What is the main characteristic of DKA compared to HHS?

The main characteristic distinguishing Diabetic Ketoacidosis (DKA) from Hyperglycemic Hyperosmolar State (HHS) is the speed of onset. HHS tends to develop more gradually than DKA. This slower progression in HHS is often due to the presence of some insulin, which typically prevents the rapid breakdown of fat and subsequent production of ketones; thus, HHS evolves over days to weeks, while DKA can present more acutely within hours.

In DKA, the process is compounded by the absence of sufficient insulin, leading to a rapid increase in blood glucose and the formation of ketones, which directly causes metabolic acidosis. As a result, patients with DKA often present with more immediate symptoms compared to those with HHS, contributing to the crucial difference in their rates of onset. The factors surrounding hydration status, glucose levels, and the presence of ketoacidosis further clarify the distinctions between these two entities, but the primary differentiation lies in the rate at which they develop.