Download Myasthenia gravis and Muscular diseases Part One: Each item

Myasthenia gravis and Muscular diseases
Part One: Each item below contains a question or incomplete
statement followed by suggested responses. Select the one best
response to each question.
1. Myasthenia gravis cholinergic crisis is due to
a. Anti acetylcholinesterase drug overdose
b. Esterase activity disappeared
c. Anti Che drug dosage is insufficient
d. Anti Che drug action suddenly disappeared
e. Anti acetylcholinesterase drug allergy
2. Which basis does not support the myasthenia gravis clinical？
a. Limbs after motion is easy to strain
b. Volatility ptosis and diplopia
c. The morning light both heavy limbs weakness
d. Low frequency electrical stimulation point attenuation is more than
10%
e. Fatigue test symptoms without improved after the break
3. Low blood potassium periodic paralysis of the clinical manifestations,
which is the right one?
a. Is more common in elderly patients
b. Cranial nerve damage
c. Symmetry retardation paralysis
d. Tendon reflex
e. Positive pathologic reflex
4. The rash typically associated with dermatomyositis is characterized by
which of the following?
a. Adenoma sebaceum
b. Shagreen patches
c. Target-shaped erythematous lesions on the extremities
d. A purplish discoloration around the eyes
e. Telangiectasias
5. A 65-year-old man was diagnosed with lung cancer 6 months ago. Over
the past 2 months, he has had worsening severe proximal muscle
weakness. He is most likely to have which of the following?
a. Dermatomyositis
b. Trichinosis
c. Multiple sclerosis (MS)
d. Progressive multifocal leukoencephalopathy (PML)
e. Myasthenia gravis
6. A 2-year-old male child has recently been diagnosed with muscular
dystrophy. The parents are highly educated people, but not in the medical
field. They have many specific and detailed questions. Which abnormal
gene is responsible for the pathology of Duchenne muscular dystrophy?
a. Glucose-6-phosphatase
b. Hexosaminidase B
c. Myosin
d. Dystrophin
e. Actin
7. A 67-year-old woman has noticed blurry vision and weakness over the
past 4 months. Her symptoms are always worse toward the end of the day.
She undergoes a neuromuscular evaluation, including electromyography,
and the diagnosis of myasthenia gravis is made. Which of the following is
the most obvious site of disease in myasthenia gravis?
a. Anterior horn cell
b. Neuromuscular junction
c. Sensory ganglion
d. Parasympathetic ganglia
e. Sympathetic chain
8. A patient with amyotrophic lateral sclerosis develops progressive
difficulty breathing. His cough becomes totally ineffective for clearing
his airway, and he requires a tracheostomy. Facial muscle weakness and
fasciculations are obvious at the time the tracheostomy is performed.
Which of the following is the most appropriate treatment for this patient?
a. Atropine sulfate
b. Pyridostigmine
c. Edrophonium
d. Amantadine
e. Chest physical therapy
9. A 28-year-old woman has the clinical diagnosis of myopathy and
undergoes a muscle biopsy for diagnosis. The pathology demonstrates an
inflammatory muscle disease characterized by non-caseating granulomas.
Which of the following may have caused her symptoms?
a. Cysticercosis
b. Tuberculosis
c. Sarcoidosis
d. Schistosomiasis
e. Carcinomatosis
10. A 62-year-old woman has limb discomfort and trouble getting off the
toilet. She is unable to climb stairs and has noticed a rash on her face
about her eyes. On examination, she is found to have weakness about the
hip and shoulder girdle. Not only does she have a purplish-red
discoloration of the skin about the eyes, but she also has erythematous
discoloration over the finger joints and purplish nodules over the elbows
and knees. Which of the following is the most likely diagnosis?
a. Systemic lupus erythematosus
b. Psoriasis
c. Myasthenia gravis
d. Dermatomyositis
e. Rheumatoid arthritis
11. A 32-year-old woman has several family members with Duchenne
dystrophy. She has genetic testing and is known to be a carrier of the gene.
