Hyperosmolar hyperglycaemic 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 2.
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
HHS is common in more elderly diabetic patients and is associated with volume depletion without a compensating fluid intake. Principles of management are as follows 2:
- 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
HHS is thought to have been first described by von Frerichs and Dreschfeld in the 1880s 1.
- 1. Pasquel FJ, Umpierrez GE. Hyperosmolar hyperglycemic state: a historic review of the clinical presentation, diagnosis, and treatment. Diabetes Care. 2014;37 (11): 3124-31. doi:10.2337/dc14-0984 - Free text at pubmed - Pubmed citation
- 2. Marshall SA, Ruedy J. On Call Principles and Protocols E-Book. Elsevier Health Sciences; 2016 Nov 9.