Nutritional and Metabolic Disorders Flashcards
(32 cards)
1
Q
1. In Tay-Sachs disease, the enzymatic abnormality responsible for the neurologic deficits is deficiency of a. Hexosaminidase A b. Glucocerebrosidase c. Phosphofructokinase d. Glucose phosphorylase e. Sphingomyelinase
A
a. Hexosaminidase A
a. Hexosaminidase A
a. Hexosaminidase A
2
Q
2. With β-glucosidase deficiency, the affected child is likely to exhibit abnormal accumulations of which of the following? a. Glucosylceramide b. G ganglioside c. Galactosyl sulfatides d. Sphingomyelin e. Trihexosylceramide
A
a. Glucosylceramide
3
Q
- A 53-year-old left-handed man presents with asterixis, esophageal
varices, splenomegaly, and abdominal ascites. He is likely to exhibit altered
consciousness on the basis of which of the following?
a. Renal tubular acidosis
b. Impaired hepatic detoxification of portal blood
c. Splenomegaly-induced anemia
d. Copper intoxication
e. Vitamin B
12
deficiency
A
b. Impaired hepatic detoxification of portal blood
4
Q
- This patient survives with his disorder for 2 years. At the time of
death, he would be expected to exhibit changes in which type of brain cells?
a. Oligodendrocytes
b. Striatal neurons
c. Pigmented cells of the substantia nigra
d. Astrocytes
e. Inferior olivary neurons
A
d. Astrocytes
5
Q
- The cerebrospinal fluid (CSF) protein content with either uremic
encephalopathy or hypertensive encephalopathy is likely to be
a. Abnormally low
b. Normal
c. Elevated to less than 100 mg /dL
d. Elevated to between 500 and 1000 mg /dL
e. Greater than 2000 mg /dL
A
c. Elevated to less than 100 mg /dL
6
Q
Items 6–8
A 65-year-old man has had many years of deteriorating kidney func-
tion due to diabetes. At age 59, dialysis was begun because of electrolyte
abnormalities.
- The most common neurologic complication of chronic renal failure is
a. Peripheral neuropathy
b. Delirium
c. Seizures
d. Dementia
e. Labile affect
A
a. Peripheral neuropathy
7
Q
- As the patient becomes uremic, he tends to develop the restless legs
syndrome. This may be controlled with
a. Haloperidol
b. Clonazepam
c. Caffeine
d. Nifedipine
e. Rifampin
A
e. Rifampin
8
Q
8. The most reliable treatment for the peripheral neuropathy of chronic renal failure is a. Thiamine supplements b. Clonazepam c. Phenytoin d. Minoxidil e. Renal transplant
A
b. Clonazepam
9
Q
9–12
A 68-year-old man presents with acroparesthesia, sensory ataxia, mem-
ory loss, and impotence. On exam, there are upper motor neuron signs in all
four extremities. He also has anemia and a sore tongue. Eventually vitamin B12
deficiency is diagnosed.
