A 54-year-old man is brought to the office by his daughter. She says that her father has been acting strangely over the past 2 years. He makes inappropriate sexual jokes, has little regard for social rules, is often irritable, and is borderline aggressive at times. The patient denies that his personality is any different from normal. When speaking with the patient, the physician notices that he has minimal verbal output and repeats "it is what it is" when asked questions about his strange behavior. On physical examination, he appears unkempt but otherwise has no significant findings. This patient most likely has a condition that predominantly involves which of the following structures?

Question

A 54-year-old man is brought to the office by his daughter.  She says that her father has been acting strangely over the past 2 years.  He makes inappropriate sexual jokes, has little regard for social rules, is often irritable, and is borderline aggressive at times.  The patient denies that his personality is any different from normal.  When speaking with the patient, the physician notices that he has minimal verbal output and repeats "it is what it is" when asked questions about his strange behavior.  On physical examination, he appears unkempt but otherwise has no significant findings.  This patient most likely has a condition that predominantly involves which of the following structures?

Quizplus · Accepted Answer

11ec160b_39be_cf09_9249_fdda2cdf2bab_MD0001_00 This patient's personality and behavioral changes (eg, disinhibition, apathy, social inappropriateness, compulsive behaviors) and altered speech patterns (eg, paucity of speech, repeated phrases) are consistent with a diagnosis of behavioral variant frontotemporal dementia (FTD). Personality and behavioral changes present early in the disease course with neurocognitive deficits occurring later. FTD is highly heritable and a common cause of early-onset dementia. FTD is characterized by initial degeneration of the prefrontal cortex that eventually progresses to include the anterior temporal cortex. Loss of function in the prefrontal cortex can cause inappropriate behavior, impaired judgment, and poor problem-solving skills (ie, executive dysfunction). (Choice B) The caudate nucleus and putamen are basal ganglia structures that together form the dorsal striatum, which regulates voluntary movements. Huntington disease causes atrophy of the dorsal striatum (there is greater relative atrophy of the caudate) and presents with choreiform movements, psychiatric symptoms (eg, irritability, depression), and dementia. This patient's prominent personality changes and lack of a movement disorder are not characteristic of Huntington disease. (Choice C) Neuronal loss in the locus ceruleus and substantia nigra is seen in Parkinson disease, which typically presents with tremor, bradykinesia, and rigidity. The locus ceruleus is a pontine structure that is one of the primary areas of norepinephrine synthesis in the brain. The substantia nigra, located in the midbrain, contains dopaminergic neurons whose axons project to the striatum (nigrostriatal pathway) and participate in regulation of voluntary movements. (Choice D) Damage to the mammillary bodies and medial thalamus is characteristic of chronic Wernicke encephalopathy and Korsakoff syndrome. Both disorders result from chronic thiamine deficiency, most often in the context of heavy alcohol use. (Choice E) Medial temporal and parietal cortical atrophy is characteristic of Alzheimer disease. The medial temporal lobe contains the hippocampus, a structure involved in the formation of new memories. (Choice F) Disproportionate atrophy of the parietal and occipital cortices is seen in posterior cortical atrophy, an atypical variant of Alzheimer disease with prominent visual symptoms. Educational objective: Frontotemporal dementia is associated with pronounced atrophy of the prefrontal cortex with later degeneration of the anterior temporal cortex. It manifests initially with changes in personality, social behavior, and language that progress over time to a more global dementia with obvious neurocognitive deficits. __________ References: Behavioural-variant frontotemporal dementia: diagnosis, clinical staging, and management. (http://www.ncbi.nlm.nih.gov/pubmed/21147039) Sensitivity of revised diagnostic criteria for the behavioural variant of frontotemporal dementia. (http://www.ncbi.nlm.nih.gov/pubmed/21810890)

A 54-Year-Old Man Is Brought to the Office by His