A 55-year-old woman is brought to the emergency department after being found unconscious in her apartment by her roommate. First responders found empty bottles of acetaminophen and clonazepam as well as a note on the floor beside the patient. The patient had been increasingly isolative in recent months and hired a lawyer to help write a will last week. She has a long history of episodic sadness and despair dating back to her adolescence. During these periods of sadness, the patient often needs to be reminded to eat, get out of bed, and take care of herself; on 3 occasions, she was hospitalized after attempting to hang herself. Temperature is 37.2 C (99 F), blood pressure is 108/76 mm Hg, pulse is 88/min, and respirations are 12/min. She is somnolent but arousable. The remainder of the examination is within normal limits. Which of the following abnormalities is most likely to be present in this patient?

Question

A 55-year-old woman is brought to the emergency department after being found unconscious in her apartment by her roommate.  First responders found empty bottles of acetaminophen and clonazepam as well as a note on the floor beside the patient.  The patient had been increasingly isolative in recent months and hired a lawyer to help write a will last week.  She has a long history of episodic sadness and despair dating back to her adolescence.  During these periods of sadness, the patient often needs to be reminded to eat, get out of bed, and take care of herself; on 3 occasions, she was hospitalized after attempting to hang herself.  Temperature is 37.2 C (99 F), blood pressure is 108/76 mm Hg, pulse is 88/min, and respirations are 12/min.  She is somnolent but arousable.  The remainder of the examination is within normal limits.  Which of the following abnormalities is most likely to be present in this patient?

Quizplus · Accepted Answer

Low levels of 5-hydroxyindoleacetic acid (5-HIAA) in the cerebrospinal fluid (CSF) are associated with suicidal behavior. 5-HIAA is the primary metabolite of serotonin, which is one of the most important neurotransmitters responsible for modulating mood and behavior. Low levels of CSF 5-HIAA are thought to represent dysfunction of the serotonin system. Serotonin is the target of selective serotonin reuptake inhibitors, the class of medication considered first-line for depressive disorders. This patient has several important risk factors for suicide, including a history of suicide attempts (the strongest predictor of future suicidal behavior) and a history of psychiatric illness. Other risk factors for suicide include the presence of a medical illness, concerning substance use, and family history of suicide. (Choice A) A diffuse 3-Hz spike and wave pattern on electroencephalogram (EEG) is characteristic of childhood absence seizures, characterized by short period of profound impairment of consciousness with intact body tone. (Choices B and D) Generalized slowing with periodic sharp wave complexes on EEG and increased CSF 14-3-3 protein are seen in Creutzfeldt-Jakob disease (eg, progressive dementia, myoclonus, pyramidal/extrapyramidal dysfunction, mutism). (Choice C) Hydrocephalus ex vacuo on CT scan may be seen in some neurodegenerative conditions (eg, Alzheimer disease) and other diseases that lead to general cortical atrophy, which makes it appear as if the ventricles are enlarged. (Choice F) Low concentration of hypocretin (orexin) in the CSF is found in narcolepsy, characterized by daytime sleepiness, hallucinations, sleep paralysis, and cataplexy (transient muscle weakness with certain emotional states). Educational objective: 5-hydroxyindoleacetic acid (5-HIAA) is a metabolite of serotonin. Low cerebrospinal fluid 5-HIAA is associated with suicidal behavior. References: Positron emission tomography quantification of serotonin(1A) receptor binding in suicide attempters with major depressive disorder. (http://www.ncbi.nlm.nih.gov/pubmed/25549105)

A 55-Year-Old Woman Is Brought to the Emergency Department After