11 Aids And The Nervous System - Hirschfeld

Front 1

1. In what year was AIDS first given a clinical description?

2. In what year was it recognized that T-lymphocytes with CD4+ markers are the principle target of the virus?

Back 1

1. 1981 - originally called GIRD (Gay-related immune deficiency)

2. 1983

Front 2

1. HIV-dementia is seen in what % of HIV patients?

2. What % of people that get HIV as children eventually develop encephalopathy?

Back 2

1. 7-10%

2. 23%

Front 3

What are the 3 main neurological complications of HIV infection?

Back 3

1) Toxoplasmosis (most common)
2) Primary CNS lymphoma (most impt for surgeons)
3) Progressive multifocal leukoencephalopathy (PML) --> leads to opportunistic infections

Front 4

What are the most common mass lesions or focal mass lesions seen in AIDS patients?

Back 4

primary lymphomas of the brain

Front 5

Describe primary infection of the brain with HIV

Back 5

*highly neurotropic
*primarily affects microglia and macrophages
*NOT A TERMINAL EVENT
--> infection is caused by lymphocytesbrought in by opportunistic infections

Front 6

When does primary infection of the brain with HIV occur?

Back 6

it occurs early, in the long, asymptomatic phase of HIV

Front 7

What does that HIV virus have that is recognized by macrophages?

Back 7

glycoproteins, specifically GP120, on the viral envelope

Front 8

Describe the two ways HIV can infect human cells

Back 8

1) being absorbed into the macrophage
2) GP120 can break off and stimulate the macrophage to produce neurotoxins
-->Ca2+ in the neuron is released
-->infected macrophages stimulate astrocytes to release NO
-->macrophages also release arachidonic acid which inhibits reuptake of Glu
**Result: NO and Glu neurotoxicity

Front 9

What 4 conditions has AIDS been directly involved in?

Back 9

1) AIDS-dementia comlex (ACD)
2) Distal Symmetrical Polyneuropathy (DSPN)
3) Mononeuritis multiplex
4) Vacuolar Myelopathy

Front 10

What 3 autoimmine disorders are common in dysregulated immune systems?

Back 10

1) Guillain-Bare Syndrome
2) Inflammatory Demyelinating Polyneuropathy (IDP)
3) Gliomas

Front 11

How is HIV encenphalopathy characterized?

Back 11

1) diffuse myelin damage (spongy myelopathy), gliosis, neuronal loss, vascular damage, microglial nodules, and lymphocytic infiltrates (from the body trying to clear up the debris)

Front 12

What is the hallmark of HIV encephalitis?

Back 12

multinucleated giant cells

Front 13

What does HIV encephalitis look like on MRI?

Back 13

increased signal within the periventricular white matter (denotes increased water content surrounding lateral ventricles)

Front 14

What type of spinal cord diseases are:
vacuolar myelopathy and necrotizing vasculitis

Back 14

primary

Front 15

What type of spinal cord diseases are:
spinal cord infection, neoplastic involvement, and epidural spinal cord compression from pyogenic or subacute infection

Back 15

secondary

Front 16

What is the early phase of infection in the peripheral nervous system involvement?

Back 16

acute inflammatory demyelinating polyneuropathy (thought to be an autoimmune disease)

Front 17

What is the late phase of infection in the peripheral nervous system involvement?

Back 17

*mononeuritis multiplex
*painful sensory neuropathy with axonal degeneration (feel like your hand is on fire)
--> common among patients with severe immunodeficiency

Front 18

1. What causes cerebral toxoplasmosis and when does it occur in the AIDS progression?

2. It's thought to be a reactivation of a chronic latent infection in over ____%

Back 18

1. Teponemal parasite that forms a cystic mass
--> it occurs early in the disease when CD4+ counts <100

Front 19

What CD4+ count is considered "immunocompromised"?

Back 19

< 200

Front 20

1) What MRI finding is diagnostic of cerebral toxoplasmosis?

2) Is this condition encephalitic?

Back 20

1) multiple, scattered ring-enhancing lesions

2) yes

Front 21

1) What is the pathological hallmark of cerebral toxoplasmosis?

2) what treatment is there for cerebral toxoplasmosis?

Back 21

1) encysted bradyzoites and free tachyzoites

2) Bactrim (trimethoprim), sulfadiazine, or other sulfa drugs
--> pts usually respond well

Front 22

T/F - almost all patients with cerebral toxoplasmosis have anti-toxoplasma immuniglobins?

Back 22

True

Front 23

Describe Primary CNS Lymphoma:
1) when does it affect AIDS patients?
2) How much more common is it in AIDS patients than the general population?

Back 23

1) late in the disease progression or in less severely affected patients without toxoplasmosis

2) 1000-4000x more common in AIDS patients

Front 24

1) What MRI finding is diagnostic of Primary CNS Lymphoma?

2) is Primary CNS Lymphoma encephalitic?

Back 24

1) ring or solid enhancement with a periventricular location

2) less encephalopathy than toxoplasmosis

Front 25

What is the pathology seen in Primary CNS Lymphoma?

Back 25

small cell, lymphocytic cuffing of blood vessels
--> most are B-cell lymphomas

Front 26

1) What CSF findings help for diagnosing?

2) what is the treatment?

Back 26

1) Epstein-Barr Virus

2) radiation therapy, and sometimes chemotherapy (Ommaya reservoir) directly into the skull via a catheter

Front 27

What is the difference in prognosis between cerebral toxoplasmosis and Primary CNS Lymphoma?

Back 27

Primary CNS Lymphoma is usually fatal, whereas cerebral toxoplasmosis can be successfully treated if caught early enough

Front 28

1) What causes progressive multifocal leukoencephalopathy (PML)?

2) What part of the brain is affected?

Back 28

1) Infection of oligodendrocytes by JC papovavirus (JC virus or JCV)

2) subcortical white matter (cortex not affected; uncommon in cerebellum and spinal cord)

Front 29

What are the MRI findings for PML?

Back 29

scalloped appearance of the subcortical white matter
--> there is NO mass effect
--> brain is non-enhancing on CT or MRI

Front 30

1) What is the pathology of PML?

2) How do you test for PML?

Back 30

1) Bizarre, giant astrocytes, oligodendrocytes with intranuclear inclusions

2) PCR for JC viral DNA

Front 31

1) What is the treatment for PML?

2) What is the prognosis for PML?

Back 31

1) nuceoside analogs or immunomodulation

2) rapid progression to death with the shortest life expectancy and highest mortality rate (3-4 months before death once diagnosed)

Front 32

1) Multiple concurrent pathologies are found in what % of patients?

Back 32

1) 5% - e.g., toxo and PML; CMV and lymphoma

Front 33

What's the most common neurosurgical procedure in AIDS patients?

Back 33

stereotactic brain biopsy

Front 34

What are absolute indications for a brain biopsy?

Back 34

Only need one of the following:
*Failure of anti-toxoplasma therapy after 2-3 weeks
*Non-enhancing lesion(s)
*Solitary enhancing lesion on MRI
*Unable to tolerate anti-toxoplasma therapy
*Impending herniation
*Atypical history making other diagnosis more likely (e.g. systemic lymphoma)
*Seronegative for toxoplasmosis

Front 35

What are relative indications for a brain biopsy?

Back 35

Only need two of the following:
*Large mass effect
*Late in the disease process
*“Eloquent” location
*Absence of encephalopathy
*Presentation while on prophylaxis for pneumocystiscarinii pneumonia
*Deterioration while on anti-toxo medications
*Negative CSF cytology in patients with periventricular lesions