Neurophysiology

Case 1:

A 10-year-old boy is brought to the family physician because the child is having problems at school. In a parent-teacher conference, the teacher complained that this child is inattentive, rude to others, and a poor student. The teacher indicates that the child does not listen, does not always respond to others or acknowledge them, and doesn't care about remembering anything. The child complains that other children treat him badly, making him the brunt of jokes, talking about him, and picking on him in physical education classes. For example, when playing volleyball, the ball is always spiked or served in his direction, often striking him before he can move. His father recounts many episodes during the past 6 months in which he remarked to the boy, "What did I just tell you?" Before this year in a new school, the child was doing well with no problems.

A physical examination reveals no abnormalities. The neurologic examination is normal.

Questions:

1.1 What is the likely diagnosis?

1.2 What should be done next?

1.3 What pharmacologic therapy may be indicated for treatment?

1.4 Explain the mechanism of action of the drug therapy.

1.5 What is the prognosis?

Case 2:

A 65-year-old man has recently retired from working at a savings & loan institution. He is looking forward to having more time to do the things he has always wanted to do, such as building his own sailboat, and spending more time traveling with his 68-year-old wife. He returns home one evening after spending a day at the local home center. He sits down to eat dinner. Bleaahhh. Something is wrong. The food tastes terrible. "What did you do, honey?" he asks his wife. She replies, "It is your favorite." She doesn't appear to notice. He goes into the kitchen and looks around. He quickly determines that, instead of cooking oil, dishwashing liquid has been used on the food. This incident becomes a focal point for the realization that things have not been going that well at home...for some time. He now remembers that his wife used to pay all the bills, but she began to miss payments, and he started performing this function 3 years ago. She has become more housebound and sleeps more in the past year. Friends have remarked that she seems less sociable. He recalls several episodes in the past year in which she remarked, "Did you see that?" and he didn't see what she claimed was there. She has had minor falls, without injuries other than superficial contusions of arms and legs.

Questions:

2.1 What problems should you consider?

2.2 What can you do next?

2.3 What do these findings suggest?

2.4 What pharmacologic therapy may be useful?

2.5 Explain the neurophysiology of the drug therapy.

Case 3:

A 22-year-old man has been noted by his friends to become withdrawn over the past 6 months. He socializes with them less and less. When playing cards with them, he annoys them by failing to keep track of what is going on. He has used up all his vacation days at work due to absences. When he fails to show up for work for 3 days in a row, and does not answer when telephone calls are made to his apartment, the office manager calls local law enforcement to check on him. A police officer finds the door locked. Upon obtaining a key from the apartment complex manager, he enters the apartment to find the man sitting in a corner, in a disheveled state, with the strong smell of urine. He does not respond when the officer addresses him. The officer calls for an ambulance. When the paramedics begin to move him, he becomes agitated and says, "No...no...there is a soldier standing by the door telling me not to move."

Questions:

3.1 What should be considered?

Additional history:

On physical examination, he has a temperature of 36.8 C, pulse 85/min, respiratory rate 17/min, and blood pressure 100/65 mm Hg. There are no signs of trauma. His lungs are clear to auscultation and his heart rate is regular with no murmurs. The abdominal examination is unremarkable. The neurologic examination shows cranial nerves II-XII intact. Motor and sensory function is intact, with 5/5 motor strength in all extremities, but with motor rigidity noted. A tremor of his outstretched hands is noted.

He is admitted to the hospital psychiatric ward for 3 days, under statute, for evaluation and observation.

3.2 What pharmacologic therapy may be indicated for treatment?

3.3 Explain the mechanism of action of the drug therapy.

Case 4:

A 44-year-old man is brought to the emergency department by a co-worker after he is noted to have a seizure. It was noted that he let out a moan, followed by intense muscular contractions involving arms and legs, followed in less than a minute by alternating muscular relaxation and contraction. He was turning blue. Finally, after a couple of minutes, the periods of muscuclar relaxation predominated until he became flaccid but still unresponsive. His breathing became regular and his colour returned. He was drooling, and his pants were wet with urine (which explained why only one of his friends volunteered to take him to the ED).

In the emergency department, he becomes responsive but does not remember the episode. After waiting 2 hours to see a physician, he has a headache and myalgias. On physical examination there are no abnormal findings. The neurologic examination is normal. Laboratory studies show Hct 44%, blood glucose 77 mg/dL, and serum creatinine 1.1 mg/dL.

Questions:

4.1 What is the most likely diagnosis?

4.2 What should be done next?

4.3 What pharmacologic therapy may be indicated for treatment?

4.4 Explain the mechanism of action of the drug therapy.

4.5 Why must phenytoin be monitored carefully?

4.6 What is required of the physician to report regarding this incident?

Case 5:

A 72-year-old woman is brought to a physician by her husband, who is concerned about her declining health. She no longer prepares meals or cleans the house. She takes no interest in her bridge club and has not gone out with any friends for over 2 months. She sleeps about 14 to 16 hours a day. Her husband states that when she does wake up in the morning, he wishes she would just go back to bed, because she is always in a very foul mood. She says she feels fatigued. She has trouble remembering things.

