What are the symptoms of diabetes mellitus?
**Core Concept**
Diabetes mellitus is a group of metabolic disorders characterized by chronic hyperglycemia, resulting from defects in insulin secretion, insulin action, or both. The symptoms of diabetes mellitus are a manifestation of the body's inability to use glucose as an energy source, leading to various metabolic and physiological derangements.
**Why the Correct Answer is Right**
The symptoms of diabetes mellitus are primarily caused by the increased glucose levels in the blood, which lead to an osmotic diuresis, causing polyuria and polydipsia. The hyperglycemia also causes an increase in glucose levels in the blood, leading to glycosuria. Additionally, the increased glucose levels in the blood can cause an increase in ketone production, leading to ketosis. The symptoms of diabetes mellitus include polyuria, polydipsia, polyphagia, weight loss, blurred vision, and fatigue.
**Option A:** Glycosuria is a hallmark of diabetes mellitus, but it is not the only symptom. Glycosuria is a result of the kidneys' inability to reabsorb glucose, leading to its excretion in the urine.
**Option B:** Polyuria is a symptom of diabetes mellitus, but it is not the only symptom. Polyuria is a result of the osmotic diuresis caused by the increased glucose levels in the blood.
**Option C:** Polyphagia is a symptom of diabetes mellitus, but it is not the only symptom. Polyphagia is a result of the body's inability to use glucose as an energy source, leading to increased hunger.
**Option D:** Hypoglycemia is not a symptom of diabetes mellitus. Hypoglycemia is actually a complication of diabetes mellitus treatment, particularly with insulin therapy.
**Clinical Pearl / High-Yield Fact**
The classic symptoms of diabetes mellitus can be remembered using the mnemonic "POLY": Polyuria, Polydipsia, Polyphagia, and Weight Loss.
**Correct Answer:** D. Hypoglycemia is not a symptom of diabetes mellitus.