Quiz 06/23/2022 (1)

A 5-year-old male presents because of muscle stiffness. His symptoms are worse during the colder winter months and with gym class at school. He sometimes becomes so stiff he can hardly breathe. Examination shows no muscle atrophy or hypertrophy but myotonia is present. Upon further questioning, you learn he has an older brother with similar symptoms. What is the likely dysfunctional gene in this patient?

Which of the following is seen on muscle biopsy in patients with steroid myopathy?

Which of the following is the antibody associated with dermatomyositis that is known to confer the highest risk of cancer?

Based on the findings on the muscle biopsy (trichrome stain) shown below, which of the following is most likely seen on examination of this patient?

You are evaluating a 1-year-old who has had delayed motor development and diffuse weakness since birth and presents now to the hospital for a first-time seizure. The physical exam is notable for 3/5 deltoid abduction, 4-/5 hip abduction, 4-/5 hip flexion, and 4-/5 hip extension. He is unable to walk but is meeting cognitive milestones. An MRI brain is done and shows diffuse scattered T2 FLAIR white matter hyperintensities.

If genetic testing is performed, a mutation in which of the following genes would be most expected?

A 42-year-old man with a 6-month history of progressive muscle weakness has a nerve biopsy performed. Based on the toluidine blue (left) and trichrome (right) stain slides shown, which of the following is the most likely diagnosis?

This muscle biopsy is most consistent with which myopathic disease?

Which of the following medications, when taken alongside statin therapy, increases the risk of statin-induced myopathy?

This muscle biopsy is most consistent with which myopathic disease? 

Which of the following is the most classic finding of early inclusion body myositis?

A 57-year-old male with recently diagnosed small cell lung cancer (SCLC) is presenting to the electromyography lab with a one-month history of muscle cramps and muscle pain. Percussive myotonia is appreciated on examination. Electromyography showed myokymic discharges. Autoantibodies against which of the following channels are likely present in this case?

Congenital muscular dystrophies are most often associated with which of the following pathophysiologies?

Parents bring their 3-year-old son to the clinic for difficulty walking. On examination, the patient has a waddling gait and enlarged calf muscles. When rising from a seated position he has to rely extensively on his arms to stand up. Which of the following is the most likely inheritance pattern of the genetic disorder affecting this patient?

A 20-year-old male presents to your clinic for weakness. He is the star baseball player at the local university, but during the season his batting average has been dropping, and he finds he is having trouble standing on his toes, performing overhead shoulder presses, and more recently ascending steps. You give him a script for some blood testing and an EMG/NCS and schedule a follow-up in 2 weeks.

Unfortunately, shortly after returning home he had a fall down a flight of stairs and sustained a compound radius fracture. He was taken to the emergency room where an open reduction and fixation (ORIF) was performed. Shortly after the surgery, he developed tachycardia, tachypnea, and masseter muscle contractions, which then progressed to fever and rigidity.

Which of the following test results is most likely to be seen in this patient?

A four-year-old boy with no significant past medical history is brought to your clinic due to difficulty walking. His mother states that he began walking at 12 months of age, but in the past few months, he seems to be more fatigued and weak when walking. On physical exam, his calves seem to be abnormally large. This disorder is caused by what mutation?

A 45-year-old man with a past medical history of cardiac arrhythmia requiring pacemaker placement is referred to the clinic with a twenty-five-year history of slowly-progressive bilateral ptosis and diplopia. On examination, he has bilateral ptosis, decreased range of motion of the extraocular muscles, and mild proximal weakness in his upper and lower extremities. Which of the following is the most likely diagnosis?

A 47-year-old female presents to the clinic with the chief complaint of slowly progressive proximal muscle weakness. Electromyography showed short duration, low amplitude motor unit action potentials. A muscle biopsy was performed and shown below. A diagnosis is made and the patient is started on a therapeutic agent. What is the most likely medication initiated?

A 65-year-old man comes to the clinic with a one-year history of difficulty walking. More recently, he has also noticed a tendency to drop things. On examination, he was found to have weakness in his bilateral lower limbs, predominantly in his quadriceps muscles, along with finger flexion weakness that is worse on the left side. His sensory examination was normal. Which of the following is the most likely diagnosis?

Eteplirsen is an effective treatment in patients with Duchenne muscular dystrophy (DMD) that have which of the following dystrophin mutations?

This muscle biopsy is most consistent with which myopathic disease?

A 47-year-old female presents to the clinic with the chief complaint of slowly progressive proximal muscle weakness. Electromyography showed short duration, low amplitude motor unit action potentials. A muscle biopsy was performed and shown below. A diagnosis is made and the patient is started on a therapeutic agent. What is the most likely medication initiated?

A 57-year-old male with recently diagnosed small cell lung cancer (SCLC) is presenting to the electromyography lab with a one-month history of muscle cramps and muscle pain. Percussive myotonia is appreciated on examination. Electromyography showed myokymic discharges. Autoantibodies against which of the following channels are likely present in this case?

Which of the following medications is effective in the treatment of myotonia?

Which of the following is seen on muscle biopsy in patients with steroid myopathy?

Congenital muscular dystrophies are most often associated with which of the following pathophysiologies?

This muscle biopsy is most consistent with which myopathic disease?

This pathology slide is most consistent with which of the following diseases?

A 27-year-old female with a history of cataracts and an unknown family history was referred to the neurology clinic for excessive daytime sleepiness. On examination facial weakness and grip myotonia were appreciated. Genetic testing revealed a mutation in the DMPK gene. Based on her diagnosis, which of the following tests should be performed annually?