On physical examination her vital signs show temperature 37.1 C, pulse 70/min, respiratory rate 14/min, and blood pressure 138/88 mm Hg. There are no abnormal findings. The mental status examination shows that she can remember 2 of 3 objects after 3 minutes. She can do serial sevens, but it takes a while. She is oriented. The physician becomes impatient as the examination drags on, and the patient is not cooperative, often replying, "I don't care" or "It doesn't matter."

Questions:

5.1 What is the most likely diagnosis?

5.2 What pharmacologic therapy may be indicated for treatment?

5.3 Explain the mechanism of action of the drug therapy.

Case 6:

A 30-year-old woman has experienced odd movements of her right hand for the past year. These episodes have occurred at various times during the day, about 3 or 4 times a month. An episode begins with what she describes as "twitching" of her fingers for about a minute, followed by "shaking" of her whole hand "as if I were beating a drum." Sometimes during one of these episodes she experiences an intense odor of burning toast (but she doesn't own a toaster). She does not lose consciousness. Episodes have never lasted more than 5 minutes. A friend once asked her why she was making faces during an episode.

Physical examination by her physician shows normal vital signs. There are no abnormal findings. The neurologic examination is normal.

Questions:

6.1 What are diagnostic possibilities?

6.2 What should be done next?

6.3 What pharmacologic therapy may be indicated for treatment?

6.4 Explain the mechanism of action of the drug therapy.

Case 7:

A 31-year-old man has the sudden onset of right periorbital pain. The pain worsens over the next 5 minutes and then remains at an excruciating, deep, non-flucuating level for the next 45 minutes. He has a friend drive him to the emergency department. While waiting in line to be seen over the next hour, the pain gradually subsides. When seen by the physician's assistant, he is afebrile and normotensive with pulse 80/min and respiratory rate 15/min. The pain is unilateral. He has homolateral lacrimation, reddening of the right eye, nasal stuffiness, and right lid ptosis. He is nauseated.

Over the next 2 months, he has several more similar episodes, each involving the right side. However, the next episode does not occur until a year later.

Questions:

7.1 What is the most likely diagnosis?

7.2 Is pharmacologic therapy indicated?

7.3 What if he had a recurring headache building up over 4 to 72 hours, maintained for several hours to days, and relieved by sleep, characterized by a pulsating quality and unilateral location, nausea, vomiting, and/or other symptoms including photophobia, light-headedness, visual disturbances, paresthesias, and vertigo? What therapy would be indicated?

Case 8:

A 35-year-old military officer leads an expedition to the west coast for 18 months. During this journey he has episodes lasting 1 to 6 weeks in which he exhibits a decreased need for sleep, feeling rested after only 3 hours of sleep. He becomes very goal-directed, which aids in his documentation of findings, but in his journals he jumps from one idea to another quickly. Between these episodes he becomes morose and far less talkative. Upon his return from the expedition, he takes an administrative job in St Louis, but becomes unable to keep up with the demands of his work. He acquires debts he cannot repay. While on a business trip to Washington, D.C., to try and secure a loan, he stops at Grinder's Stand, in Tennessee. Later that evening, shots are heard. He is found deceased, with contact range gunshot wounds to the chest and forehead.

The following synopsis was written by his "Chief Executive" and friend: "Governor L. had, from early life, been subject to hypochondriac affections. It was a constitutional disposition in all the nearer branches of the family of his name, and was more immediately inherited by him from his father. They had not, however, been so strong as to give uneasiness to his family. While he lived with me in Washington I observed at times sensible depressions of mind: but knowing their constitutional source, I estimated their course by what I had seen in the family. During his western expedition, the constant exertion which that required of all the faculties of body and mind; suspended these distressing affections; but after his establishment at St. Louis in sedentary occupations, they returned upon him with redoubled vigour, and began seriously to alarm his friends. He was in a paroxysm of one of these, when his affairs rendered it necessary for him to go to Washington."

Questions:

8.1 What is the most likely diagnosis? Who is this? Who is the Chief Executive? What is the manner of death?

8.2 What pharmacotherapy currently available would have been helpful in treating this man?

8.3 Explain the neurophysiology of this disorder and how the drugs work.

Case 9:

A 24-year-old woman has a slowly building headache with a bilateral, tight "bandlike" distribution. The pain fluctuates in intensity for the next 4 hours before subsiding. She experiences similar headaches on average once per month for the next 40 years.

Questions:

9.1 What is the most likely diagnosis?

9.2 What therapy is indicated?