CNS Infections Flashcards
What are the most common causes of meningitis?
BACTERIA Neisseria meningitis Streptococcus pneumoniae Staph aures Strep group B Listeria monocytogenes Gram negative bacilli - Echerichia coli MTB Treponema pallidum
VIRAL Enteroviruses ECHO, coxsackie Poliomyelitis Mumps Herpes simplex HIV Epstein Barr
FUNGI Cryptococcus neoformans Candida Albicans Coccidiodes immitis Histoplasma capsulatum Blastomyces dermatitidis
What are the non infective causes of meningitis?
Malignant meningitis
Intrathecal drugs
Blood following SAH
What are the differences between bacterial and viral meningitis?
Bacterial - pus in pia arachnoid, polymorphs, adhesions, cranial nerve palsies, hydrocephalus
Invariably cerebral oedema.
Viral - no pus, predominantly lymphocytic, no adhesions, little or no oedema unless encephalitis occurrs
What is called the meningitic syndrome?
The triad- Headache
Neck stiffness
Fever
Additional- photophobia, vomiting
What is the time of onset of bacterial meningitis
Within hours or minutes
Develops intense malaise, fever, rigors, severe headache, photophobia, vomiting
Can be indolent with a deceptively mild onset
When does the Kernig’s sign and neck stiffness appear?
Appear within hours of onset of symptoms
What is the characteristic feature of uncomplicated meningitis
Pt remains concious
What do you suspect if pt becomes drowsy, lateralizing signs and cranial nerve lesions?
Complications- Venous sinus thrombosis,
Severe cerebral oedema, hydrocephalus
Alternative Dx - cerebral abscess, encephalitis
If a pt presents with a petechial rash and meningitic symptoms
Meningococcal infection
Meningitis sy. + skull fracture/ ear disease + congenital CNS infection such as spina bifida occulta?
Most suspicious organism
Pneumococcal
Rash + pleuritic pain+ meningitic sy
Enterovirus
Immunocompromised pts?
HIV with opportunistic infection
International travel?
Malaria
Occupational - work in drains, canals, polluted water, recreational swimming
And myalgia, conjuctivitis and jaundice
Leptospirosis
What are the types where acute septic shock is seen?
Any bacterial infection
Mostly meningococcal
