Diabetic Ketoacidosis: Causes, Symptoms, and Diagnosis Explained

Diabetic ketoacidosis (DKA) is a serious and potentially life-threatening complication most commonly associated with type 1 diabetes. However, it can also occur in individuals with type 2 diabetes, particularly during periods of severe illness, infection, physiological stress, or improper adjustment or discontinuation of insulin therapy. Understanding the triggers and early warning signs is crucial for timely medical intervention and effective management.

Recognizing the Clinical Signs of DKA

One of the hallmark symptoms of DKA is a distinctive fruity or acetone-like odor on the breath—often described as smelling like rotten apples. This occurs due to the accumulation of ketones in the bloodstream, which are expelled through respiration. Alongside this telltale sign, patients frequently experience gastrointestinal disturbances such as loss of appetite, nausea, vomiting, and abdominal pain, which can sometimes be mistaken for acute abdomen conditions.

In addition to digestive issues, systemic symptoms become progressively more severe. These include fatigue, lethargy, and overall mental fogginess. Dehydration manifests physically through dry, inelastic skin and sunken eyes—classic indicators of fluid loss. Cardiovascular changes such as an elevated heart rate (tachycardia) and dropping blood pressure may signal worsening hypovolemia and require urgent attention.

Key Diagnostic Criteria for Confirmation

To confirm a diagnosis of diabetic ketoacidosis, healthcare providers rely on a combination of clinical evaluation and laboratory testing. Elevated blood glucose levels, typically above 250 mg/dL, are usually present but not always extreme. More definitive evidence comes from detecting ketones in the urine (ketonuria) using a simple dipstick test.

Blood Gas Analysis: Confirming Metabolic Acidosis

An arterial blood gas (ABG) test plays a pivotal role in diagnosis by revealing metabolic acidosis—characterized by a low blood pH (usually below 7.3) and decreased serum bicarbonate levels (often less than 18 mEq/L). This triad—hyperglycemia, ketonuria, and acidosis—forms the cornerstone of DKA diagnosis.

Increased urination (polyuria) due to osmotic diuresis is another common feature, further contributing to dehydration and electrolyte imbalances. Early recognition of these combined symptoms allows for prompt initiation of intravenous fluids, insulin therapy, and electrolyte replacement, significantly improving patient outcomes.

In summary, while DKA primarily affects those with type 1 diabetes, it should not be overlooked in type 2 patients under stressful physiological conditions. Awareness of its diverse presentation—from breath odor to neurological and cardiovascular changes—enables faster diagnosis and treatment, ultimately reducing complications and hospitalization rates.