Concurrent Thyroid Storm and Diabetic Ketoacidosis Associated With Evolving Autoimmune Diabetes in a Patient With Untreated Hyperthyroidism

Thyroid storm and diabetic ketoacidosis (DKA) are life-threatening endocrine emergencies that rarely occur concurrently.Their coexistence presents significant diagnostic and management challenges, particularly when associated with new-onset autoimmune diabetes.We report the case of a 26-year-old female with untreated hyperthyroidism who presented with altered mental status, severe tachycardia, dehydration, and generalized weakness.Laboratory evaluation demonstrated thyroid storm with undetectable thyroid-stimulating hormone (TSH) and markedly elevated thyroid hormone levels.Concurrent findings were consistent with severe DKA, including hyperglycemia (828 mg/dL), high anion gap metabolic acidosis, ketonemia, and ketonuria.Hemoglobin A1c was elevated to 9.5% from 5.4% less than three months earlier, suggesting rapid progression to insulin deficiency.Low Cpeptide levels of 0.4 further support evolving autoimmune diabetes.The patient additionally demonstrated severe hyperosmolar hypernatremia, acute kidney injury, supraventricular tachycardia, and elevated cardiac biomarkers likely secondary to metabolic stress.She was treated in the intensive care unit (ICU) with aggressive intravenous fluid resuscitation, insulin infusion, electrolyte correction, beta blockade, corticosteroids, and antithyroid therapy, resulting in rapid clinical and biochemical improvement.This case highlights the rare presentation of concurrent thyroid storm and DKA associated with evolving autoimmune diabetes in a patient without previously established diabetes mellitus.Early recognition and prompt multidisciplinary management are essential to reduce morbidity and mortality.