Symptoms Diagnosing<unk>  can be difficult as there is no set of concrete physical signs that are<unk>  specific. Changes in the brain that are indicative of<unk>  include those of hyperpnea, muscle weakness, insomnia, lethargy, and convulsions (although uncommon except in extreme cases of incredibly rapid rehydration). Patients with a history of brain tumors, or congenital malformations, may have hypothalamic lesions, which could be indicative of<unk> . Some adults with Type A<unk>  are anorexic in addition to the other symptoms. Testing Initial testing for<unk>  involves electrolyte, blood urea nitrogen (BUN) and creatinine levels, serum and urine osmolality, blood hormone levels, like vasopressin (AVP). In patients who have defects in thirst regulation and vasopresin secretion, serum vassopresin levels are low or absent. Measurements of urine electrolytes and osmolality are critical in determining the central, rather than renal, nature of the defect in water homeostasis. In<unk> , the fractional excretion of sodium is less than 1%, unless a coexisting defect in AVP secretion is present. In salt intoxication, the urine sodium concentrations are very high and fractional excretion of sodium is greater than 1%. Initial test results may be suggestive of diabetes insipidus. The circulating AVP levels tend to be high, which indicate an appropriate response of the pituitary to hyperosmolality. Patients may have mild stable elevations of serum sodium concentrations, along with elevations in both BUN and creatinine levels and in the BUN/creatinine ratio. Characteristic Type A Type A (essential hypernatremia syndrome) involves an increase of the level in which solvent molecules can pass through cell membranes (osmotic threshold) for vasopressin release and the activation of the feeling of thirst. This is the most characterized sub-type of<unk> , however there is no known cause for Type A<unk> . There is debate over whether osmoreceptor resetting could lead to the increase in threshold. Other studies have shown that it is the loss of osmoreceptors, not resetting, that cause the change in threshold. Patients with Type A<unk>  can be at risk of seizures if they rapidly re-hydrate or quickly add a significant amount of sodium into their bodies. If not treated, Type A<unk>  could result in both a decrease in the size of the brain and bleeding in the brain. Type B Type B<unk>  occurs when vasopressin responses are at decreased levels in the presence of osmotic stimuli. Although minimal, there is still some secretion of AVP. This type may be due to some elimination of osmoreceptors. Type C Dopamine pathways in the brain. The production of dopamine is concentrated in the Ventral Tegmental Area and the Substantia Nigra. Type C<unk>  (type C osmoreceptor dysfunction) involves complete elimination of osmoreceptors, and as a result have no vasopressin release when there normally would be. Type C is generally the<unk>  type found in patients with<unk>  diabetes insipidus. Type D Type D is the least commonly diagnosed and researched type of<unk> . The AVP release in this subtype occurs with normally functioning levels of osmoregulation.
Adipsia
Polydipsia
Nocturia
Anuria
Dysuria
Oliguria
Aphagia
Polyuria