Diabetic hyperglycemic hyperosmolar syndrome
Diabetic hyperglycemic hyperosmolar syndrome (HHS) is a complication of type 2 diabetes. It involves an extremely high blood sugar (glucose) level without the presence of ketones.
Type 2 diabetes
Type 2 diabetes is a lifelong (chronic) disease in which there is a high level of sugar (glucose) in the blood. Type 2 diabetes is the most common f...
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Causes
HHS is a condition of:
- Extremely high blood sugar level
- Extreme lack of water (dehydration)
- Decreased alertness or consciousness (in many cases)
A buildup of ketones in the body (ketoacidosis) may also occur, but it is unusual and is often mild compared with diabetic ketoacidosis.
Diabetic ketoacidosis
Diabetic ketoacidosis (DKA) is a life-threatening problem that affects people with diabetes. It occurs when the body starts breaking down fat at a r...
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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:
- Infection
- Other illness, such as heart attack or stroke
- Medicines that decrease the effect of insulin in the body
- Medicines or conditions that increase fluid loss
- Running out of, or not taking prescribed diabetes medicines
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, you become very dehydrated. When this occurs, the kidneys are no longer able to get rid of the extra glucose. As a result, the glucose level in your blood can become very high, sometimes more than 10 times the normal amount.
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:
-
A stressful event such as infection, heart attack, stroke, or recent surgery
Heart attack
Most heart attacks are caused by a blood clot that blocks one of the coronary arteries. The coronary arteries bring blood and oxygen to the heart. ...
ImageRead Article Now Book Mark ArticleStroke
A stroke occurs when blood flow to a part of the brain stops. A stroke is sometimes called a "brain attack. " If blood flow is cut off for longer th...
ImageRead Article Now Book Mark Article - Heart failure
Heart failure
Heart failure is a condition in which the heart is no longer able to pump oxygen-rich blood to the rest of the body efficiently. This causes symptom...
ImageRead Article Now Book Mark Article - Impaired thirst
- Limited access to water (especially in people with dementia or who are bedbound)
- Older age
- Poor kidney function
- Poor management of diabetes, not following the treatment plan as directed
- Stopping or running out of insulin or other medicines that lower glucose level
Symptoms
Symptoms may include any of the following:
- Increased thirst and urination (at the beginning of the syndrome)
Increased thirst
Excessive thirst is an abnormal feeling of always needing to drink fluids.
ImageRead Article Now Book Mark ArticleUrination
Excessive amount of urination means that your body makes larger than normal amounts of urine each day.
ImageRead Article Now Book Mark Article - Feeling weak
- Nausea
- Weight loss
- Dry mouth, dry tongue
- Fever
- Seizures
- Confusion
- Coma
Symptoms may get worse over days or weeks.
Other symptoms that may occur with this disease:
- Loss of feeling or function of muscles
- Problems with movement
- Speech impairment
Exams and Tests
Your health care provider will examine you and ask about your symptoms and medical history. The exam may show that you have:
- Extreme dehydration
- Fever higher than 100.4°F (38°C)
- Increased heart rate
- Low systolic blood pressure
Tests that may be done include:
- Blood osmolarity (concentration)
Blood osmolarity (concentration)
Osmolality blood test is a test that measures the concentration of all chemical particles found in the fluid part of blood. Osmolality in the urine c...
ImageRead Article Now Book Mark Article - BUN and creatinine levels
Creatinine
The creatinine blood test measures the level of creatinine in the blood. This test is done to see how well your kidneys are working. Creatinine in t...
ImageRead Article Now Book Mark Article - Blood sodium level (needs to be adjusted for the blood glucose level)
- Ketone test
Ketone test
A ketone blood test measures the amount of ketones in the blood. Ketones can also be measured with a urine test.
ImageRead Article Now Book Mark Article - Blood glucose, potassium, and bicarbonate
Blood glucose
A blood sugar test measures the amount of a sugar called glucose in a sample of your blood. Glucose is a major source of energy for most cells of the...
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Evaluation for possible causes may include:
- Blood and urine cultures
- Chest x-ray
- Electrocardiogram (ECG)
- Urinalysis
Urinalysis
Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds th...
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- CT scan of the head
Treatment
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. A high glucose level may be treated with insulin given through a vein.
Outlook (Prognosis)
People who develop HHS are often already ill. If not treated right away, seizures, coma, or death may result.
Possible Complications
Untreated, HHS may lead to any of the following:
- Shock
- Blood clot formation
- Brain swelling (cerebral edema)
- Increased blood acid level (lactic acidosis)
When to Contact a Medical Professional
This condition is a medical emergency. Go to the emergency room or call 911 or the local emergency number if you develop symptoms of HHS.
Prevention
Controlling type 2 diabetes and recognizing the early signs of dehydration and infection can help prevent HHS. Have a sick-day plan so you will be prepared for days when you are not going to be eating well. Also try to order your diabetes and other medicines in 3-month amounts so you will be less likely to run out of them.
Reviewed By
Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Dhatariya KK, Umpierrez GE, Crandall JP. Diabetes mellitus. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 210.
Lebovitz HE. Hyperglycemia secondary to non-traditional diabetic conditions. In: Robertson RP, ed. DeGroot's Endocrinology. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 35.
Sinha A. Diabetic emergencies. In: Bersten AD, Handy JM, eds. Oh's Intensive Care Manual. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 59.