A28-year-old male complained of abrupt polydipsia and polyuria. blood and urine analyses provided the following results:
fasting blood glucose 93 mg/dl
serum sodium 145 meq/l
serum potassium 2.8 meq/l
urine specifie gravity < 1.005
urine osmolality < 200 mosm/l
urine volume 15 lday
urine glucose 0
water deprivation and hypertonic saline infusion do not cause a significant reduction in the polyuria and concentration of urine. complete water-deprivation results in the following:
urine specific gravity 1.009
urine osmolality 225 mosm/l
however, there is a significant concentration of the urine and a decrease in urinary output following administration of adh.
1. define polydipsia and polyuria.
2. describe the location of the disorder in this individual.
3. why did the water deprivation and hypertonic saline infusion not result in a concentrated urine?
4. a nasal spray containing a synthetic substance was self-administered to treat this condition. what type of compound was present in the nasal spray?
5. discuss the hypothalamic-pituitary-target organ pathway for this individual and indicate the normal and pathophysiological conditions involved.