Can euglycemic diabetic ketoacidosis (DKA) occur with a normal Hemoglobin A1c (HbA1c) level?

Euglycemic DKA Can Occur with a Normal HbA1c of 5.5%

Yes, euglycemic diabetic ketoacidosis (DKA) can occur in patients with a normal hemoglobin A1c of 5.5%, as the pathophysiology depends on acute metabolic derangements rather than long-term glycemic control.

Understanding Euglycemic DKA

Euglycemic DKA is characterized by:

• Metabolic acidosis (arterial pH <7.3)
• Ketosis/ketonemia
• Blood glucose <200 mg/dL (11.1 mmol/L) 1

This condition presents a significant diagnostic challenge as the normal blood glucose levels can mask the underlying ketoacidosis, potentially leading to delayed diagnosis and treatment.

Pathophysiology and Risk Factors

Euglycemic DKA occurs due to:

1. Insulin deficiency - Relative or absolute insulin deficiency is the primary driver, regardless of long-term glycemic control
2. Continued ketogenesis - Despite normal glucose levels

Common precipitating factors include:

• Recent use of insulin with inadequate carbohydrate intake 2
• Decreased caloric intake or starvation 3
• Ketogenic (low-carbohydrate) diets 4
• Heavy alcohol consumption 2
• Chronic liver disease 2
• Pregnancy 1
• SGLT2 inhibitor use 1, 5
• Acute illness, infections, surgery, or trauma 6

HbA1c and Euglycemic DKA

HbA1c reflects average blood glucose levels over the previous 2-3 months, but euglycemic DKA is an acute condition that can develop rapidly due to specific triggers, regardless of prior glycemic control. A normal HbA1c of 5.5% does not protect against euglycemic DKA if precipitating factors are present.

Key points about HbA1c in this context:

• HbA1c remains the best clinical marker of long-term glycemic control 1
• A normal HbA1c indicates good average glucose control but doesn't preclude acute metabolic derangements
• Euglycemic DKA has been reported in patients with newly diagnosed diabetes who may have relatively normal HbA1c levels 4

Clinical Presentation and Diagnosis

Patients with euglycemic DKA typically present with:

• Nausea, vomiting, malaise, fatigue
• Tachycardia, tachypnea
• Abdominal pain
• Dehydration

Diagnostic criteria (all must be present):

• Anion gap metabolic acidosis (pH <7.3, bicarbonate <18 mEq/L)
• Ketonemia or ketonuria
• Blood glucose <200 mg/dL 1, 2

Management Considerations

Despite euglycemia, treatment follows similar principles to standard DKA management:

• Intravenous fluids (initially 0.9% NaCl) 7
• Insulin therapy (may require dextrose-containing fluids to prevent hypoglycemia) 7
• Electrolyte replacement (particularly potassium)
• Treatment of underlying precipitating factors
• Close monitoring of glucose, electrolytes, pH, and anion gap 7

Clinical Pitfalls to Avoid

1. Overlooking the diagnosis due to normal glucose levels
2. Failing to check ketones in ill diabetic patients with normal glucose levels
3. Delaying appropriate treatment due to absence of hyperglycemia
4. Not identifying the underlying trigger for euglycemic DKA
5. Inadequate monitoring during treatment

Conclusion

Euglycemic DKA is a medical emergency that can occur in patients with a normal HbA1c of 5.5%. The diagnosis requires high clinical suspicion, especially in patients with risk factors such as reduced carbohydrate intake, SGLT2 inhibitor use, or acute illness. Blood or urine ketones should be checked in ill patients with diabetes regardless of blood glucose levels 3.