Psychogenic polydipsia typically presents with which laboratory pattern?

Psychogenic polydipsia typically presents with which laboratory pattern?

• A. Concentrated urine with high osmolality
• B. Dilute urine around 1.005 with low sodium
• C. Hyperglycemia
• D. Hyperkalemia

Answer: (B)

Excessive water intake in psychogenic polydipsia overwhelms the kidney’s ability to excrete free water, leading to dilutional hyponatremia. To compensate, the kidneys dump water as dilute urine, so urine becomes very dilute with low osmolality and a low specific gravity (around 1.005). The result is hyponatremia alongside a dilute urine pattern, which is the hallmark here. That’s why a dilute urine around 1.005 with low serum sodium best fits psychogenic polydipsia. In contrast, concentrated urine with high osmolality points to ADH activity or dehydration, hyperglycemia causes osmotic diuresis, and hyperkalemia isn’t characteristic of this scenario.

Excessive water intake in psychogenic polydipsia overwhelms the kidney’s ability to excrete free water, leading to dilutional hyponatremia. To compensate, the kidneys dump water as dilute urine, so urine becomes very dilute with low osmolality and a low specific gravity (around 1.005). The result is hyponatremia alongside a dilute urine pattern, which is the hallmark here.

That’s why a dilute urine around 1.005 with low serum sodium best fits psychogenic polydipsia. In contrast, concentrated urine with high osmolality points to ADH activity or dehydration, hyperglycemia causes osmotic diuresis, and hyperkalemia isn’t characteristic of this scenario.