2.2.3 Peripheral Nerve Pathology Flashcards
What are the two main subtypes of neurofibromas?
Cutaneous and Plexiform
What type of neuropathy is associated with diptheria?
Demyelinating; exotoxin-related weakness, parathesias
What gene duplication is associated with CMT1? What gene often affected?
Chromosome 17; PMP22 (peripheral myelin protein 22)
What type of preparation is useful for looking at segmental demyelination?
Teased fiber preparation
What are the two ways in which MPNST can arise?
De Novo or from plexiform neurofibroma
What type of neuropathy is associated with leprosy leprae?
Demyelination-remyelination: schwann cells are infected by m. leprae
Symmetric polyneuropathy
Name this condition
Charcot-Marie-Tooth 1 (CMT1)
From First Aid: It is a group of hereditary nerve disorders related to the defective production of proteins involve in the structure and function of peripheral nerves or the myelin sheath.
What are the classic locations of schwannomas?
Cerebellopontine angle (CPA) w/ CNVIII involvement, Spinal cord, other
What makes a plastic section more beneficial than paraffin sections when looking at nerves?
Plastic sections allow for thinner sections
What is the classical description of this histologic section? What condition?
“Shredded Carrot” appearance; NF-1
Loss of products from which gene is associated with Schwannoma?
NF2 gene products
Identify these areas within the Schwannoma
Left: Antoni A
Right: Antoni B
ID location of tumors in figure A; ID the histo features of figure B
What type of neuropathy is diabetic neuropathy?
Distal symmetric sensorimotor neuropathy (axonal degeneration)
Name condition
CIDP
What is a histological sequele of segmental demyelination?
Onion bulbing: thinly myelinated axon (arrow) surrounded by concentrically arranged Schwann cells, forming an onion bulb
What are these features? and, what dz are they associated with?
Left: Verocay bodies; Right: Hyalinized vessels
Schwannoma
What protein is associated with NF-1? What are the four possible features of NF-1?
Neurofibromin;
Fibromas, lisch nodules, gliomas of optic nerve, and café au lait spots
What mutation can be found in plexiform fibromas
NF-1
Why are physicians hesitant to remove neurofibromas?
To resect the tumor, the physician must take the nerve with it
Name this condition
Guillain-Barré Syndrome or Acute inflammatory demyelinating polyradiculoneuopathy (AIDP)
What are the features of remyelinated sections?
Thin myelin with shorter internodes
If a peripheral nerve biopsy is needed, which peripheral nerve is commonly selected?
The sural nerve (chosen b/c it is purely sensory)
What condition does this histopatholgic section indicate?
MPNST (a sarcoma)
Description: directionality - fascicles, very cellular, large chromatin appearance
Name this condition
Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP)
