Pathology

Question 1

Specific Symptoms Of Demyelinating

Answer 1

Unexplained optic neuritis

Ophthalmoplegia (MS)

Question 2

Genetic Factors Of MS

Answer 2

Strong association with a DR (2 and 15 in clinical medicine) haplotype of MHC

Associations with IL-2 and IL-7 receptor genes

Question 3

Active Plaques On Microscopy

Answer 3

Centred on small veins

Question 4

CSF In MS

Answer 4

• Elevated protein
• Serum Glucose: Normal
• Lymphocytes
• Macrophages
• Plasma cells
• Increased IgG
• Oligoclonal IgG bands on immunoelectrophoresis

Question 5

Non-demyelinating Ddx Of MS

Answer 5

• Spinal cord neoplasms
• Sarcoidosis
• Infarction of spinal cord
• Vasculitis
• Arteriovenous fistula

Question 6

NOM Antibody + Component

Answer 6

SEARCH THE ANTIBODY

Aquaporin-4

Question 7

Subacute Combined Degeneration Of SC Paraesthesia Direction

Answer 7

Ascending paresthesias

Question 8

Tertiary Syphilis Diagnosis

Answer 8

Clinical exam
History
Serology

Question 9

Hypoxic-ischaemic demyelination areas

Answer 9

Affects globus pallidus and white matter

Question 10

Pathophysiology:
Anti-MAG Neuropathy
POEMS Syndrome

Answer 10

Anti-MAG Neuropathy - Monoclonal IGM Gammopathy

POEMS Syndrome - Plasma Cell Neoplasm

Question 11

Selective Vulnerability

Answer 11

Neurons are the most vulnerable cells in the CNS to ischemia

◦ e.g pyramidal neurons in the hippocampus, and Purkinje cells in the cerebellum.

Question 12

Pick body locations

Answer 12

These are tau-immunopositive bodies predominantly
located in granular neurons in the hippocampal dentate gyrus,
hippocampal CA1 pyramidal neurons, and layer II of frontal and
temporal cortices.

Question 13

IgG Index

Answer 13

• IgG index is derived from the following formula:

IgG In= [IgGCSF/albuminCSF]/ [IgGserum/albuminserum]

Question 14

CNS Tumour Common Types For Age

Answer 14

Adults (70% supratentorial – Intrinsic + extrinsic - 65% primary intrinsic):
Astrocytoma
Glioblastoma (COMMONEST IN BOTH AGE GROUPS)
Meningioma
Metastatic
Oligodendroglioma

Children (Children - 70% infratentorial – Intrinsic - all primary intrinsic):
Astrocytoma (COMMONEST IN CHILDREN - 50%)
Medulloblastoma (45%)

Question 15

Tumours with hydrocephalus in children occur in which cranial fossa usually?

Answer 15

Posterior fossa tumours

Question 16

Diagnosis Of Brain Tumours

Answer 16

MRI!!! Higher and better sensitivity, resolution, and three planar views
MRI with gadolinium contrast is the gold standard
MRI better than CT: Tumor of suprasellar, optic path, infratentorial & pituitary region

Question 17

Lumbar puncture indications in tumours

Answer 17

Indication:
Medulloblastoma
Ependymoma
Germ cell tumours

Contraindications:
Newly dx hydrocephalous sec. to CSF flow obstruction
Tumour causing supratentorial midline shift
Infratentorial tumours

Question 18

What primary brain tumours are highly malignant?

Answer 18

Glioblastoma

Medulloblastoma

Question 19

Factors in the aetiology of CNS neoplasms

Answer 19

1. Sex – gliomas commoner in males
2. Exposure to ionizing radiation implicated in
   immunodeficiency
3. Primary CNS lymphoma – is associated with 4. No convincingevidence has linked CNS neoplasms
   with trauma, occupation, diet, electromagnetic
   fields
   meningiomas commoner in females ~ meningiomas ~ gliomas ~ nerve sheath tumors

Question 20

Tumours are now divided based on whether cells have mutations in which genes?

Answer 20

Tumors are now divided based on whether the cells have mutations in one of the IDH genes (IDH1 or IDH2). For a specific type of tumor, those with IDH mutations tend to have a better outlook.

Question 21

Primitive neuroectodermal tumours/medulloblastoma (not sure which one she meant) molecular subtypes

Answer 21

Wnt pathway activation - gene for β-catenin –good prognosis Hedgehog pathway activation-mutations in PTCH1–intermediate MYC overexpression – poorest prognosis

Wnt and HH lead to personalised therapy

Question 22

How is PCNSL diagnosed?

Answer 22

Stereotactic needle

Question 23

DO LAILA’S SUMMARY ON GENES

Answer 23

At end of the note

Question 24

Distribution of pus in meningitis

Answer 24

Pneumococcal - convexities + near sagittal sinus

H. influenzae - basal (hence the cranial deficiencies)

Question 25

Are fibroblasts part of brain abscesses?

Answer 25

NO we have gliosis

Question 26

Which organism shows a spiderweb appearance when the lumbar tap test tube is left standing?

Answer 26

TB

Question 27

Basilar meningitis causes

Answer 27

H. influenzae TB Histoplasma capsulatum

Question 28

Viral meningitis and encephalitis r/shp

Answer 28

Encephalitis is accompaniedby viral meningitis whereas aseptic meningitis may occur alone. (unrelated to this card but herpes can reach CNS by olfactory)

Question 29

Viral Neurotropism

Answer 29

(1) Neurons – eg. Herpes, polio, rabies, SSPE (2) Astrocytes – eg. Herpes, SSPE (3) Oligodendro glial cells – eg. Papova (JC, SV40) This tropism is influence by : (1) Viral factors (2) Host factor Herpes – HSV1 – temporal lobes Polio – Anterior horn cells of spinal cord Rabies – Ammon’s horn (hippocampus), Purkinje cells

Question 30

HSV Diagnosis

Answer 30

Polymerase chain reaction — Gold standard - Detects HSV DNA in CSF -sensitivity (98 %),specificity (99%) Is positive early in the course of illness. Brain biopsy (not used anymore) — Prior to PCR testing, was only way to diagnose HSVE. Now only role in patients with clinical deterioration despite antiviral therapy or if alternative diagnosis is considered. Examines for HSV by Culture HSV antigens by IHC Viral DNA by in situ hybridization Not done routinely as invasive and can lead to sequelae Viral culture of CSF is rarely positive in the early infection CSF antigen and antibody determinations — not helpful in early diagnosis

Question 31

Triad of congenital toxoplasmosis

Answer 31

Triad of chorioretinitis, hydrocephalus, and intracranial calcifications.

Question 32

Diagnosis of cryptococcus neoformans

Answer 32

Microscopic examination Culture of tissue or body fluids such as blood, CSF, and sputum Cryptococcal antigen test is a rapid test that can be performed on blood and/or on CSF

Question 33

Which stroke has the most rapid onset?

Answer 33

Embolic stroke

Question 34

Where does ICH usually occur?

Answer 34

Cerebellum and basal ganglia

Question 35

Berry aneurysm distribution

Answer 35

1. ACA and ant. comm. artery junction (more on comm.) 2. MCA 3. ICA and post. comm. junction 4. Bifurcation of basilar

Question 36

Lacunar infarct cause

Answer 36

HT + lenticulostriate arteries of BG, internal capsule, putamen, thalamus, pontine tegmentum, cerebellum.

Question 37

Recap salah humood

Answer 37

Week 5