A 32-year-old with newly discovered diabetes is brought to the emergency department with polyuria and lethargy. They have been sleeping more than usual.
Initial labs show:
- Plasma glucose: 680 mg/dL
- Potassium 3.7 mEq/L
- Serum osmolality: 335 mOsm/kg
Based on the following labs, which feature most strongly supports a diagnosis of hyperosmolar hyperglycemic state (HHS) rather than diabetes ketoacidosis (DKA)?
- Markedly elevated plasma glucose
- Absence of significant metabolic acidosis
- Out of range potassium level
- Elevated effective serum osmolality
