Chapter 27- PNS Flashcards
What disorder should be thought of with heliotrope rash and malar rash
Dermatomyositis
What disorder can appear very similar to SLE with a positive ANA and hallmark of anti-jo-1 antibody
Dermatomyositis
What is the major characteristic of X-linked muscular dystrophy
Replacement of skeletal muscle by adipose tissue
What is the typically first presentation of X-linked muscular dystrophy
Proximal muscle weakness at 1 year of age
What disorder should be thought of with pseudohypertrophy, especially in calves
X-linked muscular dystrophy
What disorder is characterized as autoantibodies against postsynaptic Ach receptor at NMJ
Myasthenia gravis
What disorder is characterized by muscle weakness that worsens with use and improves with rest
Myasthenia gravis
What NMJ disorder is associated with thymic issues
Myasthenia gravis
What disorder is characterized by antibodies against presynaptic calcium channels at NMJ
Lambert-seton syndrome
What paraneoplastic syndrome is lambert-Eaton syndrome most commonly due to
Small cell carcinoma
How does lambert-Eaton syndrome resolve
Resection of the cancer
What axonal neuropathy is associated with myelin ovoids
Wallerian degeneration
What type of axonal neurodegeneration can produce the pseudotumor called traumatic neuroma
Wallerian degeneration
What is the term for non-neoplasticism haphazard whirled proliferation of axonal processes and associated schwann cells that results in painful nodules
Traumatic neuroma
What is a common cause of mononeuritis multiplex
Vasculitis
What are some common causes of neuronopathies
Infections like HSV and toxins like platinum compounds
What level is neuronopathy damage at
Level fo cell body
What do peripheral axonopathies preferentially affect
Distal extremities
What are the majority of Guillain-Barré syndrome preceded by
Flu-like illness
What disorder has the clinical presentation of weakness beginning in distal limbs that rapidly advances to affect proximal muscle function (ascending paralysis)
Gullain-barre syndrome
What is the major characteristic of chronic inflammatory demyelination for polyradiculoneuropathy
Symmetrical mixed sensorimotor polyneuropathy that persists for 2+ months
What distinguishes chronic inflammatory demyelination from polyradiculoneuropathy from guillain-barre
Time course and response to steroids
What inflammatory neuropathy is associated with onion bulbs
Chronic inflammatory demyelination polyradiculoneuropathy
Where is the symmetric polyneuropathy with lepromatous leprosy most severe
In relatively cool distal extremities and in face because lower temperature favors mycobacterial growth
Where does lepromatous leprosy predominate (like what cells)
Pain fibers
What dysfunction is prominent with diptheria
Prominent bulbar and respiratory muscle dysfunction
What is the most common cause of peripheral neuropathy
Diabetes
What dysfunctions of the ANS are common with diabetic neuropathy
Postural hypotension, incomplete emptying of bladder, sexual dysfunction
What is the primary event in uremic neuropathy
Axonal degeneration
What tumors often lead to brachial plexopathy
Neoplasms of lung
What neoplasms often lead to obturator palsy
Pelvic malignant neoplasms
Polyradiculopathy involving LE may develop when the cauda equina is involved by _______
Meningeal carcinomatosis
What is the most common paraneoplastic form of paraneoplastic neuropathies
Sensorimotor neuronopathy
What is sensorimotor neuronopathy most commonly associated with
Small cell lung cancer
What is Charcot-Marie-tooth disease clinical manifested as
Distal muscle atrophy, sensory loss and foot deformities
What are some morphological changes that occur with the demyelination groom forms of Charcot-Marie-tooth disease
Schwann cell hyperplasia and onion bulb formation
What is CMT1A caused by
Duplication of a region of chromosome 17 that includes PMP22 gene
How does CMT1A prevention
In 2nd decade of life as slowly progressive distal demyelinating motor and sensory neuropathy
What is CMT1B caused by
Mutations in myelin protein zero gene
What is CMTX linked to mutations in
GJB1 gene which encodes connexin 32
What type of injury occurs in CMT2
Axonal rather than demyelinating injury
What is CMT2A caused by
Mutation in MFN2 gene (which is required for normal mitochondrial fusion)
What is hereditary neuropathy with pressure palsy caused by
Deletion of gene encoding PMP22
What are tomaculi characteristic of
Hereditary neuropathy with pressure palsy
What gene is involved in familial amyloid polyneuropathies
Transthyretin gene
What is the mutated gene in familial amyloid polyneuropathies prone too
Deposit as amyloid fibrils
What nerve is compressed with saturday night palsy
Radial nerve
How do disorders that impair function of NMJ as a general statement present
With painless weakness
What disorders should be considered with ragged red fibers and parking lot inclusions
Myopathies associated with inborn errors of metabolism
What disease of skeletal muscle is associated with telangiectasias and dropout of capillary vessels
Dermatomyositis
What are the anti Mi2 antibodies involved in dermatomyositis directed against
Helicase implicated in nucleosome remodeling
What are the anti-jo1 antibodies involved in dermatomyositis directed against
Enzyme histidyl t-RNA synthetase
What other things is anti-jo1 antibodies associated with besides dermatomyositis
Interstitial lying disease, nonerosive arthritis, skin rash (mechanics hands)