A blood test may exhibit substantial elevations in her serum of which of
the following?
a. Ammonia
b. Myoglobin
c. Phosphofructokinase
d. Creatine phosphokinase (CPK)
e. Hexosaminidase
12. Duchenne dystrophy affects approximately what percentage of
infants?
a. 1 in 3,000 infants
b. 1 in 3,000 male infants
c. 1 in 30,000 infants
d. 1 in 30,000 male infants
e. 1 in 50,000 infants
13. A 2-year-old male child has recently been diagnosed with muscular
dystrophy. The parents are highly educated people, but not in the medical
field. They have many specific and detailed questions. For a female child
to have Duchenne dystrophy, she must have which of the following？
a. Turner syndrome (XO)
b. Klinefelter syndrome (XXY)
c. Two affected parents
d. An affected father
e. An affected brother
14. A biopsy is obtained from a clinically affected muscle in a person
with several months of progressive weakness. The pathologist reports that
there are numerous abnormally small muscle fibers intermingled with
hypertrophied muscle fibers. The normal mosaic of muscle fiber types is
disrupted. There is no significant inflammatory infiltrate. This pathologic
description is most consistent with which of the following?
a. Disuse atrophy
b. Denervation atrophy
c. Muscular dystrophy
d. Polymyositis
e. Hypoxic damage
15. A 52-year-old left-handed woman says that she has a history of
myasthenia gravis. When asked about details of the history she says that
she was weak. With further prompting the patient becomes belligerent
and says that she does not remember any further details. Which of the
following is the most common manifestation of muscle weakness with
myasthenia gravis?
a. Diaphragmatic weakness
b. Wristdrop
c. Footdrop
d. Ocular muscle weakness
e. Dysphagia
16. A patient with amyotrophic lateral sclerosis dies within 9 months of
his initial evaluation. An autopsy is performed, but only the central
nervous system (CNS) can be examined. Examination of the spinal cord
would be expected to reveal degeneration of which of the following?
a. Dorsal root ganglia
b. Posterior columns
c. Spinothalamic tracts
d. Corticospinal tracts
e. Spinocerebellar tracts
17. The shortest life expectancy is associated with which clinical sign in
amyotrophic lateral sclerosis?
a. Atrophy of the interossei
b. Atrophy of the gastrocnemius
c. Fasciculations in the lumbrical muscles
d. Atrophy of the pectoralis muscles
e. Fasciculations in the tongue
(18～20 common topic)
Male, 35 years old, weight loss, fatigue, afraid of hot, hand tremors 2
months, night suddenly appeared lower extremity flaccid paralysis,
emergency check: conscious, 40/80mmHg, heartbeat 108/min, the law is
neat, slightly enlarged thyroid. No vascular murmur.
18. Causes the patient to be the direct cause of the double lower limb soft
paralysis may be
a. Cerebral embolism
b. Motor neuron disease
c. Myasthenia gravis
d. Respiratory base poisoning
e. Blood potassium anomaly
19. In order to clear the diagnosis, which inspection item should be the
first to carry out?