9. For vitamin B12 to be absorbed, it must bind to a. A cyanide atom and form cyanocobalamin b. An intrinsic factor c. The parietal cells of the stomach d. The ileal mucosa e. The jejunal mucosa
A
b. An intrinsic factor
10
Q
10. With vitamin B 12 deficiency, which of the following accumulates in the blood? a. Cysteine b. Methylmalonic acid c. Methionine d. Succinic acid e. Propionic acid 12
A
e. Propionic acid
11
Q
11. The patient with impaired vitamin B absorption is likely to develop a positive Romberg test because of damage to which of the following? a. Cerebellar vermis b. Cerebellar hemispheres c. Spinal cord lateral columns d. Basal ganglia e. Spinal cord posterior columns
A
e. Spinal cord posterior columns
12
Q
202. The type of visual field cut most often seen with vitamin B 12 deficiency is a a. Centrocecal scotoma b. Homonymous hemianopsia c. Bitemporal hemianopsia d. Binasal hemianopsia e. Hemianopsia with central sparing
A
a. Centrocecal scotoma
13
Q
202. The type of visual field cut most often seen with vitamin B 12 deficiency is a a. Centrocecal scotoma b. Homonymous hemianopsia c. Bitemporal hemianopsia d. Binasal hemianopsia e. Hemianopsia with central sparing
A
a. Centrocecal scotoma
14
Q
1. In Tay-Sachs disease, the enzymatic abnormality responsible for the neurologic deficits is deficiency of a. Hexosaminidase A b. Glucocerebrosidase c. Phosphofructokinase d. Glucose phosphorylase e. Sphingomyelinase
A
a. Hexosaminidase A
a. Hexosaminidase A
a. Hexosaminidase A
15
Q
- A 42-year-old woman is being treated with methotrexate for Wegener’s
granulomatosis. She is at risk for megaloblastic anemia and peripheral neuropathy
because methotrexate
disturbs the metabolism of
a. Cobalamin
b. Iron
c. Copper
d. Pyridoxine
e. Folate
A
e. Folate
16
Q
14–16
A 37-year-old woman develops cholecystitis and requires cholecystec-
tomy. Her family advises the physicians involved that she has a long history
of alcoholism and benzodiazepine use, including diazepam (Valium),
lorazepam (Ativan), and clonazepam (Klonopin). Approximately 7 days
after the surgery, the patient becomes increasingly agitated, delusional, and
suspicious. Routine investigations reveal no evidence of focal or systemic
infection. Hepatic, renal, and hematologic parameters are largely normal.
Within 24 h of these cognitive and affective changes, the patient has a generalized
tonic-clonic seizure. Magnetic resonance
imaging (MRI) and computed tomography
(CT) studies of the brain are normal, and her CSF is unremarkable.
- In consideration of the abuse history provided by the family, medica-
tion orders prior to the surgery should have included
a. Haloperidol
b. Chlorpromazine
c. Trihexyphenidyl
d. Prochlorperazine
e. Thiamine
A
e. Thiamine
17
Q
- The patient’s neurologic deterioration was most probably caused by
a. A delayed anesthetic reaction
b. Benzodiazepine withdrawal
c. Alcohol withdrawal
d. Unreported cocaine use
e. Idiopathic epilepsy
A
b. Benzodiazepine withdrawal
18
Q
- In anticipation of the seizures and cognitive deterioration that might
occur postoperatively, the physician involved would have been wise to
a. Consult a psychiatrist and neurologist prior to surgery
b. Provide intravenous alcohol supplements postoperatively to blunt the alcohol
withdrawal
c. Provide intramuscular or oral chlordiazepoxide several times daily at a dose
dictated by the patient’s level of agitation
d. Start phenytoin as a single dose nightly
e. Delay surgery until the risk of neurologic problems abated
A
c. Provide intramuscular or oral chlordiazepoxide several times daily at a dose
dictated by the patient’s level of agitation
19
Q
Items 17–23 For each clinical scenario, select the nutritional deficiency that is most likely responsible. a. Deficiency amblyopia b. Vitamin B6 deficiency c. Pyridoxine (vitamin B12) deficiency d. α tocopherol (vitamin E) deficiency e. Vitamin D deficiency f. Thiamine (vitamin B1) deficiency g. Nicotinic acid deficiency h. Kwashiorkor i. Vitamin C deficiency
- A 26-year-old man develops hemoptysis and dyspnea over the
course of 3 months. His physician suspects tuberculosis and starts him on
triple therapy with isoniazid (isonicotinic acid hydrazide), rifampin, and
ethambutol. After 1 month of treatment, the patient’s liver enzymes show
slight elevations, but the treatment is continued. The hemoptysis stops by
2 months, but the patient complains of pins-and-needles sensations in his
feet. Neurologic examination reveals hypoactive deep tendon reflexes in
the legs and slightly impaired position sense. Strength is good in all limbs.
