CNS infections Flashcards
What are the most common viral causes of meningitis?
Enteroviruses, Coxsackie, Echo viruses
What are the most common bacterial causes of meningitis in adults and children?
H. influenza type B, Neisseria meningitidis, S. pneumoniae
What 3 bacteria are most common causes of meningitis in children < 3months?
Group B streptococci
Listeria
E coli
What are the clinical signs of meningitis in adults?
fever, headache, vomitting,
stiff neck, altered mental state (but usually conscious- differs to encephalitis), photophobia, rash, seizures
How do babies present with meningitis
more non-specific: irritable, stop feeding, fever, nausia, bulging fontanelle, altered mental state
What are the characteristics of normal CSF?
Clear appearance
WBCS 2.5mmol/L
Pressure <0.4g/L
NO RBCs, NO bacteria
How is meningitis treated?
3rd gen cephalosporins for adults + penicillin + ? for infants, and steroids (
What fungi and Protozoa can cause meningitis?
Cryptococcus (fungus) and amoeba
Why is CSF often cultured in serum broth?
Resuscitation medium -> rich broth that will support growth of small number of bacteria that may have survived initial empirical treatment
What empirical therapy is used in cases of suspected bacterial meningitis?
Cefotaxime (3rd gen cephalosporin)
Benzyl penicillin
What clinical signs are indicative of N. Meningititis? Meningococcal meningitis?
Fine petechial rash (small bruises)
What are the features of the bacteria N meningititis?
Gram neg diplococci
Why is meningitis caused by strep pneumoniae particularly important to identify?
Increasing resistance to beta lactam a -> may not respond to therapies -> add vancomycin to treatment
Also has highest rates of mortality and sequalae
What are the group B strep? In what group of individuals do they commonly cause meningitis?
Gram pos cocci in chains,Beta haemolytic
Commonly grow in gut and vaginal tract and can be contracted by newborns during birthing
What percentage of women carry group b strep as part of their flora?
25-30% of women
