Brain Biopsy Results

[Guest guest]

(The following is my mother's brain biopsy, when she was being tested

for something treatable. )

FINAL DIAGNOSIS:

BRAIN AND LEPTOMENINGES (SPECIMENS B-D):

1. LEWY BODY DISEASE (SEE NOTE)

2. CEREBRAL AMYLOID ANGIOPATHY (SEE NOTE)

3. AMYLOID PLAQUES IN CEREBRAL CORTEX (SEE NOTE)

4. ASTROCYTOSIS (SEE NOTE)

5. ARACHNOIDAL FIBROSIS (SEE NOTE)

DURA MATER (SPECIMEN A): NO DIAGNOSTIC ABNORMALITY RECOGNIZED.

NOTE:

The brain/leptomeningeal specimens contain leptomeninges, cerebral

cortex and underlying white matter. The subarachnoid space is

fibrotic which may be consistent with the patient's age.

The cortex on H & E stain contains rare eosinophilic, rounded

inclusions in the cytoplasm of neurons; on alpha-synuclein staining,

more of these inclusions are apparent, primarily in the deeper

cortical layers. These inclusions are typical of cortical Lewy

bodies. Although the diagnosis of Lewy body disease is made on the

basis of post-mortem examination of numerous regions of the brain,

the presence of numerous Lewy bodies in a small cortical biopsy makes

a diagnosis of Lewy body disease highly likely.

Some leptomeningeal vessels and rare superficial cortical vessels

appear rounded, with thickened walls, and occasional fractured walls.

These vessels stain strongly for beta-amyloid. These findings are

diagnostic of cerebral amyloid angiopathy. Neither vasculitis nor

multinucleated giant cell reaction to amyloid is not noted.

Numerous diffuse amyloid plaques are noted in the cerebral cortex on

beta-amyloid immunohistochemistry, but tau immunohistochemistry is

negative. Amyloid plaques have been noted in cases of dementia with

Lewy bodies. Spongiform change is not observed.

Astrocytosis is highlighted by GFAP immunohistochemistry, and is more

prominent in the white matter. The etiology of the astrocytosis is

not clear, but such gliosis has been reported in the setting of

cerebral amyloid angiopathy.

----

(and this version of the above biopsy allows me to understand what it

means)

NOTE:

The brain/leptomeningeal specimens contain leptomeninges,

[The two innermost layers of tissues that cover the brain and spinal

cord. The two layers are called the arachnoid mater and pia mater],

cerebral cortex,

[A thin mantle of gray matter about the size of a formal dinner

napkin covering the surface of each cerebral hemisphere]

and underlying white matter

[The part of the brain that contains myelinated nerve fibers. The

white matter is white because it is the color of myelin, the

insulation covering the nerve fibers. The white matter is as opposed

to the gray matter (the cortex of the brain which contains nerve cell

bodies).]

The subarachnoid space

[in practice, subarachnoid usually refers to the space between the

arachnoid and the pia mater, the innermost membrane surrounding the

central nervous system]

is fibrotic,

[tissues tend to remain inflamed and become scarred,]

which may be consistent with the patient's age.

The cortex on H & E stain contains rare eosinophilic,

[Eosinophilic is a technical term used by histologists. The context

in which this word is used is in describing the microscopic

appearance of cells and tissues, as seen down the microscope, after a

histological section has been stained with the dye eosin.; Some

structures seen inside cells are described as being eosinophilic, for

example Lewy bodies.],

rounded inclusions in the cytoplasm of neurons; on alpha-synuclein

staining, more of these inclusions are apparent, primarily in the

deeper cortical layers. These inclusions are typical of cortical Lewy

bodies.

[Lewy bodies are abnormal aggregates of protein that develop inside

nerve cells. They are identified under the microscope when histology

is performed on the brain. They appear as spherical masses that

displace other cell components. There are two morphological types:

classical (brain stem) Lewy bodies and cortical Lewy bodies. A

classical Lewy body is an eosinophilic cytoplasmic inclusion that

consists of a dense core surrounded by a halo of 10-nm wide radiating

fibrils, the primary structural component of which is alpha-

synuclein. In contrast, a cortical Lewy body is less well-defined and

lacks the halo. Nonetheless, it is still made up of alpha-synuclein

fibrils.]

Although the diagnosis of Lewy body disease is made on the basis of

post-mortem examination of numerous regions of the brain, the

presence of numerous Lewy bodies in a small cortical biopsy makes a

diagnosis of Lewy body disease highly likely.

Some leptomeningeal vessels and rare superficial cortical vessels

appear rounded, with thickened walls, and occasional fractured walls.

These vessels stain strongly for beta-amyloid.

[beta-amyloid is a small piece of a larger protein called " amyloid

precursor protein " (APP) According to the amyloid hypothesis, these

stages of beta-amyloid aggregation disrupt brain cells by clogging

points of cell-to-cell communication, activating immune cells that

trigger inflammation and devour disabled cells, and, ultimately,

killing cells.]

These findings are diagnostic of cerebral amyloid angiopathy.

[a disease that can cause brain bleeding.]

Neither vasculitis nor multinucleated giant cell reaction to amyloid

is not noted.

Numerous diffuse amyloid plaques

[Classical plaques consist of several microglial cells surrounding a

center core of amyloid that is fibrillized. This kind of plaque is

associated with the presence of degenerating and dystrophic neurites

(axons and dendrites). Diffuse plaques, on the other hand, contain

amyloid deposits with few, if any, amyloid fibrils or abnormal

neurons.]

are noted in the cerebral cortex on beta-amyloid

immunohistochemistry, but tau immunohistochemistry is negative.

[Tau is a protein associated with microtubules in neurons. In

Alzheimer's disease, various other neurodegenerative conditions and

inflammation, tau becomes highly phosphorylated, dissociates from

microtubules, and forms insoluble neurofibrillary tangles. Mutations

of tau have been linked to frontotemporal dementia.]

Amyloid plaques have been noted in cases of dementia with Lewy

bodies. Spongiform change is not observed.

Astrocytosis

[An abnormal increase in the number of astrocytes due to the

destruction of nearby neurons, typically because of hypoglycemia or

oxygen deprivation.]

is highlighted by GFAP immunohistochemistry, and is more prominent in

the white matter. The etiology of the astrocytosis is not clear, but

such gliosis

[A process leading to scars in the central nervous system that

involves the production of a dense fibrous network of neuroglia

(supporting cells) in areas of damage. Gliosis is a prominent feature

of many diseases of the central nervous system, including multiple

sclerosis and stroke. After a stroke, neurons die and disappear with

replacement gliosis.]

has been reported in the setting of cerebral amyloid angiopathy.

[Congophilic angiopathy, also known as cerebral amyloid angiopathy,

is a form of angiopathy in which the same amyloid protein associated

with Alzheimer's disease (Amyloid beta) is deposited in the walls of

the blood vessels of the brain. The term congophilic is used because

the presence of the abnormal amyloid protein can be demonstrated by

microscopic examination of brain tissue after application of a

special stain called Congo red. This deposition of amyloid makes

these blood vessel walls prone to leak blood and can result in brain

hemorrhages (a type of stroke). Because it is the same amyloid

protein that is associated with Alzheimer's dementia such brain

hemorrhages are more common in people who suffer from Alzheimer's,

however they can also occur in those who have no history of dementia.

The hemorrhage within the brain is usually confined to a particular

lobe and this is slightly different compared to brain hemorrhages

which occur as a consequence of high blood pressure (hypertension) -

a more common cause of a hemorrhagic stroke (or cerebral hemorrhage).]