relating pathophysiology to signs and symptoms bacterial meningitis

Daytonite, BSN, RN · May 8, 2008

first of all and primarily, you need to know the general inflammatory response because it is what occurs whenever there is any invasion by bacteria, virus or some foreign body or substance. that is basic to all body invasions:

https://allnurses.com/forums/f50/histamine-effect-244836.html. when you see "itis" at the end of a medical disease, immediately start thinking about the inflammatory response--period, end of story.

the cardinal signs and symptoms of inflammation are redness, heat, swelling and pain and these are due to the pathophysiology of the inflammatory response. they are because (1) redness due to the dilation of the blood vessels, (2) heat also due to the vasodilation and increased blood flow, (3) edema due to intravascular fluids leaking into the surrounding tissues from the increased permeability of the blood vessels, and (4) pain due to the pain receptors being stimulated by the swollen tissue and ph changes from all these chemicals excreted during the inflammatory response. it is easy to see these symptoms when the inflammation is, let's say, in a boo boo on the surface of the skin--you see the reddened skin, can feel the heat if you touch it, notice the swollen bump and see the draining pus. when it is occurring inside the body in tissues like the meninges you can't "see" these things happening with your own eyes, but take my word for it--it is going on! we have to look for other assessment data as evidence of it.

now, with meningitis, the infection is either introduced directly through a fracture of the sinuses or skin contamination if there is a myelomeningocele. the inflammation response kicks right in.

however, meningitis is often a complication of some other bacterial infection in the body, often in the paranasal sinuses due to sinusitis, the mastoid due to otitis media or even the lungs (pneumonia). how? the blood stream. let's go back to the pathophysiology of the inflammatory response. keep in mind that with any infection inflammation always occurs; it is the general response to any bacterial invasion and it results in vascular permeability. think of vascular permeability as a free ticket and open doors in the cell walls, an invitation, for any bacteria to hop aboard the river blood running nearby and take a ride. if they step off at the meninges, hello bacterial meningitis.

now, you are saying that you are having a hard time relating the signs and symptoms with the pathophysiology of meningitis. this is the list of symptoms that i come up with for bacterial meningitis. if i'm missing one that you found, please post it. every single one of them in some way traces its way back to one of the 4 cardinal signs of inflammation. keep in mind that the brain is encased in the skull and the spinal cord in the spinal canal so that swelling causes serious problems for them because the tissues have no room to expand, so swollen brain and spinal cord cells get crushed, irritated, start to elicit funky manifestations and if the swelling isn't stopped, they will start permanently dying.

headache, often worsens with movement (cardinal sign of inflammation: pain)
fever (cardinal sign of inflammation: heat--invading bacteria cause the body to reset it's thermostat to a higher level)
nausea/vomiting (the effect of the toxic substances spewed into the body by the invading bacteria)
weakness (weakness of the muscles secondary to irritation of the nerve cells that control them)
photophobia [sensitivity to light] (cardinal sign of inflammation: edema--the edema irritates the nerve cells of the optic nerve which produces the visual changes)
confusion, delirium (cardinal sign of inflammation: edema)
seizures (cardinal sign of inflammation: edema--the edema irritates the nerve cells of the brain which produces the seizure)
meningismus [the general term for irritation of the brain and spinal cord]
rigors [sudden chills followed by profuse heat and sweating] (cardinal sign of inflammation: heat--invading bacteria cause the body to reset it's thermostat to a higher level)
profuse sweating (cardinal sign of inflammation: heat--invading bacteria cause the body to reset it's thermostat to a higher level)
kernig's sign [reflex contraction and pain in the hamstring muscles when the leg is flexed and then extended] (a symptom of meningeal tissue irritation due to edema)
brudzinski's sign [neck pain and resistance to flexing the head and neck forward toward the sternum of the chest] (a symptom of meningeal tissue irritation due to edema)
declining level of consciousness (cardinal sign of inflammation: edema)
cranial nerve palsies (cardinal sign of inflammation: edema--the edema irritates the nerve cells of the spinal cord which results in the palsies)
symptoms of increased intracranial pressure (cardinal sign of inflammation: edema)

FunkiMunki · May 8, 2008

thankyou so much for your help much appreciated you are a truely excellent teacher :bow:

rhambie_09 · May 4, 2009

:yeah:excellent!!! this happened to be my case for our case study... thnx for your help... :up:

nerdtonurse?, BSN, RN · May 7, 2009

I will add that one of the signs I always was told to look for *stiff neck* wasn't present in the person I had as a patient with bacterial meningitis -- because the poor thing ALSO had encephalitis from an insect bite. According to our neurologist, when you get a pt with both, you DON'T get stiff neck. All I was told about the pt was that they were "headache/near syncopy" which could have been anything from a migraine to pregnancy to ETOH abuse. It ended up with me getting Cipro....