Delirium: A Neurologist's View by Lou Caplan

Case 1

You are asked by the patient's wife to see Mr. A, a 60 year old, right-handed man who has recently been asked by his employer to take early retirement. Apparently he has been making mistakes on the job in recent months and his boss is concerned. For examples, he "forgot" to make a business insurance premium payment, and he was unable to complete an important report about recent new business projects. His employer believes that the patient is no longer "interested" in his job. Mrs. A has also noted subtle changes. She finds him irritable and defensive in the past 3-6 months. He sometimes seems preoccupied and has lost his way while driving on several occasions. He has explained this as a matter of having "too much on my mind." He has begun to repeat himself in conversations.

Mr. A is guarded and suspicious. His general examination is unremarkable. He is oriented to month, day of the week, and year but not to the date. He spells the word WORLD in reverse as DLORD. He remembers none of three items after an interval of two minutes. He recalled his military history and employment record in detail. He calculates slowly and makes one error with serial 7's. When corrected he responds that the task was "too simple for him to bother with." When asked how a "stitch in time saves nine," he responds that "tailors should not be in too great a hurry." He has difficulty with a three part command and refuses to try again. His cube drawing does not capture perspective. The rest of the neurological examination is normal.


Case 2

A 38 year old man is brought to the emergency room for "talking crazy and staggering around" by a friend. The friend emphatically denies that either of them has been drinking heavily. He describes the patient as having been clear-headed  just three days earlier. The patient's chart reveals admissions for pancreatitis, seizures and head trauma. He has chronic liver disease with coagulopathy, and hypertension. He is supposed to be taking phenytoin and nadolol.

On exam, the patient is awake but does not appear 100% alert. He is disheveled and very thin. He does not smell of alcohol. His temperature is 96.0 F. His BP is 179/100; HR is 112. He thinks he is at the Salvation Army. He knows the year but not the date, month, or season. He speaks fluently about living in a hotel (his friend denies this) and says he has a letter there that can explain everything. He cannot name the Cardinals' lineup, a finding that leaves his friend flabbergasted. He can follow only one step commands. He can recall only one of the three objects at two minutes, and doesn't remember the name of the hospital (despite your telling him earlier). He cannot even begin serial sevens. He cannot spell a three-letter word backwards. He has nystagmus when he looks to either side. Face and limb movements are symmetrical, but he has an irregular tremor when he holds out his arms. Tendon reflexes are absent. His gait is wide-based and ataxic.



  1. Is there additional history that might be helpful to guide the work-up of these cases?

  2. Are there additional physical exam features that might be helpful?

  3. Both of these patients appear to have global cognitive dysfunction. What are the key points that differentiate them and why may differentiation be important?

  4. If there are no additional pertinent historical or PE details, present the five most likely diagnoses for each case. Even if not on your first list, indicate the five most important diagnoses that should be considered for each case.

  5. Describe your work-up for each case.

  6. In cases of confusion, what leads you to do an early brain imaging test? An LP? An EEG?

  7. For case 1, how would you alter the differential diagnosis for a young person (e.g. a 25 year old) with a similar picture of deterioration at work, personality change, and these examination findings?

  8. Among the many causes of mental status changes, name a few that you would most suspect in a 90 year old nursing home patient with acute confusion or somnolence.

Tom Ala, MD
May 7, 2002