Criteria According to the American Diabetes Association, diagnostic features include: * Plasma glucose level >30 mmol/L (>600 mg/dL) * Serum osmolality >320 mOsm/kg * Profound dehydration, up to an average of 9L (and therefore substantial thirst (polydipsia)) * Serum pH >7.30 * Bicarbonate >15 mEq/L * Small ketonuria (~+ on dipstick) and absent-to-low ketonemia ( 30 mg/dL (increased) * Creatinine > 1.5 mg/dL (increased) Imaging Cranial imaging is not used for diagnosis of this condition. However, if MRI is performed, it may show cortical restricted diffusion with unusual characteristics of reversible T2 hypointensity in the subcortical white matter. Differential diagnosis The major differential diagnosis is diabetic ketoacidosis (DKA). In contrast to DKA, serum glucose levels in HHS are extremely high, usually greater than 40-50 mmol/L (600 mg/dL). Metabolic acidosis is absent or mild. A temporary<unk>  of confusion (delirium) is also more common in HHS than DKA. HHS also tends to affect older people more. DKA may have fruity breath, and rapid and deep breathing. DKA often has serum glucose level greater than 300 mg/dL (HHS is >600 mg/dL). DKA usually occurs in type 1 diabetics whereas HHS is more common in type 2 diabetics. DKA is characterized by a rapid onset, and HHS occurs gradually over a few days. DKA also is characterized by ketosis due to the breakdown of fat for energy. Both DKA and HHS may show symptoms of dehydration, increased thirst, increased urination, increased hunger, weight loss, nausea, vomiting, abdominal pain, blurred vision, headaches, weakness, and low blood pressure with standing.
Hyperosmolar hyperglycemic state
Diabetic ketoacidosis
Exercise-associated hyponatremia
Hypotonic hyponatremia
Isotonic hyponatremia
Ketotic hypoglycemia
Hyperosmolar syndrome
Reactive hypoglycemia