A 32-year-old woman who is thirsty has a urine osmolarity of $950 \mathrm{mOsm} / \mathrm{L}$ and a serum osmolarity of $297 \mathrm{mOsm} / \mathrm{L}$. Which diagnosis is correct?

Question

Quizplus · Accepted Answer

[Chapter 5, VII A 1; Table 5.6; Figure 5.14]. The description is of a normal person who is deprived of water. Serum osmolarity is slightly higher than normal because
insensible water loss is not being replaced by drinking water. The increase in serum osmolarity stimulates (via osmoreceptors in the anterior hypothalamus) the release of antidiuretic hormone (ADH) from the posterior pituitary. $\mathrm{ADH}$ then circulates to the kidney and stimulates water reabsorption from the collecting ducts to concentrate the urine.

A 32-Year-Old Woman Who Is Thirsty Has a Urine Osmolarity 950mOsm/L950 \mathrm{mOsm} / \mathrm{L}950mOsm/L

A 32-Year-Old Woman Who Is Thirsty Has a Urine Osmolarity $950 \mathrm{mOsm} / \mathrm{L}$