What are the clinical signs and symptoms to diagnose diabetic ketoacidosis (DKA)?

Clinical Recognition of Diabetic Ketoacidosis

A patient presenting with diabetic ketoacidosis can be identified clinically by the combination of characteristic symptoms (polyuria, polydipsia, nausea/vomiting, abdominal pain), physical findings (Kussmaul respirations, dehydration signs, altered mental status), and rapid evolution of illness (typically <24 hours), which should prompt immediate laboratory confirmation of the diagnostic triad. 1

Classic Clinical Presentation

Cardinal Symptoms

• Polyuria, polydipsia, and polyphagia with weight loss are the most frequently reported symptoms in DKA 1, 2
• Gastrointestinal symptoms including nausea, vomiting, and abdominal pain are extremely common, with up to 25% experiencing coffee-ground emesis 1
• Weakness, malaise, and severe fatigue are frequently present 1, 2
• Dyspnea may be reported as the patient attempts to compensate for metabolic acidosis 2
• Preceding febrile illness is often part of the history, as infection is a common precipitating factor 2

Physical Examination Findings

• Kussmaul respirations (deep, labored breathing pattern) are the hallmark sign indicating metabolic acidosis 1
• Dehydration signs including poor skin turgor, dry mucous membranes 1
• Tachycardia and hypotension result from volume depletion 1
• Altered mental status ranging from full alertness to profound lethargy, stupor, or coma depending on severity 1, 3
• Fruity odor on breath from acetone 4
• Normothermia or hypothermia may be present even with underlying infection, with hypothermia being a poor prognostic sign 1

Temporal Evolution

• DKA typically evolves rapidly, usually within less than 24 hours, which distinguishes it from hyperosmolar hyperglycemic state that develops over days to weeks 1
• The first symptoms usually come on gradually over hours or days and include drowsy feeling, flushed face, thirst, and loss of appetite 4
• Heavy breathing and rapid pulse are more severe symptoms that develop as acidosis worsens 4

Critical Clinical Pitfall: Euglycemic DKA

Be aware that DKA can present with normal or near-normal glucose levels (<250 mg/dL), particularly in patients taking SGLT2 inhibitors, and this can lead to delayed diagnosis. 1, 3

High-Risk Scenarios for Euglycemic DKA

• SGLT2 inhibitor use is the most important modern risk factor 1, 3
• Pregnancy 1
• Reduced food intake or starvation 1
• Alcohol use 1
• Liver failure 1
• Recent insulin administration 5

Clinical Approach When Euglycemic DKA is Suspected

• Maintain high suspicion for DKA in any diabetic patient with metabolic acidosis and ketosis, regardless of glucose level 6
• The same clinical symptoms and physical findings apply, but the absence of marked hyperglycemia may mislead clinicians 5
• Even hypoglycemia can occur concurrently with DKA, particularly with SGLT2 inhibitors 6

Severity Assessment by Mental Status

• Mild DKA: Patient is alert 3
• Moderate DKA: Patient is alert or drowsy 3
• Severe DKA: Patient exhibits stupor or coma 3

Common Precipitating Factors to Identify

• Infection is the most common precipitating factor 1
• New-onset type 1 diabetes (DKA may be the initial presentation, especially in children) 1, 2
• Insulin omission or inadequate insulin dosing 1
• Cerebrovascular accident or myocardial infarction 1
• Drug use including corticosteroids, thiazides, sympathomimetic agents 1
• Alcohol abuse 1
• Pancreatitis 1

Immediate Laboratory Confirmation Required

While clinical recognition is crucial, diagnosis cannot be made on clinical grounds alone and requires immediate laboratory testing to confirm the diagnostic triad:

• Hyperglycemia (blood glucose >250 mg/dL, though may be lower in euglycemic DKA) 1, 3
• Metabolic acidosis (arterial pH <7.3 AND serum bicarbonate <18 mEq/L) 1, 3
• Elevated ketones (positive serum or urine ketones, preferably β-hydroxybutyrate >0.6 mmol/L) 1, 3
• Elevated anion gap (>10-12 mEq/L) 1, 3