Hyperosmolar hyperglycemic state (HHS) (previously known as hyperosmolar non-ketotic coma (HONK)) is a serious metabolic derangement that can occur in patients with diabetes mellitus, predominantly those with type 2. While there are no distinct imaging features, it is useful for a radiologist to be familiar with this condition.
It usually occurs in type 2 diabetics who have some concomitant illness that leads to reduced fluid intake. The typical patient is 50-70 years old and there may be a precipitating event such as a stroke, MI, chest/urinary infection or systemic inflammatory response .
Due to a combination of hypovolemia, patients are at increased risk of thromboembolic disease, which may be a presenting complaint or complicate hospital management .
High blood glucose levels lead to severe dehydration, increases in osmolarity (relative concentration of solute) and, in turn, carries a high risk of complications, coma, and death.
Treatment and prognosis
Hyperosmolar hyperglycemic state is common in more elderly diabetic patients and is associated with volume depletion without compensating fluid intake. Principles of management are as follows :
- correction of volume depletion with intravenous fluids
- insulin infusion to correct high blood sugar levels (BSLs)
- rehydration often produces significant reductions in BSLs and HHS patients often require less insulin than DKA patients
- BSL and electrolyte monitoring
- search for precipitating cause
History and etymology
Hyperosmolar hyperglycemic state is thought to have been first described by von Frerichs and Dreschfeld in the 1880s .