HHS; Hyperglycemic hyperosmolar coma; Nonketotic hyperglycemic hyperosmolar coma (NKHHC); Hyperosmolar nonketotic coma (HONK); Hyperglycemic hyperosmolar non-ketotic state; Diabetes - hyperosmolar
Diabetic hyperglycemic hyperosmolar syndrome (HHS) is a complication of type 2 diabetes. It involves extremely high blood sugar (glucose) level without the presence of ketones.
HHS is a condition of:
Buildup of ketones in the body (ketoacidosis) may also occur. But it is unusual and is often mild compared with diabetic ketoacidosis.
HHS is more often seen in people with type 2 diabetes who don't have their diabetes under control. It may also occur in those who have not been diagnosed with diabetes. The condition may be brought on by:
Normally, the kidneys try to make up for a high glucose level in the blood by allowing the extra glucose to leave the body in the urine. But this also causes the body to lose water. If you do not drink enough water, or you drink fluids that contain sugar and keep eating foods with carbohydrates, the kidneys may become overwhelmed. When this occurs, they are no longer able to get rid of the extra glucose. As a result, the glucose level in your blood can become very high.
The loss of water also makes the blood more concentrated than normal. This is called hyperosmolarity. It is a condition in which the blood has a high concentration of salt (sodium), glucose, and other substances. This draws the water out of the body's other organs, including the brain.
Risk factors include:
Symptoms may include any of the following:
Symptoms may get worse over days or weeks.
Other symptoms that may occur with this disease:
The health care provider will examine you and ask about your symptoms and medical history. The exam may show that you have:
Test that may be done include:
Evaluation for possible causes may include:
At the start of treatment, the goal is to correct the water loss. This will improve the blood pressure, urine output, and circulation. Blood sugar will also decrease.
Fluids and potassium will be given through a vein (intravenously). This must be done carefully. High glucose level is treated with insulin given through a vein.
People who develop HHS are often already ill. If not treated right away, seizures, coma, or death may result.
This condition is a medical emergency. Go to the emergency room or call the local emergency number (such as 911) if you develop symptoms of HHS.
Controlling type 2 diabetes and recognizing the early signs of dehydration and infection can help prevent HHS.
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Graber MN. Diabetes and hyperglycemia. In: Adams JG, ed. Emergency Medicine: Clinical Essentials. 2nd ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 162.
Lebovitz HE. Hyperglycemia secondary to nondiabetic conditions and therapies. In: Jameson JL, De Groot LJ, de Kretser DM, et al, eds. Endocrinology: Adult and Pediatric. 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 42.
Last reviewed on: 2/3/2016
Reviewed by: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.