Psychiatric Technician Practice Exam

In patients with diabetes mellitus, polyuria is usually a result of what condition?

1. Fluid retention

2. Glucose overload

3. Decreased blood pressure

4. Increased protein intake

The correct answer is: Glucose overload

Polyuria in patients with diabetes mellitus is primarily caused by glucose overload in the bloodstream, a condition known as hyperglycemia. When blood glucose levels rise above the renal threshold (the level at which the kidneys can no longer reabsorb all the excess glucose), glucose spills over into the urine. This glucose in the urine creates an osmotic effect, leading to increased water loss through urination (polyuria). As the body attempts to eliminate excess glucose, it pulls additional water into the urine, further exacerbating the condition. Consequently, polyuria is a significant symptom of uncontrolled diabetes, especially in cases where blood sugar levels are poorly managed. This phenomenon highlights the body's response to high glucose levels, demonstrating how metabolic conditions can manifest in physical symptoms.