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Might be acute inflammatory demyelinating polyradiculopathy (FA 2019 p.512): "Most common subtype of Guillain-Barré syndrome. Autoimmune condition that destroys Schwann cells via inflammation and demyelination of motor fibers, sensory fibers, peripheral nerves..."
sounds really great, and i thought the same and answered the same way.
but while in the exam, i had that "how THE FUCK could motor weakness be an afferent??" moment.
quite frequently forget the fact that this is an nbme full of mess. lol.
It could be explained by the lack of the sensory component for the DTR and not the motor neurons?
I focused on the loss of vibration and joint position sensation. Pacinian corpuscles sense vibration. Meissner corpuscles and Merkel discs sense position. These sensory receptors are all large myelinated afferents
FA 2019 p.482
the question asks the most likely explanation for the SENSORY findings
Can anyone explain numbness and tingling ? Isnt that through unmyelinated fibres?
@aaftabsethi unmyelinated afferents include fibers that carry: slow pain, heat, and olfactory senses.
GBS is an inflammatory demyelinating polyneuropathy affecting motor and sympathetic efferent fibers.
Sensory afferent fibers are also affected.
It presents with acute, ascending bilateral muscle weakness, sensory loss, and Hyporeflexia.
Autoantibodies are against GM1 gangliosides on myelin!
Acute inflammatory demyelinating polyradiculopathy is a subtype of GBS.
submitted by ∗spow(50)
Here's how I thought through this. problem with DCML (absent proprioception and vibration sense), problem with deep tendon reflexes (DRGs), ataxic gait (spinocerebellar pathway), mild weakness (motor neurons). The only thing that all of these pathways have in common is that they all use myelinated afferents.
I don't know if Guillan Barre would actually present like this, but you don't have to know what the illness is to figure the question out.