CSF culture

Question 1

routes of a meningeal infection

Answer 1

Hematogenous spread: entry into the subarachnoid space via the bloodstream, most common route is the meninges

• direct spread from the ear, sinus, or brain abscess ( anaerobes and viridans)
• anatomic defect of CNS due to trauma, surgery, congenital abnormality ( spina bifida), implants(shunt)
• intra-neural travel: hiv, rabies, * less common*

Question 2

meningitis

Answer 2

inflammation of the miningies

• increased wbc in csf,
  
  • fever
  • headache
  • nausea
  • vomiting
  • stiff neck
  • rash
• bacterial is the increase in PMS (acute inflammatory exudates) and bacteria
• aseptic is most common and a viral infections

Question 3

aseptic meningitidis

Answer 3

increase WBC with no bacteria

• most commonly assocaited with viruses ( enterovirus)
• less common are fungi, spirochetes, medications, maligncies
• most are self limiting without therapy

Question 4

bacterial meningitis

Answer 4

• • increased polys, decreased glucose, increased proteins, positive direct smear
• headache, fever, rash, stiff neck, nausea, vomiting, neurological abnormalities, change in mental status
• • respiratory tract is the most common source
• -age and underlying factors may increase risk of infection

Question 5

Predisposing risk of Meningitis

Answer 5

• alcoholism
• splenectomy
• diabetes
• prosthetic devices
• decrease in immunocompetence

Question 6

possible agents of meningitis

Answer 6

Haemophilus influenzae type b

• streptococcus pneumoniae
• Niesseria meningitidis
• strep. agalactiae
• Listeria Monocytogens
• fungal (Crytococcus Neoformans, and immitis)
• Viruses: Entrovirus, herpes, West Nile, Mumps, Varicella
• Parasitic: Free-living amebae, Toxoplasma gondii
• TB rare
• Spirochetes Borellia burgdorheria, syphilis

Question 7

antibiotics used to treat meningitis

Answer 7

Cross only with inflammed meninges:
- Penicillin
- Ampicillin
-Cefurozime
- ceftriaxone
- ceftrazidime
- Vancomycin
-Cefotaxime
Cross Blood Brain Barrier
- Chloramphenicol
- sulfonamides
- SXT
- rifammpin

Question 8

N. Meningitidis

Answer 8

5% of population carry in the oropharynx
- transmitted through respiratory secretions, URT establish then enters blood stream
- DIC
- Rash is a common symptom
causes highest number of laboratory deaths, work in hood

Question 9

S. Agalactiae

Answer 9

GBS

• treat with cephlasporins
• GCP
• narrow B hemolysis
• Cat -, CAMP +

Question 10

Listeria monocytogenes

Answer 10

GPR
- small translucent colony with narrow B hemolysis
- umbrella motility on semisolid media
- Cat +, Esculin +, CAMP +
looks like GBS on plate so be very careful
- early infections of a baby is less than 7 days and they got it from mom
- later is within 2-3 months: family member aquired

Question 11

Fungal agents

Answer 11

insidious onset for a month or longer

• Cryptoneoformans: encapsulated, india ink, urease +, test with cryptococcal antigen
• Cocciodies immitis: most common of fungal meningitis, , inhaled and spread. HIV pts.