[Diabetic ketoacidosis masked by metabolic alkalosis]

Diabetic ketoacidosis is caused by accumulation of acetoacetic and β-hydroxybutyric acids and is a common acute metabolic complication of type 1 diabetes mellitus. A much less common and recognized metabolic complication is diabetic ketoacidosis with alkalaemia ("ketoalkalosis"). Diuretic use, vomiting, alkali ingestion, and hypercortisolism have all been implicated as potential causes of this disorder. We present a case in which a patient displayed significantly elevated blood β-hydroxy-butyrate (7.8 mmol/l) and glucose (39 mmol/l) concentrations together with arterial alkalosis (pH 7.47).