Diabetic Ketoacidosis Presenting With New-Onset Generalized Tonic–Clonic Seizures and Status Epilepticus in a Previously Undiagnosed Diabetic Patient: A Case Report

We present the case of a 47-year-old Moroccan male with no known history of diabetes who presented with new-onset status epilepticus. His family reported a one-year history of increasing lethargy, polyuria, polydipsia, significant weight loss, and polyphagia. Initial laboratory investigations revealed severe hyperglycemia (547 mg/dL), marked ketosis, and profound metabolic acidosis (bicarbonate level of 9 mmol/L), confirming the diagnosis of severe diabetic ketoacidosis. Further investigations, including an elevated HbA1c level (15.2%), positive anti-glutamic acid decarboxylase (GAD) antibodies (280 IU/mL), and a low fasting C-peptide level (0.06 ng/mL), supported the diagnosis of new-onset latent autoimmune diabetes in adults. Neuroimaging and electroencephalography ruled out other neurological etiologies, supporting diabetic ketoacidosis-induced status epilepticus as the most likely cause. Status epilepticus as the initial manifestation of diabetic ketoacidosis secondary to latent autoimmune diabetes in adults is rare and clinically challenging. Treatment consisted of intravenous fluids, regular insulin, and phenobarbital for seizure control, leading to progressive clinical and biochemical improvement. This case highlights the importance of early metabolic evaluation in adults presenting with new-onset seizures, even in the absence of previously known diabetes, to allow timely diagnosis and prevent severe neurological complications.