Neuron Infectious Diseases (Exam 2) Flashcards
Meningitis: Definition
Acute inflammation of the meningeal tissues of the brain and spinal cord
Meningitis: Comes from?
Infection (lungs or blood stream) or penetrating wounds
What bacteria are the common culprits for meninigitis
Streptococcus pneumoniae
Neisseria meningitidis
What virus is the most common culprit of meningitis
Enteroviruses
What are the meninges?
The three layers that protect the brain and the spinal cord
What are the three layers of the meninges
Pia mater (innermost)
Arachnoid (middle layer)
Dura mater (outermost)
Meningitis is most commonly the infection of
Pia Mater
Subarachnoid space
CSF
Meningitis: Risk Factors
Older Adults
College Students
Prisoners
Military Bases
(large gathering groups)
When does meningitis typically occur?
In the fall or winter people are staying inside with window closed
Follows a sickness because the person might be in an immunocompromised state
How is meningitis spread?
Via respiratory droplet and contact with respiratory tract secretions
Silent spreading of meningitis
People can be asymptomatic and pass the disease on to other without knowing
Meningitis: Pathogeneisis
Bacteria is inhaled and attaches to epithelial cells in the nasopharynx
They then cross the mucosal barrier and enter into the bloodstream
They then travel to the brain and cross the blood brain barrier to infection the meninges
Infection starts in arachnoid mater and CSF
Inflammatory response and pus secretion leads to edema
Increase in CSF production
Increase Intracranial Pressure
Meningitis: Classic Triad
-Throbbing Headache (meningeal irritation)
-Fever (infection)
-Stiff Neck (meningeal irritation)
What action causes pain in person with menegitis?
Trying to touch their chin to their neck
Meningitis: Other Clinical Manifestations
-N/V
-Photophobia (light cause pain)
-Altered mental status (coma/seizures)
-Meningococcus
(Skin rash) (Petechiae)
What causes altered mental status in meningitis?
Increase in intracranial pressure
What are the two test that can be done to check for Meningitis
- Kernig Sign
-Resistance to leg extension and pain causesing flexion of opposite hip - Brudzinski Sign
-Neck flexion causes hip/knee flexion
Brudzinski Sign
Seen in meningitis
Neck flexion causes hip/knee flexion
Kernig Sign
Seen in meningitis
Resistance to leg extension equals pain and causes flexion in other hip
Bacterial Vs Viral Meningitis
Bacterial:
-More common
-Higher fatality rate (within hours)
-Petechial Rash
-Long term effects present
-Septic Emboli (loss of fingers and limbs)
Viral:
-Milder form
-No long term effects
Encephalitis: Definition
Acute inflammation of the BRAIN tissue most commonly caused by virus
Encephalitis: Etiology
Viral Infection
-West Nile (mosquitoes)
-Measles-Chickenpox-Mumps
-HSV-1 (rapid and people can die quick)
Encephalitis: Clinical Manifestations
Signs appear on day 2-3 of infection
Range from mild mental status change to coma
-fever
-headache
-N/V
-Seizures
Brain Abscess: Definition
Accumulation of pus within the brain tissue
