Infectious Diseases Flashcards
Meningitis
Acute inflammation of the meningeal tissues of the brain and spinal cord
How is Meningitis spread?
Spread by:
- Droplet
- Contaminated saliva
- Respiratory secretions
*some people are only carriers
Meningitis: Etiology
Infection (lungs or bloodstream) or penetrating wounds
Meningitis: major organisms
Streptococcus pneumoniae
Neisseria meningitidis
Enteroviruses
Meninges layers
OUTER dura mater arachnoid mater (CSF) pia mater INNER
Meningitis is an infection of which layers
Pia mater
Subarachnoid space
Ventricular system
CSF
Meningitis occurs when?
Fall or Winter
-People are inside in close quarters
Meningitis usually follows which infections?
- Otitis
- Sinusitis
- Pneumonia in immunocompromised
What ages does it effect?
Younger (college students)
Older >40
Prisoner
How does it reach the brain?
Inhaled, attaches to NASOPHARANX, into mucus and then blood stream, finally reaching the BBB and passing through
Meningitis Pathogenesis
- Infection of arachnoid mater and CSF
- Inflammatory response and pus secretion
- Increase in CSF production
- Increase in Intracranial pressure (ICP)
Classic Meningitis Triad
- Fever
- Headache
- Stiff neck
Meningitis: S/S
N/V Photophobia Altered mental state -Drowsiness to coma -Seizures
Meningococcus
- skin rash
- petechiae
Meningitis: two tests to see if meninges are irritated
- Positive Kernig sign
- resistance to leg extension at hip (watch video) - Positive Brudzinski sign
- Neck flexion (forward) causes hip/knee flexion
Bacterial Vs Viral Meningitis
Acute Bacterial Meningitis
- Most common
- High fatality rate
- Long term effects (hearing loss, seizures, brain damage)
- Petechial rash
Acute Viral Meningitis
- Milder form
- No long term effects
Bacterial Meningitis: Treatment
Aggressive Antibiotic Therapy
- IV, often multiple drugs
- Ceftriaxone (Rocephin), Vancomycin
- Acyclovir
Steroid Therapy
Prophylaxis: Vaccines
-Available for Meningococcus, pneumococcus, H. influenzae
Encephalitis
Acute inflammation of the brain tissue
Etiology: Viral
- West Nile encephalitis
- Measles, chicken pox, mumps
- Herpes simplex virus 1 (HSV)
Encephalitis: S/S
Signs appear on day 2 or 3
Range from mild changes in mental status to coma
Other symptoms
- Fever
- Headache
- N/V
- Other CNS changes (seizures)
Encephalitis: Pharm
Viral Infection
- Acyclovir (Zovira) for HSV infection
- Reduces mortality
- Does not reduce neurological complications
Seizure disorders
-Antiseizure meds
Brain Abscess
Accumulation of pus within the brain tissue
Brain Abscess: Etiology
- Local or systemic infection
- Most common (ear, tooth, mastoid, or sinus tract)
Brain Abscess: Organisms
Streptococci or Staphylococcus aureus
Brain Abscess: S/S
Similar to those of meningitis and encephalitis
- Headache
- Fever
- N/V
Brain Abscess: Signs of increased ICP
Drowsiness
Confusion
Seizures
Focal symptoms may reflect area of abscess:
-Example) temporal lobe = visual fields