What cases of dermatomyositis are anti-p155/p140 autoantibodies associated with
Paraneoplastic and juvenile cases
What muscles does dermatomyositis typically affect first
Proximal muscles
What is the name for the characteristic lilac colored discoloration of upper eyelids associated with dermatomyositis
Heliotrope rash
What is the name for the scaling erythematous eruption or dusky red patches over the knuckles, elbows and knees associated with dermatomyositis
Gotten papules
What cells are a prominent part of the inflammatory infiltrate in affected muscles of polymyositis
CD8+ T cells
What characteristics of dermatomyositis is absent in polymyositis
Perifascicular pattern of atrophy
What is the most common inflammatory myopathy in patients 65yo+
Inclusion body myositis
What disease presents as slowly progressive muscle weakness that tends to be more severe in quads and distal upper extremity muscles
Inclusion body myositis
What disease of skeletal muscle is associated with cN1A
Inclusion body myositis
What disease is rimmed vacuoles, tubulofilamentous inclusions and cytoplasmic inclusions associated with
Inclusion body myositis
What are the leading culprit for toxin myopathies
Statins
What gene is involved in central-core disease (autosomal dominant)
Ryanodine receptor 1 (RYR1)
What disease goes along with the pathological finding of cytoplasmic cores represented by demarcated central zones in which the normal arrangement of sarcomeres is disrupted and mitochondria are decreased in number
Central core disease
What disorder should be thought of with nemaline rods
Nemaline myopathy (NEM)
What fibers does nemaline myopathy primarily occur
Type 1 fibers
What is the mean age of death in duchenne MD
25-30 yrs
What chromosome are dystrophin mutations on
X chromosome
What is the first indication of muscle weakness with Muscular dystrophy
Clumsiness and inability to keep up with peers
Where does the weakness begin that is associated with muscular dystrophy
Pelvic girdle muscles and extends to shoulder girdle
What is myotonic dystrophy caused by
Expansion of CTG triplet repeats in 3’ non-coding region of DMPK gene
What muscle dystrophy has characteristic pattern of muscle involvement that includes prominent weakness of facial muscles and muscles of shoulder girdle
Fascioscapulohumeral dystrophy
What is overexpressed with fascioscapulohumeral dystrophy
DUX4 on chromosome 4
What does carnitine palmitoyltransferase II deficiency cause
Episodic muscle damage with exercise and fasting
What does carnitine palmitoyltransferase 2 deficiency impair the transport of
Free fatty acids into mitochondria
What is the glycogen storage disease affecting skeletal muscle that results in episodic muscle damage with exercise
Myophosphorylase deficiency (McArdle disease)
What does acid Maltese deficiency result in
Impaired lysosomal conversion of glycogen to glucose, causing glycogen to accumulate within lysosomes
What clinical features are associated with the mitochondrial myopathy of Kearns-Sayre syndrome
Ophthalmologist, pigmentary degeneration of retina, complete heart block
What does mutations in KCNJ2 cause
Andersen-Twail syndrome
What is Andersen-Twail syndrome associated with (clinical)
Periodic paralysis, heart arrhythmias, and skeletal abnormalities
What are mutations in SCN4A associated with causing
Several auto disorders with presentation ranging from myotonia to period paralysis
What is the most common cause of hypokalemia paralysis
Missense mutations in CACNA1S
What do mutations in CLC1 cause
Myotonia congenita (decrease in myotonia dysotrophy)
What ion channel mutation can lead to malignant hyperthermia
RYR1
What type of channel is KCNJ2
K+ channel
What type of channel is SCN4A
Na+ channel
What does Merlin usually do
Normally restricts cell-surface expression of growth factor receptor
What is the term for dense eosinophilic areas containing spindle cells arranged into cellular intersecting fascicles
Antonio A
What should you think of when you see antoni A and Verocay bodies
Schwannomas
Where do most schwannomas occur
Cerebellopontine angle
What cranial nerve is most often affected by schwannomas
CN VIII
What is the term for benign, neoplasticism schwann cells admired with perineurial-like cells, fibroblasts, mast cells and CD34+ spindle cells
Neurofibromas
How do neurofibromas often present
As pedunculated nodules
What should you associate tactile-like bodies with
Diffuse neurofibromas
What type of neurofibromas are found in deep or superficial locations in associated with nerve roots or large nerves and is uniformly NF1-associated
Plexiform type
What type of neurofibromas should be considered with a shredded carrot appearance of collagen
Plexiform type
What is neurofibromin
Tumor suppressor that inhibits RAS activity but stimulating activity of GTPase
Are most malignant peripheral nerve sheath tumors high or low grade
High grade
What do most malignant peripheral nerve sheath tumors result from
Malignant transformation of plexiform neurofibromas
How do malignant peripheral nerve sheath tumors appear at low power
Appears marbilized due to variations in cellularity
What type of tumor is a triton tumor
Malignant peripheral nerve sheath tumor
What should you think of with Lisch nodules and cafe au lait spots
Type 1 neurofibromatoses
What is the most common tumor with type 1 neurofibromatoses
B/L 8th nerve schwannomas and multiple meningiomas
What chromosome is NF2 gene located on
Chromosome 22
