What is the diagnosis of Hyperosmolar Hyperglycemic State (HHS)?

From the Guidelines

Diagnosis of Hyperosmolar Hyperglycemic State (HHS) should be based on the presence of severe hyperglycemia, hyperosmolality, and dehydration without significant ketoacidosis, with diagnostic criteria including a plasma glucose level >600 mg/dL, serum osmolality >320 mOsm/kg, serum pH >7.3, bicarbonate >15 mEq/L, minimal ketonemia and ketonuria, and profound dehydration with altered mental status 1. The diagnostic criteria for HHS include:

• Plasma glucose level typically >600 mg/dL (33.3 mmol/L)
• Serum osmolality >320 mOsm/kg
• Serum pH >7.3
• Bicarbonate >15 mEq/L
• Minimal ketonemia and ketonuria
• Profound dehydration with altered mental status ranging from confusion to coma Laboratory evaluation should include:
• Comprehensive metabolic panel
• Complete blood count
• Urinalysis
• Serum ketones
• Arterial blood gases
• Calculation of effective serum osmolality using the formula: 2(Na+) + glucose/18 + BUN/2.8 1 Additional testing should include:
• Electrocardiogram
• Chest X-ray
• Blood cultures
• Urinalysis to identify precipitating factors such as infection HHS typically develops gradually over days to weeks, with patients often presenting with severe dehydration (average fluid deficit of 9-12 liters) and neurological symptoms 1. The absence of significant ketosis distinguishes HHS from diabetic ketoacidosis, though mixed states can occur 1. Early recognition is crucial as HHS carries a higher mortality rate (10-20%) than DKA, particularly in elderly patients with comorbidities 1.

From the Research

Diagnosis of Hyperosmolar Hyperglycemic State (HHS)

The diagnosis of HHS is based on the presence of several key features, including:

• Marked elevation of blood glucose, with a plasma glucose level >600 mg/dL 2
• Hyperosmolarity, with an effective plasma osmolality >320 mOsm/kg 3, 2
• Little or no ketosis, which distinguishes HHS from diabetic ketoacidosis (DKA) 4, 5, 3
• Profound dehydration and various neurologic symptoms, such as lethargy, coma, or seizures 4, 5, 6

Diagnostic Criteria

The diagnostic criteria for HHS include:

• Plasma glucose level >600 mg/dL 2
• Increased effective plasma osmolality >320 mOsm/kg 3, 2
• Absence of ketoacidosis 4, 5, 3
• Presence of dehydration and neurologic symptoms 4, 5, 6

Laboratory Tests

Laboratory tests that can aid in the diagnosis of HHS include:

• Blood glucose measurement 4, 5, 2
• Serum osmolality measurement 3, 2
• Electrolyte panel, including sodium and potassium levels 4, 5
• Urinalysis to check for ketones and glycosuria 4, 5

Physical Examination

Physical examination findings that can support the diagnosis of HHS include:

• Signs of dehydration, such as dry mouth, decreased urine output, and decreased skin turgor 4, 5, 6
• Neurologic symptoms, such as lethargy, coma, or seizures 4, 5, 6
• Presence of underlying illnesses, such as infection or stroke 3, 6