ABSTRACT
The hyperosmolar hyperglycaemic state is characterized by severe hyperglycaemia (typically a plasma glucose level >35 mmol/L) and hyperosmolality (serum osmolality >340 mosmol/kg) which can be assessed from 2[Na+] + 2[K+] + [urea] + [glucose]. In this case, the serum osmolality works out to be 379 mosmol/kg. He has a mild metabolic acidosis but significant ketoacidosis is not present (pH >7.3 and only a trace of ketones in the urine). This condition mostly occurs in those with type 2 diabetes, in contrast to diabetic ketoacidosis which occurs in type 1 diabetes. However, the distinction is not absolute and up to a third of cases can present with both elements.
