Chap 28 Morphology 3

Question 1

Microscopic examination of Acute Disseminated Encephalomyelitis

Answer 1

• Myelin loss with preservation of axons in white matter

Question 2

What is found in the lesions of the early stage of Acute Disseminated Encephalomyelitis?

Answer 2

• Neutrophils

Question 3

What is found in the lesions of the later stage of Acute Disseminated Encephalomyelitis?

Answer 3

• Mononuclear infiltrates

Question 4

What is the histologic similarities between Acute Necrotizing Encephalomyelitis and Acute Disseminated Encephalomyelitis?

Answer 4

• Perivenular distribution of demyelination throughout CNS

Question 5

What are the histologic differences between Acute Necrotizing Encephalomyelitis and Acute Disseminated Encephalomyelitis?

Answer 5

• Acute Necrotizing damage is more severe
• Acute Necrotizing causes destruction of small blood vessels, disseminated necrosis of white and gray matter
• Acute Nec has fibrin deposition and many neutrophils

Question 6

What is the gross cortical atrophy of the brain involved in AD?

Answer 6

• Widening of cerebral sulci in frontal, parietal, and temporal lobes
• Significant atrophy can cause compensatory ventricular enlargement

Question 7

What structures are the first to atrophy in the early course of AD?

Answer 7

Hippocampus and amygdala

Question 8

What is the major microscopic abnormality seen in AD?

Answer 8

Neuritic (senile) plaques and neurofibrillary tangles

Question 9

What are neuritic plaques?

Answer 9

Collections of dilated neuritic processes around a central amyloid core surrounded by a clear halo

Question 10

What is the dominant component of an amyloid plaque?

Answer 10

Ab peptide derived from APP protein

Question 11

What are diffuse plaques?

Answer 11

Deposition of Ab peptides with the absence of neuritic processes
*Found in early stage of plaque development in AD

Question 12

What are neurofibrillary tangles?

Answer 12

Tau-containing bundles of filaments in the cytoplasm of the neurons that displace or encircle the nucleus

Question 13

What do neurofilbrillary tangles look like?

Answer 13

In pyramid cells- “flame” shapes

In rounder cells- basket weave of fibers

Question 14

T/F Tangles are specific to AD

Answer 14

F- tangles are not specific to AD and can be found in other diseases as well

Question 15

What is cerebral amyloid angiopathy?

Answer 15

An invariable accompaniment of AD

- When vascular amyloid Ab40 is present

Question 16

What is the appearance of the atrophic regions of the cortex in FTLD-tau?

Answer 16

Neuronal loss, gliosis, and presence of tau-containing neurofibrillary tangles

Question 17

What occurs in Pick Disease?

Answer 17

Brain shows pronounced asymmetric atrophy of the frontal and temporal lobes with sparing of the posterior 2/3s of superior temporal gyrus

Question 18

What is the appearance of the gyri in Pick disease?

Answer 18

Wafer-thin gyri: “Knife-edge” appearance

Question 19

Where is neuronal loss most severe in Pick Disease?

Answer 19

Outer three layers of the cortex

Question 20

What is the appearance of the surviving neurons of Pick Disease?

Answer 20

Pick cells- swelling of neurons

Pick bodies- cytoplasmic filamentous inclusions that stain well with silver methods

Question 21

What is the gross appearance of FTLD-TDP?

Answer 21

• Atrophy of frontal and temporal lobes

- Neuronal loss and gliosis

Question 22

What is found in the inclusions in FTLD-TDP?

Answer 22

• TDP-43 is phosphorylated and ubiquitinated

Question 23

Why does pallor of the substantia nigra occur in PD?

Answer 23

Loss of pigmented, catecholaminergic neurons

Question 24

What are Lewy bodies?

Answer 24

• Single of multiple cytoplasmic, eosinophilic inclusions

- Have a dense core surrounded by a pale halo

Question 25

What are the components of Lewy bodies?

Answer 25

Filaments and alpha-synuclein

Question 26

What are Lew neurites?

