Explain the mechanism of headache, neck stiffness, photophobia and N&V in meningitis.
- Headache: raised ICP
- Neck stiffness: cervical muscle spasm
- Photophobia: oedema causes over-stimulation of retinal photoreceptors with electric impulses to optic n.
- N&V: afferent nerves to the vomiting centre arise from splanchinic and vagal n., vestulo-labyrithine receptor, cerebral cortex and the chemoreceptors trigger zone (which samples CSF)