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****Please do each question in order to fully appreciate this stem*****

A 45-year-old man is admitted to the hospital for the evaluation of diplopia, weakness of his lower extremities, and gait difficulties. During the
interview, the patient reveals that has been forcing himself to vomit after almost every meal over the last 6 weeks. He denies associated eye
pain and discomfort, headache, or dysphagia. He has never experienced such symptoms in the past. Examination of the patient demonstrates
slight disorientation, vertical nystagmus worse on downgaze, diffuse weakness of the lower extremities, bilateral dysmetria, and hypothermia.
Laboratory analyses reveal mild dehydration and hypokalemia.

Question 1 of 5

Which of the following is the most likely diagnosis?
/ A. Anticonvulsant intoxication
/ B. Benedict syndrome
/ C. Delirium tremens
/ D. Wernicke encephalopathy
/ E. Wernicke-Korsakoff syndrome

Question 2 of 5
The patient's status has improved after an administration of a vitamin. This vitamin plays a central role in the metabolism of which of the
following compounds?
/ A. Amino acids
/ B. Carbohydrates
/ C. Cholesterol
/ D. DNA
/ E. Fatty acids

Question 3 of 5

The physiologically active form of this vitamin acts as a coenzyme for which of the following enzymes?
/ A. GIycogen phosphorylase
/ B. L-methylmalonyI-CoA mutase
/ C. Methionine synthase
/ D. Pyruvate carboxylase
/ E. Pyruvate dehydrogenase

Question 4 of 5
Which of the following would be the most appropriate initial therapy for this patient?
/ A. Chlordiazepoxide
/ B. Cyanocobalamin
/ C. GIucose
/ D. Niacin
/ E. Thiamine

Question 5 of 5
Pathologic examination of this patient's brain would most likely reveal damage to which of the following structures?
/ A. Caudate nucleus and putamen
/ B. Midline brain structures
/ C. Motoneurons in the anterior horns and cranial motor nuclei
/ D. Posterior columns and posterior roots
/ E. Substantia nigra

D
b
e
C
b

any 1 else?

e
b
e
e
b

e b e e b

D. Wernicke encephalopathy
B. Carbohydrates
E. Pyruvate dehydrogenase
E. Thiamine
B. Midline brain structures

what is the diff btw....wernicke encephalopathy and the kosakoffcounterpart......
i think u are right ok3...which of the 2 has confussion as its mannifestation?

i made mistak first thiamine then glucose.

sorry had to tuck in the kids...

1.The correct answer is D. Wernicke encephalopathy is caused by a nutritional deficiency of thiamine. Classic symptoms and signs include "Wernicke's triad": acute mental confusion, ataxia, and ophthalmoplegia, although not all the patients present with all of these. A common misconception about Wernicke encephalopathy is that it is seen exclusively in alcoholics. Prolonged vomiting and malnutrition, eating disorders, hunger strikes, prolonged intravenous feeding, and malabsorption syndrome can also be a potential cause of thiamine deficiency. Mental confusion is characterized by impaired awareness, spatial disorientation, and inability to concentrate. Ocular abnormalities are the hallmarks of this disease. Horizontal or vertical nystagmus and paralysis of lateral rectus muscles are common. The wide-based ataxic gait results from cerebellar dysfunction, either alone or in combination with vestibular dysfunction.
If persistent memory and learning deficits are present in addition to Wernicke's triad, the complex disorder is termed Wernicke-Korsakoff syndrome (choice E).

2.The correct answer is B. Thiamine (vitamin B1) is converted intracellularly to its active form, thiamine pyrophosphate, which is an essential cofactor in intermediate carbohydrate metabolism.

3.The correct answer is E. Thiamine pyrophosphate (TPP), the physiologically active form of thiamine, is required for the activity of pyruvate dehydrogenase (PDH).

4.The correct answer is E. 50-100 mg of thiamine IV should be administered promptly. Objective of thiamine therapy is to replenish vitamin stores.
Glucose (choice C) infusion before thiamine administration may precipitate Wernicke disease. ( i made this mistake in class and my proffessor really ragged me)

5.The correct answer is B. Midline brain structures show significant damage in patients with Wernicke encephalopathy

thanks....inv8ed