Brain infection and injury

Question 1

Meningitis

Answer 1

An inflammation of the membranes (meninges) that surround the brain and spinal cord. (Specifically inner 2 layers called leptomeninges)
Bacterial meningitis - medical emergency, fatal if left untreated.

Question 2

Meningitis Epidemiology

Answer 2

Bacterial: Children under 5 and 15-19year olds
Viral any age

Question 3

Meningitis Patho

Answer 3

Triggers:
- Auto-immune diseases e.g. lupus
- Adverse reaction to medications
- But most commonly infection - commonly due to direct infection e.g. anatomical defect e.g. spina bifida or skull fracture allowing pathogen to reach cerebral spinal fluid where it then multiplies. But may be a hematogenous spread (through the bloodstream)

Fungi causes most commonly causes chronic M
Bacteria and virus cause acute M
Bacterial - pus forms and may create adhesions causing cranial nerve palsies.
Viral - no pus, can be caused by HIV, Herpes simplex

Question 4

Meningitis S&S

Answer 4

Simple triad - 1) Headaches 2) Fever 3) Nuchal rigidity
Photophobia
Nausea/Vomiting

Bacterial - Sudden onset, rigorous high fever, may be rash present
Viral - Usually benign, Lasts 4-10 days

Question 5

Meningitis Investigations

Answer 5

A physical examination to look for symptoms:
Kernigs sign
Bradzinskis sign
Lumbar puncture
PCR/Blood tests to check for bacteria/virus
CT scan to check brain for swelling etc

Question 6

Meningitis Management

Answer 6

Viral - Usually recover completely in 7-10 days without treatment
Antiviral medicine may help

Bacterial - steroids then antibiotics. 1/20 can die, 1/5 have lifelong symptoms