Meningitis Flashcards
What is the definition of meningitis?
Inflammation of meninges covering brain/spinal cord.
What is the most common cause of meningitis?
Viral, but crucial to treat as bacterial until proven otherwise due to high mortality.
In which age groups is bacterial meningitis most common?
Infants, teenagers, young adults.
What are the causative organisms of bacterial meningitis in neonates (<1 month)?
streptococcus agalactiae (group B strep), escherichia coli, streptococcus pneumoniae, listeria monocytogenes.
What are the causative organisms of bacterial meningitis in children and adults (>3 months)?
neisseria meningitidis, streptococcus pneumoniae, haemophilus influenzae type b (Hib).
What is meningococcal meningitis caused by?
N. meningitidis.
What symptoms are associated with meningococcal sepsis?
Non-blanching rash.
What diseases are included under pneumococcal disease?
pneumonia, meningitis, sepsis.
What characterizes aseptic meningitis in the CSF?
White blood cells, gram -ve stain, no bacterial culture.
What accounts for over half of all cases of meningitis?
Viral infections.
List some viral causative organisms of aseptic meningitis.
enteroviruses (e.g. coxsackievirus), herpes simplex virus, varicella-zoster virus, HIV, influenza, mumps.
What is a rare but life-threatening cause of meningitis?
Fungal infections, particularly caused by Cryptococcus.
What are some risk factors for meningitis?
- young age
- neonatal complications
- asplenia
- immunocompromise
- organ dysfunction
- smoking
- overcrowded living environments
What is the classic triad of symptoms for meningitis?
- fever
- neck stiffness
- altered mental status
What are some early non-specific features of meningitis?
- fever
- headache
- nausea and vomiting
- lethargy
- myalgia
- anorexia
- coryzal symptoms
- diarrhoea
What are some later, specific features of meningitis?
- bulging fontanelle (infants)
- neck stiffness (children >1 year)
- photophobia
- non-blanching rash (petechiae or purpura)
- Kernig’s sign
- Brudzinski’s sign
- mottled skin, cold hands, and feet
- altered mental state
- shock
- neurological symptoms
What is Kernig’s sign?
Pain & resistance on passive knee extension with hips fully flexed.
What is Brudzinski’s sign?
Knees and hips flex on bending head forward.
What is the recommended procedure for lumbar puncture in suspected meningitis?
Within one hour of hospital arrival, pre-antibiotic treatment if possible.
What does CSF analysis show in acute bacterial meningitis?
WBC >100.
What are some contraindications for lumbar puncture?
- raised ICP
- shock
- extensive or spreading purpura
What are the aims of management for meningitis?
- supportive treatment
- treatment of causative organism
- treatment of complications
What urgent treatment should be given for suspected meningococcal sepsis?
IV or IM benzylpenicillin.
What antibiotic treatment is recommended for infants <3 months old with bacterial meningitis?
IV cefotaxime + amoxicillin/ampicillin.
