Histopathology Flashcards
Red Neurons can be a result of
ischemia
hypoglycemia
marked pyknosis
Neuronal loss can lead to degeneration of the neuron distally known as
Wallerian Degeneration
Neuronal atrophy due to loss of afferent injury is known as
Transsynaptic degeneration
Hirano Bodies are an accumulation of
actin filaments
_____ _____ are associated with alzheimers disease as well as post-traumatic dementia from repeated blows to the head
Neurofibrillary tangles (IMPORTANT FOR TESTS)
Lewy bodies found in the substantia nigra are considered to be a diagnostic hallmark of advanced stage _________ disease.
advanced stage of parkinson’s disease
neuronal viral inclusions seen in Rabies known as
Pathognomonic Negri bodies are
cytoplasmic inclusions found in the hippocampal pyramidal cells and cerebellar Purkinje cells.
Rosenthal Fibers and Corpora Amylacea display accumulation of heat shock proteins and ubiquitin. What is the significance of each of these?
Heat shock proteins recycle and restore damaged proteins and remove of denatured proteins
UBQ targets denatured proteins and facilitates binding to proteasomes which then break down the proteins to peptides.
Is lipofuscin pathognomonic for anything?
No, it accumulates with age. It’s just an accumulation of oxidized lipids, phospholipids, metals, organic molecules that accumulate from the digestion of bacteria, foreign materials, dead cells, as a result of oxidative degradation of mitochondria and lysosomal digestion (associated with catecholamine degeneration)
They’re seen in increase in cases with more autophagy. mainly in liver and myocardium
What are ependymal cells and what is their histological appearance?
They line the ventricles and assist with moving CSF
they are ciliated columnar.
What happens if ependymal cels die?
They do not regenerate
You may see ependymal granulations aka skips in the ependymal cells because they don’t repopulate
What is the major site of CSF production
Choroid plexus
highly vascular
What is the only non-metastatic primary carcinoma of the brain
Choroid plexus
What do the microglia do and what are they derived from embryologically?
respond to brain injury with a macrophage-like function derived from the mesoderm.
Microglial cells can be involved in what pathological processes?
Demyelinating plaques of MS
what is a rare tumor that can arise in the Choroid plexus and block movement of the CSF?
Choroid Plexus Papilloma that arise in cerebral ventricles
What is the classic appearance of Meningothelial cells?
Whorls
What cell gives rise to the largest category of brain tumors?
Meningothelial cells can give rise to meningiomas which usually grow at the surface and are dural-based
Go-to nerve to biopsy for peripheral neuropathy
Sural Nerve
no motor component though
Nerve biopsy section options for evidence of segmental demyelination
Paraffin
Plastic (get super thin sections)
Electron Microscopy
Axonal degenerations leads to secondary myelin loss because
there isn’t an axon to myelinate
Acute Inflammatory demyelinating polyradiculoneuropathy
Guillain-Barre Syndrome
Proximal and distal weakness with rapid ascending paralysis; often cranial nerve involvement
What nerves are demyelinated in Guillain-Barre
Peripheral nerves and spinal nerve roots
Chronic Inflammatory Demyelinating Polyradiculoneuropathy
symptoms of Gulliain-Barre over 2 months +
relapsing and remitting
Macrocytic and lymphocytic infiltrates as well as thinly myelinated axons found in
Guillain-Barre and CIDP
Demyelination-remyelination seen in
Lepromatous leprosy
schwann cells infected
Demyelination as well as paresthsias/exotoxin-related weakness seen in
Diphtheria
Varicella-Zoster Virus leads to axonal ______
axonal degeneration
latent virus in the ganglia travels along sensory nerves to skin
Charcot-Marie-Tooth genetics?
PMP22 (peripheral myelin gene)
Large onion bulbs, with distal lower extremity weakness and wasting seen in
Charcot-Marie-Tooth
Types of distal symmetric sensorimotor neuropathy in diabetics
axonal neuropathy
relative loss of small myelinated fibers
thickening of small arterioles
Loss of ____ seen in all schwannomas
NF2
Plexiform Peripheral nerve associated with what genetic thing
NF-1
NF-1 is autosomal dominant and associated with what genes?
17q11.2
NF-1 associated with what distinct clinical findings?
cafe au lait spots
Malignant Peripheral Nerve Sheath tumor can arise de novo but also associated with
neurofibroma
Where can schwannoma been seen?
CN VIII
Schwannoma are S-100 positive or negative?
positive for S-100 expression
67 year-old man with progressive hearing loss, recent falls, and a large cerobellar pontine mass. Histology shows Verocay bodes, Antoni A, Antoni B, and decreased hyalinized vessels that show the tumor has been there a while.
Schwannoma NF-2
22q12
