Delirium Secondary to Diabetic Ketoacidosis Initially Misdiagnosed as Benzodiazepine Withdrawal: A Case Report

Background: Delirium is an acute neuropsychiatric syndrome characterized by disturbances in attention, awareness, and cognition with a fluctuating course, most often secondary to an underlying medical condition. Diabetic ketoacidosis (DKA) is a metabolic emergency that may present with prominent neuropsychiatric manifestations, sometimes mimicking primary psychiatric disorders or substance withdrawal syndromes, leading to diagnostic error. Case Presentation: We report the case of a 58-year-old woman with a 12-year history of type 2 diabetes mellitus who presented with acute psychomotor agitation, insomnia, and incoherent speech evolving over three days. The clinical context included abrupt discontinuation of lorazepam (2 mg/day for approximately 18 months), last taken approximately 72 hours prior to admission, without prior documented withdrawal episode or known dependence features. Initial evaluation led to suspicion of benzodiazepine withdrawal delirium. However, physical examination revealed dehydration, tachypnea, and systemic stress signs. Laboratory investigations showed hyperglycemia (2.55 g/L), ketonuria (3+), glycosuria, HbA1c of 12.1%, leukocytosis, and elevated C-reactive protein. Serum electrolytes and renal function were not fully available at presentation. Arterial blood gas analysis, serum bicarbonate, anion gap calculation, and serum β-hydroxybutyrate were also unavailable. Despite these limitations, a working diagnosis of DKA was retained based on clinical and urinary criteria. Treatment with intravenous fluids and insulin led to rapid improvement within 48 hours and full cognitive recovery by day four. Conclusion: This case highlights a diagnostic pitfall where metabolic delirium mimics benzodiazepine withdrawal. It underscores the necessity of systematic somatic evaluation in all acute confusional states, particularly in resource-limited settings, to avoid delayed diagnosis and prevent complications.