Answer 26

Dystrophic processes that contain aggregated alpha-synuclein

Question 27

What is found in the affected regions of progressive supranuclear palsy?

Answer 27

Globose fibrillary tangles in the neurons and glia

Question 28

What is the appearance of the affected regions of corticobasal degeneration?

Answer 28

Loss of neurons, gliosis, and "ballooned" neurons

Question 29

What is the most specific pathologic finding for CBD?

Answer 29

Clusters of tau-positive processes around astrocytes and the presence of tau-positive threads in gray and white matter

Question 30

What is the appearance of the substantia nigra in CBD?

Answer 30

Loss of pigmented neurons, neuronal achromasia and tangles

Question 31

Where does atrophy occur in the cerebellar form of multiple system atrophy?

Answer 31

Cerebellar peduncles, pons, medulla

Question 32

Where does atrophy occur in the parkinsonian form of multiple system atrophy?

Answer 32

Substantia nigra and the striatum

Question 33

What is the diagnostic element in multiple system atrophy?

Answer 33

Glia cytoplasmic inclusions that contain alpha-synuclein and ubiquitin

Question 34

What is the appearance of the brain in Huntington Disease?

Answer 34

Brain is small and atrophy of the caudate nucleus and frontal lobe

Question 35

What is seen microscopically with Huntington Disease?

Answer 35

Loss of striatal neurons and changes in the caudate nucleus

Question 36

What structures are spared in the brain of a person with Huntington Disease?

Answer 36

- Diaphorase-positive neurons | - Large cholinesterase-positive neurons

Question 37

What is the appearance of the spinal cord in Friedreich Ataxia?

Answer 37

- Loss of axons and gliosis in posterior columns, the corticospinal tract, and spinocerebellar tracts - Degeneration of neurons in spinal cord, brainstem, cerebellum, and motor cortex

Question 38

What is the appearance of the heart in Friedreich Ataxia?

Answer 38

- Enlarged with pericardial adhesions | - In autopsy, multifocal destruction of myocardial fibers with inflammation and fibrosis

Question 39

Where are the abnormalities usually in Ataxia-Telangiectasia?

Answer 39

Cerebellum

Question 40

What occurs in Ataxia-Telangiectasia?

Answer 40

- Loss of Purkinje and granule cells | - Degeneration of doral columns, spinocerebellar tracts, and anterior horn, and peripheral neuropathy

Question 41

Where are telangiectatic lesions found in Ataxia-Telangiectasia?

Answer 41

- CNS, conjunctiva, and skin of the face neck and arms

Question 42

What are amphicytes and when are they seen?

Answer 42

- Enlargement of the nucleus to 2-5 times normal size | - Seen in ataxia-telangiectasia

Question 43

What structures are hypoplastic in ataxia-telangiectasia?

Answer 43

Lymph nodes, thymus, and gonads

Question 44

What is the appearance of the anterior roots in ALS?

Answer 44

- Thin due to loss of LMN fibers and precentral motor in the cortex is atrophic - Reduced number of anterior-horn neurons associated with reactive gliosis

Question 45

What are Bunina bodies and when are the seen?

Answer 45

- Remnants of autophagic vacuoles

Question 46

What occurs in the LMNs and UMNs in ALS?

Answer 46

LMN loss- skeletal muscles get degraded and show atrophy | UMN loss- degeneration of corticospinal tract causing volume loss and absence of myelinated fibers

Question 47

What is the characteristic appearance of Wernicke encephalopathy?

Answer 47

Foci of hemorrhage and necrosis in mamillary bodies and walls of 3rd and 4th ventricle

Question 48

What is the difference between early lesions and later lesions of Wernicke encephalopathy?

Answer 48

Early lesions- dilated capillaries with prominent endothelial cells Later lesions- macrophages and cystic space with hemosiderin-laden macrophages

Question 49

What lesions predominate in Korsakoff syndrome?

Answer 49

The later lesions of Wernicke encephalopathy (lesions infiltrated with macrophages and cystic space with hemosiderin-laden macrophages)