Question 31#

Which of the following is the most common intracranial opportunistic infection in HIV?

A. Toxoplasmosis

A. Toxoplasmosis is the most common opportunistic infection seen in AIDS patients. They may present with focal or diffuse cognitive or affective symptoms. Imaging may help with the diagnosis but may be normal in many cases. Definitive diagnosis is by biopsy. Cryptococcosis presents as meningitis with headache and fever. Other viral infections of the brain may present with personality and behavioural changes. HSV encephalitis typically presents with temporal lobe symptoms. CMV infection presents as encephalitis, retinitis, and peripheral neuropathies with demyelination. Progressive multifocal leucoencephalopathy is caused by a papova virus. The prognosis is poor.

Reference:

1. Hales RE and Yudofsky SC. The American Psychiatric Publishing Textbook of Neuropsychiatry and Clinical Neurosciences, 4th edn. American Psychiatric Press, 2002, p. 787.

Question 32#

All of the following features of hyperactive delirium help differentiate it from hypoactive delirium, except:

A. Restlessness

C. Hyperactive delirium is characterized by increased activity levels, including restlessness, loss of control of activities, and increased speed of action. Hypoactive delirium on the other hand is characterized by decreased activity levels including apathy, listlessness, and decreased speed of action. Hyperactive delirium may present with pressure of speech, altered content, and aggression, whereas hypoactive delirium usually presents with a decreased amount of speech and hypersomnolence. Hyperactive delirium is said to have a better prognosis than hypoactive delirium. But both types of delirium are characterized by diffuse slowing on the EEG.

Reference:

1. Hales RE and Yudofsky SC. The American Psychiatric Publishing Textbook of Neuropsychiatry and Clinical Neurosciences, 4th edn. American Psychiatric Press 2002, p. 543.

Question 33#

All of the following factors render a person at high risk for development of post-operative delirium except:

A. Baseline cognitive deficit

E. Along with a number of other factors, including extremes of age, pre-existing cognitive impairment, central nervous system disorders, medical comorbidity, medications, hypothermia, and electrolyte imbalance, hypoalbuminaemia is an important often unnoticed risk factor. Hypoalbuminaemia results in greater bioavailability of many drugs that use albumin as a transporter protein. This leads to greater side-effects resulting in delirium. This may not be picked up by carrying out therapeutic drug monitoring. In addition to the above, a number of surgical factors predispose to delirium, including long duration of operation, emergency procedures, and type of surgery (e.g. hip surgery).

Reference:

1. Hales RE and Yudofsky SC. The American Psychiatric Publishing Textbook of Neuropsychiatry and Clinical Neurosciences, 4th edn. American Psychiatric Press, 2002, p. 534.

Question 34#

Which of the following medication used in elderly people has the least propensity to induce delirium?

A. Digoxin

E. Atenolol is a water-soluble selective beta-blocker which has almost nil anticholinergic action. Further, due to its water-soluble property, atenolol does not cross the blood–brain barrier. All the other medications have some anticholinergic properties and may contribute to the presence of delirium, especially in older patients, who are more vulnerable and are often using multiple medications. Of these, cimetidine and prednisolone are particularly important.

Reference:

1. Hales RE and Yudofsky SC. The American Psychiatric Publishing Textbook of Neuropsychiatry and Clinical Neurosciences, 4th edn. American Psychiatric Press, 2002, p. 535.

Question 35#

All of the following are causes of diffuse slowing on EEG except:

A. Alcohol withdrawal delirium

A. Alcohol withdrawal delirium and benzodiazepine intoxication delirium present with low-voltage fast-activity on EEG. All the other options present with diffuse slowing, which is the pattern seen in most other cases. Frontocentral spikes are usually seen in toxic delirium, i.e. usually due to hypnosedative withdrawal or TCA and phenothiazine intoxication. Epileptiform activity may suggest post-ictal states or non-convulsive status epilepticus.

Reference:

1. Hales RE and Yudofsky SC. The American Psychiatric Publishing Textbook of Neuropsychiatry and Clinical Neurosciences, 4th edn. American Psychiatric Press, 2002, p. 539.