Lec 15: Diseases of the Nerve and Muscle Flashcards
(27 cards)
characterized by tea-colored or pinkish urine secondary to rhabdomyolysis.
myoglobinuria
Sustained contraction or loss of relaxation upon exertion.
myotonia
Used to detect dystrophin in 60% of cases especially if patient has suspected muscle dystrophy.
Multiplex PCR
Most common congenital muscular dystrophy in Europe and is due to absence of lamina alpha-2
Merosin-deficient Congenital Muscular Dystrophy
DMD or BMD? (Duchenne/Becker Muscular Dystrophy?)
No dystrophin staining after immunohistochemistry
DMD
*In BMD, dystrophin is patchy
DMD or BMD? (Duchenne/Becker Muscular Dystrophy?)
milder
BMD
*Life span can be up to 30y/o whereas only 20 in DMD.
DMD or BMD? (Duchenne/Becker Muscular Dystrophy?)
CNS involvement is rarer and no mental retardation among patients.
BMD.
- BMD generally has milder symptoms than DMD.
TRUE or FALSE: Myotonia dystrophica can be associated with insulin deficiency.
TRUE.
A distal dominant pattern of weakness is characteristic of:
a. TYPE 1 Myotonic Dystrophy
b. TYPE 2 Myotonic Dystrophy
c. BOTH
d. NOTA
a. TYPE 1 Myotonic Dystrophy
CTG trinucleotide repeats in DMPK gene (chromosome 19)
a. TYPE 1 Myotonic Dystrophy
b. TYPE 2 Myotonic Dystrophy
c. BOTH
d. NOTA
a. TYPE 1 Myotonic Dystrophy
Facial muscle is rarely involved.
a. TYPE 1 Myotonic Dystrophy
b. TYPE 2 Myotonic Dystrophy
c. BOTH
d. NOTA
b. TYPE 2 Myotonic Dystrophy
Autosomal-Dominant Inheritance pattern.
a. TYPE 1 Myotonic Dystrophy
b. TYPE 2 Myotonic Dystrophy
c. BOTH
d. NOTA
c. BOTH
All of the following disorders have Autosomal-Dominant inheritance pattern, EXCEPT:
a. Myotonia Congenita (Becker)
b. Andersen’s syndrome
c. Paramyotonia congenital
d. Potassium-aggravated myotonia.
a. Myotonia Congenita (Becker)
Which of the following is characterized by potassium channel disorder?
a. Myotonia Congenita (Becker)
b. Andersen’s syndrome
c. Paramyotonia congenital
d. Potassium-aggravated myotonia.
b. Andersen’s syndrome.
- Myotonia Congenita (Becker) - Chloride channel disorder
- Paramyotonia Congenita - Sodium channel disorder
- Potassium-Aggravated myotonia - Sodium channel disorder
The following drugs are used in the treatment of Paramyotonia congenita, EXCEPT:
a. acetazolamide
b. mexiletine
c. salbutamol
d. NOTA
d. NOTA
TRUE or FALSE: Hyperkalemic periodic paralysis is a Sodium Channel disease.
TRUE.
- The mutation in Na-channel causes inactivation of the Na gate hence allowing increased Na influx. As a compensatory mechanism, K+ efflux occurs (exits the cell) causing an increased K (hyperkalemia).
TRUE or FALSE: Hypokalemic Periodic paralysis is a Potassium Channel Disease.
FALSE. Hypokalemic periodic paralysis is a CALCIUM CHANNEL disease.
Mutation of Ca or Na gene -> selectivity of Ca and Na of ion pores disappear -> allows entrance of proton -> more acidic -> inhibits K channel -> K can’t go out and is concentrated in the cell -> hypokalemia outside -> weakness
Mutation in this gene predisposes one to Malignant hyperthermia.
RyR1
A dramatic and often fatal condition characterized by rapid and sustained rise in temperature during generalized anesthesia associated with generalized muscle rigidity, tachycardia, tachypnea and cyanosis, leading to rhabdomyolysis (may lead to renal failure & death)
Malignant hyperthermia
Treatment for malignant hyperthermia
Dantrolene sodium
The best way to diagnose Mitochondrial diseases:
muscle biopsy
Most common symptoms of mitochondrial myopathy.
MELAS and CPEO
Mitochondrial myopathy, Lactic Acid and Stroke-like symptoms & Chronic Progressive External Ophthalmoplegia
Histologic findings of this condition include endomysial inflammation, rimmed vacuoles and tubofilaments.
Inclusion Body Myositis
The hallmark of Dermatomyositis.
Perifascicular atrophy
- due to ischemia