A
c. Pyridoxine (vitamin B12) deficiency
20
Q
- A 50-year-old woman is found wandering in the street and is brought
to the emergency room by the police. She is disoriented to time, place, and
person, but has no evidence of head trauma. She staggers when she tries to
walk, but she has no detectable alcohol in her blood. Eye movements are
abnormal with paresis of conjugate gaze, and horizontal nystagmus is
apparent. Relatives are contacted, and they report that this woman has a
long history of alcohol abuse.
A
f. Thiamine (vitamin B1) deficiency
21
Q
19. A 46-year-old man complains of progressive visual problems. He notices problems with discriminating objects both up close and far away. His deficits have progressed over the course of 3 months. He has a 12-year history of pipe smoking, a 14-year history of daily aspirin use, and a 20year history of alcohol intake. He usually drinks 4 oz of gin daily. Examination reveals enlargement of the physiologic blind spot to the point where it extends into central vision.
A
g. Nicotinic acid deficiency
22
Q
20. A 32-year-old South African woman develops irritability, sleeplessness, and fatigue. Her family believes that she is depressed, but neurologic assessment establishes prominent short- and long-term memory problems. She has anemia and an obvious dermatitis on her face. Her diet is strictly vegetarian and limited almost entirely to grains, such as corn.
A
a. Deficiency amblyopia
23
Q
21. A 61-year-old man develops progressive cramping of his legs and a pins-and-needles sensation in his feet over the course of 1 year. He consults a physician when he notices paresthesias in his hands and unsteadiness of his gait. His family reports that he has had some urinary incontinence, but was too embarrassed to report it. On examination, he has a spastic paraparesis with severe disturbance of position and vibration sense in his legs. Despite obvious spasticity in the legs, the deep tendon reflexes are absent at
the knees and ankles. Peripheral blood smear reveals hypersegmented
polymorphonuclear leukocytes.
A
b. Vitamin B6 deficiency
24
Q
- A 4-year-old boy develops progressive gait ataxia and limb weakness
over the course of 3 months. Neurologic assessment reveals diffusely absent
deep tendon reflexes, proximal muscle weakness, ophthalmoparesis, and
poor pain perception in the feet. Blood tests reveal elevated creatine phosphokinase
(CK)
levels
and
abnormally
high
serum
bilirubin
levels.
Further
investigations
of hepatic function reveal that the child has a cholestatic
hepatobiliary disorder, but there is no evidence of hepatic dysfunction sufficient
to cause an encephalopathy.
A
d. α tocopherol (vitamin E) deficiency
25
23. A 9-month-old girl from famine-stricken Ethiopia exhibits profound
apathy and indifference to her environment. She is afebrile and appears to
have no significant infections at the time of her initial evaluation. Her hair
is sparse, and slight edema is evident about her ankles. She is well below
the fifth percentile for height in her age group. With handling she becomes
irritable, but throughout her examination she exhibits little spontaneous
movement. Her mother reports having seen transient tremors in the girl’s
hands a few weeks earlier, but these abated after a few days.
h. Kwashiorkor
26
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Items 24–30
For each clinical scenario, select the most likely diagnosis.
a. Postictal state
b. Hypothyroidism
c. Uremic encephalopathy
d. Wernicke’s encephalopathy
e. Herpes encephalitis
f. Progressive multifocal leukoencephalopathy (PML)
g. Meningeal carcinomatosis
h. Central nervous system (CNS) toxoplasmosis
i. Multiple sclerosis
j. Hepatic encephalopathy
k. Subacute combined systems disease
l. Meningococcal meningitis
m. Subacute sclerosing panencephalitis (SSPE)
n. AIDS encephalopathy
o. Pickwickian syndrome
```
```
24. A 23-year-old woman with a history of hemophilia notices progressive
memory
difficulty.
She
has
required
little
hematologic
support,
but
she
did
receive
transfusion
of
factor
VIII
at
least
five
times
over
the
past
7
years.
