**Core Concept**
Non-ketotic hyperosmolar coma (NKHC) is a life-threatening condition characterized by severe hyperglycemia, hyperosmolality, and altered mental status without significant ketosis. It predominantly affects elderly patients with type 2 diabetes mellitus.

**Why the Correct Answer is Right**
NKHC typically presents with severe hyperglycemia (blood glucose levels often > 600 mg/dL), hyperosmolality, and a marked increase in blood osmolality. The absence of significant ketosis in NKHC is due to the limited ability of the liver to produce ketones in the absence of insulin deficiency. This condition is primarily caused by a combination of factors, including dehydration, infection, and the use of certain medications that impair glucose metabolism.

**Why Each Wrong Option is Incorrect**
* **Option A:** Severe hyperglycemia is a hallmark of NKHC, making this option incorrect.
* **Option B:** Hyperosmolality is a key feature of NKHC, making this option incorrect.
* **Option C:** Glycosuria and glucosuria are common in NKHC due to the high blood glucose levels, making this option incorrect.

**Clinical Pearl / High-Yield Fact**
In NKHC, the glucose level often correlates with the degree of hyperosmolality, and the treatment involves aggressive fluid replacement and insulin therapy to rapidly correct the hyperglycemia and hyperosmolality.

**Correct Answer: C. Hyperkalemia**