CNS Infections Flashcards
Classic meningitis triad
Fever
Headache
Neck stiffness
(photophobia …?)
What is encephalomyelitis
Inflammation of the brain and the spinal cord
Diagnosis of viral meningitis
Viral stool culture
Throat swab
CSF PCR
Treatment for herpes simplex encephalitis
Aciclovir (IV high dose !!)
How quickly do you need to diagnose herpes simplex encephalitis?
RAPIDLY within 6 hours !!
Diagnosis of encephalitis:
Lumbar puncture
EEG
MRI
If delay, start pre-emptive treatment with aciclovir!!!!! prevents death
Bacteria most likely to cause meningitis in children?
H. influenza
Bacteria most likely to cause meningitis in ppl aged 10-21
Meningococcal
above 21 = pneumococcal
Listeria, group B strep and E. coli are most likely to cause meningitis in which age group?
Neonates
Bacteria most likely to cause meningitis in immunocompromised?
LISTERIA !!!
Satphylococcus / gram negative rods most likely to cause meningitis in which group of people?
Ppl who have had neurosurgery / open head trauma
WHAT ORGANISM CAUSES MENINGITIS IN PEOPLE WITH CRIBRIFORM FRACTURE ?!
Pneumococcal
Organism causing meningitis in patient with CSF shunt?
Staph epidermidis
Which bacteria causes meningococcal meningitis?
Neisseria meningitidis
-this occurs most often in young children
Where is neisseria meningitidis found?
Throats of healthy carriers
-H. influenza also found in the throat
Step. pneumonia is found in the nose !!!
Which meningitis causing bacteria can be found in leukocytes in the CNS? and what are the symptoms due to?
N. meningitidis
-symptoms are due to endotoxin
Vaccination with purified capsular polysaccharide prevents against which meningitis?
Meningococcal meningitis
N. meningitidis
What does H. influenzae require for growth?
Blood factors
Most common type of H. influenzae in children under 4?
H. influenza type b
What type of vaccine is available against haemophilus influenza?
A coonjugate vaccine against the polysaccharide antigen
Which bacteria is found in the nose?
Strep
Some evidence that this bacteria is related to CNS implants like cochlear implants
Strep
Hospitalized patients, patients with CSF skull fractures, diabetics/ alcoholics and young children are most susceptible to which bacteria meningitis?
Penumococcal!!! (caused by strep. pneumoniae)
This type of meningitis is caused by gram positive bacilli?
Listeria
Bacteria most likely to cause meningitis in malignancy? (a.k.a immunocompromised)
Listeria
Antibiotics for listeria
IV ampicillin/amoxicillin
ceftriaxone no value as intrinsically resistant
GRAM POSITIVE ROD
Listeria (LEARN THIS)
Treatment for tb meningitis?
Rifampicine and isoniazid (add pyrazinamide and ethambutol)
Organism seen in HIV meningitis
Cryptotoccus
this is a FUNGUS !!
Treatment for cryptococcus meningitis?
- IV amphotericin b / flucytosine
- fluconazole
This organism gives an aseptic picture on CSF
Cryptococcal meningitis
Other causes of raised neutrophils and low CSF glucose (i.e. causes which aren’t bacterial meningitis)
- viral meningitis in early phase
- leakage of brain abscess
- chemical-meningitis (contrast)
- Behcet syndrom
- Drug induced (NASIDS etc)
What is aseptic meningitis?
Non-pyogenic meningitis
low WBC, protein minimally elevated, normal glucose
Admission to hospital: what type of swab should you take?
Throat swab and swab from any petechial/purpuric lesions
Antibiotics for meningitis (acute admission)
CEFOTAXIME/ CEFTRIAXONE
add ampicillin/amoxicillin if listeria suspected
Penicillin allergy = chloramphenicol with vancomycin
If listeria suspected and penicillin allergy, co-trimoxazole
WHAT DO YOU GIVE WITH ABX FOR SUSPECTED BACTERIAL MENINGITIS?
STEROIDS !!!!
-before or with first dose
When would you not give steroids in meningitis?
- post-surgical meningitis
- severe immunocompromised
- meningococcal or septic shock
Abx used for contact prophylaxis for meningitis
Rifampicin (over 12)
Ciprofloxacin (not licensed but widely used)
Ceftriaxone
Rifampicin - warn of reduced efficacy of OCP, red coloration of urine, staining of contact lenses
Neisseria meningitidis vaccine:
- which serogroups does it vaccinate against?
- who commonly receives it?
- Serogroups A and C
- Commonly used in travel vaccination