Peds - Neuromuscular Disease Flashcards
acquired vs hereditary?
GBS, AIDP, polio, botulism, MG, polymyositis, toxic neuropathy
acquired.
Pseudohypertrophy- define and name two common associated diseases
Def: increased gastrocnemius calf circumference caused by increase in fat and connective tissue, not true muscle
DMD, becker’s muscular dystrophy
_______ appearance is focal atrophy of distal lower extremity muscles particularly seen in hereditary motor sensory neuropathies
stork (or champagne bottle) leg appearanc
_____ is the inability to rise from sitting position on the floor, normally due to proximal (pelvic girdle) muscle weakness
Gower’s sign
Toe walking seen in DMD, is caused by
fibrosis
Duchenne muscular dystrophy is a _____ inheretence and results from abnormality in the ____ gene loci and ______ deficiency
X-linked recessive
Xp21 gene loci
plasma membrane protein dystrophin deficiency
– absent dystrophin or less than 3% of normal is diagnostic of DMD.
All DMD subjects who took > or = 9 seconds to ambulate _____ feet lost ambulation within 1 year
30 feet
Which part of PFTs is a prognostic factor for DMD
forced vital capacity (FVC) - increases during the first decade of life and plateaus during the early part of the second decade. Linerar decline of FVC between age 10 to 20 years old. FVC <40% is a contraindication to surgical spinal arthrodesis bc of increased perioperative morbidity
In beckers muscular dystrophy, _____ is present but has abnormal molecular weight
dystrophin is present 20-80% of the time, but is abnormal. Also X-linked
Which type of congenital muscular dystrophy has most intellectual retardation?
japan - Fukuyama type ( LY)
Which type of congenital muscular dystrophy has most hydrocephalus and fundal changes?
Satavuori type
inheretence of congenital muscular dystrophy?
autosomal recessive , gene 9q31-33; 6q
can be sporadic or a sequel to viral or other inflammatory process
facioscapulohumeral muscular dystrophy often affects what facial muscles?
orbicularis oculi, zygomaticus, and orbicularis oris.
masseter, temporalis, extraocular and pharyngeal muscles are spared usually
inheritence of facioscapulohumeral muscular dystrophy
AD
gene locus 4q35
emery-dreifuss muscular dystrophy (EMD) can present in adolescence or early adulthood with atrophy in upper arms and legs due to focal wasting of ____ and ____
biceps and calf muscles
Clinical hallmark of emery-dreifuss muscular dystrophy (EMD)?
early presence of contractures of elbow flexors with limitation of full elbow extension. Heel cord tightness with ankle dorsiflexion weakness and toe walking may also be present
inheritence of emery-dreifuss muscular dystrophy? (EMD)
X-linked recessive, gene locus Xq28
EMERIN is muscle protein deficient as opposed to dystrophin in DMD/BMD
Inheretence of limb girdle syndromes
Auto recessive - gene 15q
symptoms very similar to DMD/BMD
Which congenital myopathy?
- AD with gene locus 19q13.1
- high incidence of malignant hyperthermia with inhalation of anesthetic agents
- predominance of type I muscle fibers (high-oxidative, low-glycolytic) and paucity of TypeII fibers resulting in relative deficiency of glycolytic enzymes
- mild relatively non-progressive weakness
central core myopathy
Which congenital myopathy?
- autosomal recessive;
- predominance of Type I fiber involvement
- delayed motor development, hypotonia, nonprogressive symmetric weakness of trunk and proximal limbs, diaphragmatic weakness with risk of *nocturnal hypoventilation
Minicore disease
Which congenital myopathy?
- autosomal recessive and AD
AD gene has been localized to ch 1q21-q23
mild nonprogressive myopathy with hypotonia and proximal weakness
nemaline myopathy (rod-body myopathy)
Which congenital myopathy?
- Can be AD/AR or X-linked (Xq28)
- xentronuclear myopathy (muscle fiber nuclei found at the center of the cell as opposed to the periphery where they are usually found)
- AR present with hypotonia, delay in motor milestones, generalized weakness of proximal and distal musculature, and ptosis with weakness of external ocular muscles and axial muscles
- X-linked inherited type presents iwth neonatal onset of severe generalized hypotonia, severe muscle weakness, dysphagia, and respiratory insufficiency, often requiring ventilator support at birth
myotubular myopathy
____ are muscular dystrophies that are characterized by delayed relaxation (sustained contraction) of muscles after contraction (myotonia).
