What are the symptoms of Hyperosmolar Hyperglycemic State (HHS)?

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From the Guidelines

Hyperosmolar Hyperglycemic State (HHS) is characterized by extreme hyperglycemia, profound dehydration, and altered mental status, with symptoms including excessive thirst, frequent urination, weakness, leg cramps, vision changes, and confusion progressing to lethargy and potentially coma. The symptoms of HHS can be divided into several categories, including:

  • General symptoms: excessive thirst, frequent urination, weakness, leg cramps, vision changes, and confusion progressing to lethargy and potentially coma 1
  • Neurological symptoms: seizures, hemiparesis, or visual hallucinations may occur due to severe hyperosmolarity 1
  • Physical findings: poor skin turgor, tachycardia, hypotension, alteration in mental status, shock, and ultimately coma (more frequent in HHS) 1 It is essential to note that HHS typically develops gradually over days to weeks, allowing severe dehydration to progress before diagnosis, and is most common in elderly patients with type 2 diabetes, particularly during illness or infection 1. Prompt recognition and treatment of HHS are critical, as the condition carries a mortality rate of 10-20%, and treatment requires aggressive fluid resuscitation, insulin therapy, and electrolyte management in a hospital setting.

From the Research

Symptoms of Hyperosmolar Hyperglycemic State (HHS)

The symptoms of HHS can be severe and life-threatening. Some of the key symptoms include:

  • Marked hypovolaemia (severe dehydration) 2, 3, 4
  • Hyperosmolarity (high levels of glucose, sodium, and urea in the blood) 2, 5, 6, 4
  • Hyperglycemia (high blood sugar levels) 2, 5, 6, 3, 4
  • Altered mental status, such as drowsiness or coma 5, 6, 3
  • Polydipsia (excessive thirst) and polyuria (excessive urination) 5
  • Neurological symptoms, such as seizures or cerebral oedema 2, 6
  • Abnormal electroencephalogram findings, such as nonconvulsive seizure activity 6

Clinical Features

The clinical features of HHS include:

  • Osmolality ≥320 mOsm/kg 4
  • Marked hyperglycaemia ≥30 mmol/L 4
  • Without significant ketonaemia (≤3.0 mmol/L) 4
  • Without significant acidosis (pH >7.3) and bicarbonate ≥15 mmol/L 4

Precipitating Causes

The precipitating causes of HHS can include:

  • Underlying infections 3
  • Certain medications 3
  • Non-compliance with diabetes treatment 3
  • Undiagnosed diabetes 3
  • Substance abuse 3
  • Coexisting disease 3

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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