Diabetic hyperglycemic hyperosmolar syndrome (HHS) is a complication of type 2 diabetes. Hyperosmolar hyperglycemic state is a metabolic complication of diabetes mellitus (DM) characterized by severe hyperglycemia, extreme dehydration,. Hyperosmolar hyperglycemic syndrome (HHS) is a clinical condition that arises from a complication of diabetes mellitus. Hyperosmolar hyperglycemic state (HHS) is 1 of 2 serious metabolic. Diabetic hyperosmolar (hi-pur-oz-MOE-lur) syndrome is a serious condition caused by extremely high blood sugar levels. What is hyperosmolar hyperglycemic syndrome (HHS)? · Diabetic HHS.