Neuropathology

Question 1

Describe the possible routes of entry into the CNS for infection microorganisms. (6)

Answer 1

Direct spread - middle ear infection, basilar skull fracture.
Blood bourne - sepsis
Iatrogenic - cerebral shunt, surgery, lumbar puncture.

Question 2

Describe the common organisms responsible for meningitis in the various age groups. (9)

Answer 2

Neonates - E. Coli, L. Monocytogenes.
2-5 years - H. Influenzae type B
2-30 - N. Meningitides
30+ - S. Pneumoniae.

Question 3

Describe chronic meningitis. (6)

Answer 3

Non-purulent, slow onset, no photophobia or neck stiffness. Caused by M. Tuberculosis. Causes granulomatous inflammation, fibrosis of meninges, and nerve entrapment (esp cranial nerves).

Question 4

List 5 complications of meningitis.

Answer 4

Death from raised intracranial pressure
Cerebral infarction
Cerebral abscess
Subdural empyema 
Epilepsy

Question 5

Describe encephalitis. (3)

Give 3 organisms that cause it and which area they affect. (6)

Answer 5

Inflammation of the brain matter classically due to a virus. It involves inclusion bodies within neurones.
Temporal lobe - herpes
Spinal cord motor neurones - polio
Brainstem - rabies

Question 6

Describe the pathophysiology of a prion related disease. (4)

Answer 6

The prion protein is a normal functional part of synapses.
The mutated prion protein can appear sporadically, familiarly or following ingestion. The mutated protein interacts with the normal ones causing a post-translational conformational change.
They are extremely unstable structures, soo aggregate, causing neuronal death and holes in grey matter.

Question 7

Give 2 examples of prion disease, and explain why one of them is so dangerous. (4)

Answer 7

Bovine spongiform encephalopathy
Variant Creutzfeldt–Jakob disease
vCJD is so dangerous because it has a prolonged incubation period (15+ years) and because the prisons are not eradicated by traditional sterilisation eg cooking.

Question 8

Describe some tumours of the brain. (6)

Answer 8

Meningioma - benign tumour of the meninges
Astrocytoma - malignancy of the astrocytes commonly in the subarachnoid space.
Neurofibromas
Lymphoma
Metastates - most common.

Question 9

Describe the presentation of cerebral palsy. (7)

Answer 9

A series of movement disorders that often occur during childhood due to reduced blood supply to the brain before, during or after birth.
Can also present as seizures, tremors, poor co-ordination, intellectual, visual or hearing disability.

Question 10

Describe risk factors for cerebral palsy. (7)

Answer 10

Primary gravida
Rubella infection during pregnancy
Being a twin
Smoking during pregnancy
Trauma
Premature baby
Hypertension in the mother leading to pre-eclampsia.

Question 11

Describe treatments of cerebral palsy. (3)

Answer 11

No cure.

Only supportive treatments available, like glasses and hearing aids.

Question 12

Describe the pathophysiology of multiple sclerosis. (5)
Diagnosis. (1)
Treatments. (2)

Answer 12

An autoimmune condition resulting from the demyelination of neurones, causing fatigue, vision problems, muscle spasms and thinking difficulties.
Diagnosed by MRI
No cure for MS, but symptom relief is well managed initially.

Question 13

Describe arterovenous malfomations. (4)

Answer 13

An abnormal connection between arteries and veins bypassing the capillary system. Can occur anywhere, but often in the brain, which can be a cause of haemorrhagic strokes.

Question 14

Describe the symtoms of vCJD. (6)

Answer 14

Memory changes
Behavioural changes
Visual co-ordination issues
Involuntary movements
Blindness
Coma