Ketone breath

Specialty: Endocrine and metabolic.

• breath with the smell of apples
• ketotic fruit breath
• halitosis due to ketone bodies

Why it occurs

• Diabetic ketoacidosis (systemic accumulation of acetoacetate, beta-hydroxybutyrate and acetone, the latter being a volatile substance eliminated through the alveolar-capillary membrane)
• Alcoholic ketoacidosis (in patients with chronic alcoholism, severe malnutrition and decreased glycogen reserves that divert metabolism towards beta-oxidation of fatty acids)
• Starvation or prolonged voluntary or involuntary fasting (anorexia nervosa or extreme ketogenic diets without carbohydrates)
• Glycogenosis or congenital defects in the oxidation of fatty acids (innate metabolic disorders of cellular metabolism)

Initial workup

Determination of beta-hydroxybutyrate in capillary or plasma blood (more sensitive method than urinary detection of acetoacetate); arterial or venous gasometry with measurement of pH, pCO2 and bicarbonate; capillary and plasma glycemia; serum electrolytes to assess total electrolyte balance; urea nitrogen (BUN) and serum creatinine to rule out renal involvement; and plasma amylase/lipase.

Standard management

• 0.9% saline solution — priority intravenous infusion to rehydrate the vascular bed, dilute ketone bodies and restore the glomerular filtration rate for renal elimination
• Regular insulin — continuous intravenous infusion of 0.1 IU/kg/hour to stop tissue lipolysis and turn off the ketone body production pathway
• 5% or 10% glucose serum — added to the hydration scheme when plasma glucose decreases below 250 mg/dL, to allow continuous infusion of insulin until serum bicarbonate normalizes without inducing hypoglycemia
• Potassium chloride — supplementation according to plasma levels to prevent hypokalemia due to intracellular redistribution