a. Head CT, blood glucose determination
b. Electromyography and blood electrolyte determination
c. Chest CT and blood anti acetylcholine receptor antibody
determination
d. Blood gas analysis and blood electrolyte determination
e. Determination of serum electrolytes and thyroid function
20. Which of the emergency treatment of the patient should be?
a. Spironolactone
b. Correcting electrolyte disorder
c. Intravenous infusion of potassium chloride and insulin
d. Glucocorticoid therapy
e. Dehydration and reduction of intracranial pressure
Part Two: Fill in the blanks
1. Commonly used antibiotics in the treatment of myasthenia gravis, the
anticholinesterase drug has _________
2. The pathogenesis of myasthenia gravis is related to _________
3. Myasthenia gravis involved muscle often: _________
4. The main death cause of myasthenia gravis: _________
5. Tests for the diagnosis of myasthenia gravis include:
_________
_________
6. Myasthenia gravis is divided into three types: _________ _________
_________
7. Myasthenia gravis is a major cumulative neuromuscular joint
_________ on post synaptic membrane of autoimmune diseases
8. The skeletal muscle fatigue characteristics of Myasthenia gravis is:
_________
9. Type hypo kalmia periodic paralysis of the main features are:
_________ _________
10. The complications of myasthenia gravis: _________ _________
_________
Part Three: Definitions
1. Muscle tone
2. Spasticity
3. Periodic paralysis
4. Myasthenia gravis (MG)
5. Muscular dystrophies
Part Four: General questions
1. Grading muscle power
2. What are cerebellar dysfunction signs?
3. Presenting symptoms in myasthenia gravis
4. How to diagnosis myasthenia gravis?
5. The subdivided of muscular dystrophies?
Part Five: Case analysis
A 30-year-old female plastic surgery resident presents with a 1-month
history of intermittent ptosis (droopiness of the eyelids) and fatigue. She
has been on call every third night over the past 2 months and has been
attributing her fatigue to her hectic call schedule. However she became
concerned when she acutely developed ptosis last month after being on
call. She went home and went to sleep, and by morning her ptosis had
resolved. Her 6-year-old triplets have pointed out to her that she can’t
keep up with them when they’re riding their bicycles. She had
experienced three more episodes of ptosis over the past month. They all
have occurred while she has been post call and have improved by the
morning. Today for the first-time she developed ptosis while performing a
complicated facial lift. Her attending asked her to stop assisting in
surgery and to immediately seek medical evaluation. She has not
experienced diplopia, dysarthria, dysphagia, difficulty walking up stairs,
difficulty blow-drying her hair, or shortness of breath. She had always
been healthy until now. Her neurologic examination is notable for normal
mental status and speech. Her cranial nerve examination reveals bilateral
ptosis on primary gaze, which worsens with sustained upward gaze for 90
seconds. Extraocular muscles are intact as is her facial strength. Her
motor strength is normal with the exception of 4+/5 in the deltoid muscles
bilaterally. On repetitive testing of the right iliopsoas muscle fatigability
is elicited, which improves after 2 minutes of rest. Her sensory
examination and deep tendon reflexes are normal.
1. What is the most likely diagnosis?
2. What is the best test to confirm the diagnosis?
3. What is the next step in therapy?
Answers
Part One: Choice question
1 to 5: a d c d a
6 to 10: d b e c d
11 to 15: d b a b d
16 to 20: d e e e b
Part Two: Fill in the blanks
1. Pyridostigmine bromide
2. The AChR damage induced by auto-antibodies.
3. One side or both sides of the eye muscle paralysis
4. Respiratory muscle involvement
5. Jolly test, anti-drug test
6. Myasthenic crisis, cholinergic crisis, brittle crisis.
7. Acetylcholine receptors
8. Light night heavy in the morning.
9. Slow skeletal muscle recurrent palsy, attack lower serum potassium.
10. Myasthenia gravis crisis, respiratory failure, muscular dystrophy.
Part Three: Definitions
1. Muscle tone: For clinical purposes, tone can be defined as the
resistance of muscle to passive movement of a joint. Tone depends on the
degree of muscle contraction and on the mechanical properties of muscle
and connective tissue.
2. Spasticity: Consists of a fincrease in tone that affects different muscle
groups to different extents.
3. Periodic paralysis: Periodic paralysis is a group of rare genetic
diseases that lead to weakness or paralysis (rarely death) from common
triggers such as cold, heat, high carbohydrate meals, not eating, stress or
excitement and physical activity of any kind. The underlying mechanism
of these diseases are malfunctions in the ion channels in skeletal
musclecell membranes that allow electrically charged ions to leak in or
out of the muscle cell, causing the cell to depolarize and become unable
to move (a channelopathy).
4. Myasthenia gravis (MG): Myasthenia gravis is a neuromuscular
disease that leads to fluctuating muscle weakness and fatigue. In the most
common cases, muscle weakness is caused by circulating antibodies that
block nicotinic acetylcholine receptors at the postsynaptic neuromuscular
junction.
5. Muscular dystrophies: The muscular dystrophies are a group of
inherited myopathic disorders chare]acterized by progressive muscle
weakness and wasting.
Part Four: General questions
1. Grading muscle power：
5 normal powers
4 Active movements against resistance and gravity
3 Active movements against gtavity but not resistance
2 Active movements possible only with gtavity eliminated
1 Flicker or trace of contration
0 No contraction
2. What are cerebellar dysfunction signs?
Hypotonia
Depressed or pendular tendon reflexes
Ataxia
Gait disorder
Imbalance of station
Disturbances of eye movement
Dysarthria
3. Presenting symptoms in myasthenia gravis
Diplopia
Ptosis
Dysarthria
Lower extremity weakness
Generalized weakness
Dysphagia
Upper extremity weakness
Masticatory weakness
4. How to diagnosis myasthenia gravis?
The diagnosis of myasthenia gravis can generally be confirmed by the
benefit that follows administration of anticholinesterase drugs; the power
of affected muscles is influenced at a dose that has no effect on normal
muscles and slight, if any, effect on muscles weakened by other causes.
5. The subdivided of muscular dystrophies:
Duchenne dystrophy
Becker dystrophy
Gmery-Dreifuss muscular dystrophy
Limb-Girdle dystrophy
Facioscapulohumeral dystrophy
Distal myopathy
Ocular dystrophy
Oculopharyngeal dystrophy
Paraspinal dystrophy
Part Five: Case analysis
Most likely diagnosis: Myasthenia gravis
Best confirmatory test: Antiacetylcholine receptor antibodies
Next step in therapy: Acetylcholinesterase inhibitors (pyridostigmine) and
immunosuppression