence of diabetes insidipus has been previously attributed to Streptococcus pneumoniae (S. pneumoniae) in a handful of patients and only once within the pediatric subpopulation. [ncbi.nlm.nih.gov]

1. Fujiwara TM, Bichet DG. Molecular biology of hereditary diabetes insipidus. J Am Soc Nephrol. 2005;16(10):2836-2346.
2. Hedrich CM1, Zachurzok-Buczynska A, Gawlik A, et al. Autosomal dominant neurohypophyseal diabetes insipidus in two families. Molecular analysis of the vasopressin-neurophysin II gene and functional studies of three missense mutations. Horm Res. 2009;71(2):111-119.
3. Kristof RA, Rother M, Neuloh G, Klingmüller D. Incidence, clinical manifestations, and course of water and electrolyte metabolism disturbances following transsphenoidal pituitary adenoma surgery: a prospective observational study. J Neurosurg. 2009;111(3):555-562.
4. Hadjizacharia P, Beale EO, Inaba K, Chan LS, Demetriades D. Acute diabetes insipidus in severe head injury: a prospective study. J Am Coll Surg. 2008;207(4):477-484.
5. Seckl J, Dunger D. Postoperative diabetes insipidus. BMJ. 1989;298(6665):2-3.
6. Di Iorgi N, Napoli F, Allegri AE, et al. Diabetes insipidus--diagnosis and management. Horm Res Paediatr. 2012;77(2):69-84.
7. Zerbe RL, Robertson GL. A comparison of plasma vasopressin measurements with a standard indirect test in the differential diagnosis of polyuria. N Engl J Med. 1981;24;305(26):1539-1546.
8. Krahulik D, Zapletalova J, Frysak Z, Vaverka M. Dysfunction of hypothalamic-hypophysial axis after traumatic brain injury in adults. J Neurosurg. 2010;113(3):581-584.