Review Question - QID 214589

A 23-year-old woman with a history of IV drug abuse, malingering, depression, and homelessness presents to the emergency department with an acute change in her behavior. The patient’s mother states that for the past 4 days she has been complaining of a severe headache. She has a history of severe headaches and has tried multiple migraine medications prescribed by a headache neurologist with poor control of her symptoms. She has been taking her prescribed medicine throughout the day, every day without improvement of her headache. The patient has been complaining of muscle pains and spasms followed by a burning sensation in her skin. She began vomiting this morning, and her mother noticed her acting bizarrely, talking to herself in her room and slamming doors. Her temperature is 97.6°F (36.4°C), blood pressure is 114/74 mmHg, pulse is 125/min, respirations are 22/min, and oxygen saturation is 100% on room air. Physical exam reveals a young, highly irate woman who is not willing to participate in a neurological exam but is moving all extremities without any notable deficits. She appears to be conversing with someone; however, the room is empty. Which of the following is the most likely etiology of this patient’s symptoms?