Bacterial Meningitis

Question 1

What is the most common bacterial meningitis

Answer 1

Streptococcus pneumonia (since 1995)

use to be H. Influenza

Question 2

What bacterial meningitis agents are vaccines available for?

Answer 2

S. Pneumonia

Nesierria meningitidis

H. Influenza

listeria monocytogenes and Group B step DO NOT have vaccines

Question 3

Why has meningitis cases gone down overall?

Answer 3

Vaccines and universal screening in pregnant patients

Question 4

Epidemiology of meningitis

Answer 4

70% of cases in children under 5 and the elderly

up to 70% case fatality world wide

can cause hearing/blindness if not cured fast enough

Question 5

General diagnosis and treatment

Answer 5

Diagnosis

• LP with CSF analysis
• physcial exam
• blood work and cultures
• neuro imaging

Treatment
- prompt initiation of appropriate empiric therapy (usually steroid such as Dexamethasone and penicillin or broad spectrum antibiotics)

Question 6

Neonatal factors that predispose neonates to meningitis

Answer 6

Immaturity of host defense

Low birth weight

Immaturity of organ systems

Question 7

Maternal factors that predispose neonates to meningitis

Answer 7

Premature ruptures of placenta

GBS (+) infections

Urogential or intrauterine infections during pregnancy

Question 8

Most common signs And symptoms of meningitis in neonates

Answer 8

Temperature fluxes (usually hyperthermia)

CNS manifestations (lethargy, general irritability, seizures, paradoxically irritability(cries when picked up, completely normal when laying alone))

GI disturbances

Respiratory anomalies (dyspnea, apnea cyanosis)

Bulging fontanelle

High pitched crying

TOP 3 agents:

1) GBS
2) Listeria monocytogenes
3) R. Coli

Question 9

If an adult shows GBS infections, what does that usually mean?

Answer 9

Immunodeficiencies

Question 10

Diagnosis of GBS

Answer 10

• B-hemolytic (complete hemolysis)
• always shows CAMP factor
• definitive diagnosis requires isolation from blood and CSF

Question 11

Virulence factors of GBS

Answer 11

Hypervirulent GBS adhesin
- allows for GBS to cross BBB

Capsule

CovR/S
- increases ability to penetrate amniotic membranes

• directly cytotoxic to phagocytes
• Pilins
• allows for invasion of CNS and biofilm production

Question 12

L. Monocytogenes specifics

Answer 12

Gram-positive motile coccus bacillus
- tumbling motility

Grows at all temps

Very high food borne pathogen and can grow on meat and ice creams the most often.

Question 13

Virulence factors of L. Monocytogenes

Answer 13

Listeriolysin O (LLO)
- disrupts phagolysosome and inhibits antigen processing. Also induces apoptosis of phagolysosome 

LPS
- causes inflammation and compliment binding (but doesnt form MAC)

Question 14

2 dangerous manifestation dog Listeriosis

Answer 14

Sepsis and meningitis (especially in immunocompromised and pregnant women)

leading cause of meningitis in cancer and renal transplant patients

Question 15

Classic triad for adult meningitis

Answer 15

Fever

Excruciating headache

Neck stiffness (Brudzinski sign)

Question 16

What is the most common cause of adult meningitis

Answer 16

S. Pneumoniae