What are the diagnostic criteria for diabetic ketosis?

Diagnostic Criteria for Diabetic Ketosis

The diagnostic criteria for diabetic ketosis include blood glucose >200 mg/dL, venous pH <7.3 or serum bicarbonate <15 mEq/L, ketonemia >3 mmol/L, and presence of ketonuria. 1

Classification of Severity

The American Diabetes Association classifies the severity of diabetic ketoacidosis according to the following parameters:

Parameter	Mild	Moderate	Severe
Arterial pH	7.25-7.30	7.00-7.24	<7.00
Serum bicarbonate (mEq/L)	15-18	10-14	<10
Mental status	Alert	Alert/drowsy	Stupor/coma

2

Key Diagnostic Components

1. Hyperglycemia:

   • Blood glucose >200 mg/dL
   • Note: In rare cases, euglycemic diabetic ketoacidosis can occur with blood glucose <200 mg/dL, particularly with SGLT2 inhibitor use, pregnancy, decreased caloric intake, recent insulin use, alcohol consumption, or liver disease 3

2. Ketosis:

   • Direct measurement of β-hydroxybutyrate in blood (>3 mmol/L) is the preferred method for diagnosing and monitoring ketosis 2
   • Ketonuria is also present

3. Metabolic Acidosis:

   • Venous pH <7.3
   • Serum bicarbonate <18 mEq/L
   • Elevated anion gap

Clinical Presentation

Common symptoms and signs include:

• Polyuria with polydipsia (98%)
• Weight loss (81%)
• Fatigue (62%)
• Dyspnea (57%)
• Vomiting (46%)
• Abdominal pain (32%)
• Fruity odor on breath (due to ketones)
• Signs of dehydration
• Altered mental status (in severe cases)

4, 5

Laboratory Evaluation

To confirm the diagnosis of diabetic ketosis, the following tests should be performed:

• Blood glucose measurement
• Serum ketones (β-hydroxybutyrate preferred)
• Venous blood gas for pH and bicarbonate
• Electrolytes and anion gap calculation
• Urinalysis for ketones
• Complete blood count
• Blood urea nitrogen and creatinine

2, 4

Differential Diagnosis

Diabetic ketosis must be differentiated from:

• Hyperosmolar hyperglycemic state
• Starvation ketosis
• Alcoholic ketoacidosis
• Other causes of metabolic acidosis

4

Monitoring Resolution

Resolution of diabetic ketoacidosis is defined by the American Diabetes Association as:

• Glucose <200 mg/dL
• Serum bicarbonate ≥18 mEq/L
• Venous pH ≥7.3
• Normalization of the anion gap

2

Important Clinical Considerations

1. Early detection is crucial: About one-third of all cases occur in persons without a previous history of diabetes mellitus 4

2. Risk of complications: Without proper treatment, diabetic ketosis can progress to severe DKA with increased morbidity and mortality

3. Special populations: Children, pregnant women, and elderly patients may present differently and require specialized management approaches 2

4. Common precipitating factors: Infection, stroke, alcohol abuse, pancreatitis, myocardial infarction, trauma, and certain medications (corticosteroids, thiazides, sympathomimetic agents) 2

5. Emerging causes: SGLT2 inhibitors have been associated with euglycemic DKA, where ketoacidosis occurs despite relatively normal blood glucose levels 3

Direct measurement of blood ketones using point-of-care testing allows for rapid diagnosis and monitoring of ketosis resolution, which is particularly valuable in emergency settings 6.