Myotonic myopathies - including Myotonic muscular dystrophy, myotonia congenita, schwartz-jampel syndrome, congenital myotonic dystrophy
_____ is an AD muscular dystrophy with myotonia, muscle weakness/wasting, cataracts, premature balding, cardiomyopathy, conduction deficits, gonadal atrophy and variable intellectual deficits and dementia.
myotonic muscular dystrophy
inheretence of myotonic muscular dystrophy: steinerts disease or dystrophia myotonica
AD with marked clinical heterogeneity, gene 19q13
inheretence of friedreichs ataxia
AR - linked to chromosome 9q21
What is the protein abnormality in friedreichs ataxia?
mitochondrial protein called frataxin
wheelchair reliance becomes imminent when _____ strength becomes < than antigravity and time ________ is > 12 seconds ( in DMD)
knee extension strength
ambulate 30 feet
surgical intervention for management of scoliosis in NMD is prior to curvature of ______ and vital capacity falling to below _____
35 degrees
35%
_____ is the most effective treatment of progressive scoliosis
spinal arthrodesis
______ is an AD disorder inhereted as dominant or recessive trait in which myotonia is the onlyor predominant feature. Symptoms usually present after birth and exacerbated by prolonged rest or inactivity and cold. muscle hypertrophy is commonly seen. Can also see sustained eye closure in a crying infant
myotonia congenity Thomsens disease (little hercules)
normal muscle tone and function - myotonia following hand closure, eye-closure, ocular deviation, or other sustained movements.
myotonia congenita (thomsens disease aka little hercules) can overlap with ______ in some families
hyperkalemic periodic paralysis
gene of concern in myotonia congenita?
gene 7q35
myotonia congenity may benefit from these medications whensymptoms become disabling (5)
quinine
procainamide
phenytoin
corticosteroids
tocainide
_____ is an autosomal recessive disease with symptoms of hypotonia, *dwarfism, diffuse bone disease, narrow palpebral fissures and blepharospasm, micrognathia, and flattened facies. Symptoms are non-progressive
Schwartz-Jampel syndrome
______ is a type of mytonic dystrophy occuring in infants who are almost always born to mothers affected with myotonic dystrophy. It is characterized by severe hypotonia at birth, facial weakness, arthrogryposis,a nd variable breathing and swallowing difficulties
congenital myotonic dystrophy
Name the different types of myasthenia gravis
- transient - born to MG + moms and self-limiting in 2-3 weeks.
- Congenital/infantile - AR inheritance, AChR Ab are usually absent.
- Juvenile myasthenia - similar to adult AI type, high titer of AChR ab. Particularly affects adolescent girls and is often severe and labile.
- autoimmune
juvenile myasthenia shows fatigability of muscle (surface electrodes) after stimluation of peripheral nerve (surface electrodes) at _____ Hz
4 or 10 hz
In AI MG, repetitive nerve stimlulation studies show a characteristic decrement in compound motor action potential at slow stimulation rates(______hz) over a train of ____ stimuli. Decrements of > _____% are noted
2-5Hz
4-5 stimuli
10%
_____ presents with a prodromal respiratory or GI infection occuring within 1-month of onset. This often occurs with mycoplasma, CMV, EBV, campylobacter jejuni, and various vaccinations.
acute inflammatory demyelinating polyradiculoneuropathy (AIDP) also known as GBS
Name the four different types of hereditary motor sensory neuropathies (HMSN)
Type I (CMT I) 70-80% of cases presents with hypertrophic demyelinating neuropathy (onion bulbs) on nerve biopsy- 17p11.2-12
Type II (CMT II) axonal neuropathy with low amplitudes; inverted champagne leg or stork leg (calf and anterior compartment wasting)
Type III (Dejerine-Sottas disease) severe hypertrophic demyelinating polyneuropathy with onset in infancy or early childhood
Type IV (Refsum disease) autosomal recessive disorder; presents as weakness in distal extremities
Pathology?
anorexia, N/V, GI distubance, clumsiness, seizures, mental status changes, and papilledema. Weakness predominantly occurs inthe lower extremities
lead poisoning with toxic neuropathy
Spinal muscular atrophy Types I-IV are linked to _________gene on chromosome ____
autosomal recessive SMN1
5
Name the 4 types of SMA
I: at birth to 6 months (Werdnig-HOffman Disease - severe SMA)
II: 7-18 months
III: after 18 months
IV: adulthood
inheritence of SMA I - Werdnig-HOffman Disease
AR, gene 5q11-q13
seen as a characteristic picture of increased echo in muscle atrophy and increased subcutaneous space
SMA II - intermediate SMA
