An 18-year-old female patient presents with high-grade fever, tachypnea, and altered mentation to the emergency department. She had diarrhea for 3 days that was watery and large in volume. On examination, she was found to be febrile with a temperature of 101 °F. Her pulse rate was 130/min regular, and her blood pressure was 90/70 mmHg. She had a Glasgow coma score of 9. Her random plasma glucose on arrival was 480 mg/100 mL. She was not known to have diabetes.