bacterial meningitis

Introduction

Types

Layers of meninges

Epidemology

Mechanism

Mode of transmission

Signs and symptoms

Diagnosis

Treatment

Prevention

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Condition where the brain and the spinal cord meningesbecome inflamed

Fluid of a person's spinal cord and the fluid that surrounds the brain

Can be further classified as aseptic, septic, or tuberculous.

•Due to virus

•Less severeVIRAL MENINGITIS

•Severe

•Brain demage.Lossof hearing

•Learning disability

BACTERIAL MENINGITIS

5

6

CNS

BRAINSPINAL CORD

MENINGS

8

3 MEMBRANES MENINGES

• fibrous

•Connective tissue

DURA MATTER

•delicate

•Serous membrane

ARACHNOID

•Vascular membranePIA MATTER

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IT CAN BE CAUSED BY THREE

TYPES OF BACTERIA

Haemophilusinluenza type b

Streptococcus pneumoniae

Neisseriameningitidis

EPIDEMOLOGY

. 3 people per 100,000 anually in western world

Meningitis belt 500 cases per 100,000 sub-saharan africa

Meningococcal ,people living

together

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Mechanism

Blood brain barrier

Normally the brain is protected by the blood brain barrier

Thick membrane that filters out impurities from blood

Does not allow entry into the brain.

In some persons with decreased immunity the infection

crosses the blood brain barrier.

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The subarachnoid space

Once bacteria have entered the bloodstream, they enter

the subarachnoid space.

Swelling of the meninges

This leads to activation of the immune system that leads

to swelling of the meninges

To stop the spread of the infection.

This swelling damages the brain and the nervous system.

Cerebrospinal fluid

The organism may also affect the CSF.

This adds to the injury and there is increased pressure on

the brain and on the skull.

This is called raised intracranial pressure.

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The immune response

With the inflammation, the immune system identifies the

bacteria by its cell wall

The immune cells of the brain (astrocytes and microglia),

respond by releasing large amounts of cytokines

are hormone-like mediators that recruit other immune cells. This

stimulates other tissues to participate in an immune response.

The blood-brain barrier becomes more permeable, leading to

"vasogenic" cerebral edema (swelling of the brain due to fluid

leakage from blood vessels)

The blood vessels are also inflamed leading to

cerebral vasculitis which leads to a decreased blood flow another

type of edema, "cytotoxic" edema.

MODE OF TRANSMISSION direct contact

indirect contact

droplets

INCUBATION PERIOD

5-10 days after breaking blood brain barrier, but

lethal in 24 hours and shorter especially in young

pt.

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1. Signs of infection

Fever

Chills

Malaise

2. Signs of increased intracranial pressure

Headache

Vomiting

3. Signs of meningeal irritation

Nuchal rigidity (stiff neck)

Opisthotonos (backward arching

of the body in muscle spasms)

Photophobia (sensitivity to light)

Diplopia (double vision)

Delirium, stupor, coma: indicates

a decreasing level of

consciousness, an agitated state

followed by a progressive decrease

in consciousness, and ultimately a

lack of any response.

Other symptoms may include:

- nausea

-discomfort looking into bright

lights

- Confusion

-sleepiness.

NEW BORN SYMPTOMS

FEVER

HEADACHE

NECK STIFNESS

SEIZERS

Assessment and stabilization

BACTERIA FROM

SAMPLE FLUID

SPINAL TAP

NEEDLE INSERTED

SPINAL CANAL

FLUID ACESSIBLE

BLOOD TEST

• MARKERS

• INFLAMMATION

C-REACTIVE

• PROTEIN

• BLOOD CULTURES

CEREBROSPINAL FLUID

• LUMBAR PUNCTATE

A CBC will indicate acute infection. Bacterial antigen testing

may also be done.

A Gram’s stain will determine the presence of bacteria. A full

culture should be done with sensitivity.

Radiography skull and spine x-rays used to identify sinus

infections, fracture, or osteomyellitis; chest x-rays may be used

to identify respiratory infections, abscesses, lesions, orgranulomas.

CT scan will usually be normal in uncomplicated cases of

meningitis, but can show diffuse enhancement in some types or

show hydrocephalus.

Electroencephalogram may be performed to show slow wave

activity.

Bacteria

penetrate the blood-brain barrier, endotoxin

and inflammatory mediators initiate a CSF

inflammatory response

causing leakage of protein and fluid out of

the cerebral vasculature.

the processes delineated in septicemia

occur in brain blood vessels, causing

cerebral edema and cerebral vascular

thrombosis.

Both the increased pressure and thrombosis

may lead to a reduction in cerebral perfusion, and consequently cerebral infarction

Brain death

12 to 18 month 4th dose

3DOSES OF Hib

6MONTH AGE

VACCINES

Treatment:

ceftriaxone, one of the third-generation

cefalosporin antibiotics recommended for the

initial treatment of bacterial meningitis.

High-flow oxygen should be administered as soon

as possible, along with intravenous fluids if

hypotension or shock are present

Mechanical ventilation may be needed if the level

of consciousness is very low, or if there is evidence

of respiratory failure

Prevention

A quadrivalent vaccine -Meningococcus

vaccines exist against groups A, C, W135 and

Y

Pneumococcal polysaccharide vaccine

Prophylaxis

meningococcal meningitis, prophylactic

treatment of close contacts with antibiotics

(e.g. rifampicin, ciprofloxacin or ceftriaxone)

can reduce their risk of contracting the

condition, but does not protect against future

infections.