Neurologic examination reveals word-finding difficulty, poor recent and
remote memory, gait ataxia, mild dysarthria, and a labile affect. Her right
plantar response is extensor and her left brachioradialis reflex is hyperactive
with
transient
clonus.
An
MRI
of
the
brain
is
unrevealing.
```
n. AIDS encephalopathy
27
25. A 35-year-old businessman complains of sleep attacks. He runs a
chain of dry cleaning stores, but does not usually work with the cleaning
fluids. He reports falling asleep several times during the workday, even at
business meetings and during interviews. He has developed the sleep
attacks only after gaining over 100 lb. His weight at the time of the examination
is 324 lb.
o. Pickwickian syndrome
28
```
6. A 19-year-old man develops obvious personality changes over the
course of 2 weeks. He becomes agitated with little provocation and abuses
his wife both verbally and physically. His behavior is sufficiently atypical
for it to prompt his relatives to seek psychiatric assistance for him. While
being interviewed by a psychiatrist, he becomes unresponsive and develops
generalized
convulsions
with
opisthotonic
posturing,
tonic-clonic
limb
movements,
and
urinary
incontinence.
He
is
hospitalized
for
investigation
of
his
seizure
disorder.
On
initial
examination,
he
is
noted
to
have
a
lowgrade
fever
and
a
mild
left
hemiparesis.
His
CSF
opening
pressure
is
210
mmH
O. His CSF cultures yield no growth, and his EEG reveals polyspikeand-wave
discharges
```
originating in the right temporal lobe. A CT of his
brain reveals focal swelling of the right temporal lobe.
e. Herpes encephalitis
29
27. A previously healthy 25-year-old woman develops acute loss of
vision in her left eye. She awakens with pain in the eye and reduction of her
acuity to perception of light and dark. She delays seeing a physician for 1
week, during which time her acuity gradually improves sufficiently to
allow her to read. On examination, the physician discovers she has slurred
speech and poor rapid alternating movements with the left hand. Ocular
dysmetria is evident in both eyes. Her tandem gait is grossly impaired. The
physician obtains an EEG, which is normal.
i. Multiple sclerosis
30
8. A 17-year-old man complains of headache and photophobia on
awakening. His physician discovers a low-grade fever and resistance to
neck flexion. The physician advises the patient to take acetaminophen
and remain in bed for the next 24 h. Within 12 h, the patient develops
nausea and more intense headache. He seems disoriented and inappropriately
lethargic. His family brings him to an emergency room. The
emergency room physician notes a petechial rash on the legs and marked
neck stiffness. CSF examination reveals a glucose content of 5 mg/dL,
protein content of 87 mg/dL, and cell count of 112 leukocytes, with 70%
polymorphonuclear cells.
l. Meningococcal meningitis
31
9. A 56-year-old man is struck over the parietal area of the head during
a robbery. He loses consciousness for 35 min but has no focal weakness or
numbness on recovering consciousness. Within 2 days of the incident, his
wife finds him unresponsive in bed early in the morning. She calls for an
ambulance, but before it arrives her husband becomes more alert and asks
for something to eat, saying he wants to have some supper before he goes
to bed for the night. The ambulance attendant first on the scene notes that
the patient is disoriented to place and time and has weakness of his right
arm and leg.
a. Postictal state
32
0. A 35-year-old woman is found unconscious on the floor of her
apartment. A bottle of cleaning fluid is found on a table near her. One of
the contents indicated in the fluid is carbon tetrachloride. The ambulance
crew notes that the patient is breathing independently, but her breath has
a distinctly fetid odor unlike that associated with the cleaning fluid. Her
limbs are flaccid, and she groans when she is moved. She responds to
no inquiries and is poorly responsive to pain. A serum ammonia level
obtained at the emergency room is 250 mg/dL, triple the normal level.
EEG reveals triphasic waves, most prominently over the front of the head.
j. Hepatic encephalopathy
