Bacterial meningitis

Question 1

List some of the sequelae of acute bacterial meningitis

Answer 1

hearing loss, seizure, cognitive dysfunction

Question 2

More than 80% of the cases of bacterial meningitis are caused by these three organisms:

Answer 2

Strep pneumoniae
Neisseria meningitidis
H influenza type b

Question 3

List common and uncommon signs and symptoms of acute bacterial meningitis

Answer 3

Common: headache, fever, meningisumus, altered sensorium, Kernig’s sign, Brudzinski’s sign

Uncommon papilledema, seizures and vomiting are of intermediate frequency

Question 4

Describe Kernig’s sign

Answer 4

With the patient supine, flex the hip and knee each to about
90 degrees. With the hip immobile, attempt to extend
(straighten) the knee. In meningeal irritation, this attempt
is resisted and causes pain in the hamstrings.

Question 5

Describe Brudzinski’s sign

Answer 5

Place the patient supine and hold the thorax down upon the
bed. Attempt to flex the neck. In meningeal irritation, this
maneuver will cause involuntary flexion of the hips.

Question 6

If possible, lumbar puncture should be obtained prior to initiation of ______

Answer 6

antibiotics

Question 7

List typical findings in CSF for a person with acute bacterial meningitis

Answer 7

elevated opening pressure
high WBCs (neutrophils)
high protein 
low glucose
positive gram stain (70%)
positive culture (70%)
bacterial antigen and PCR may be positive

Question 8

List the three most common causes of meningitis in neonates

Answer 8

Strep agalactiae
E coli
Listeria monocytogenes

Question 9

List the three most common causes of meningitis in children

Answer 9

Streptococcus pnumoniae
Neisseria meningitidis
Haemophilus influenzae type b

Question 10

List the two most common causes of meningitis in adults

Answer 10

Neisseria meningitidis

Strep pneumoniae

Question 11

List the five most common causes of meningitis in the elderly

Answer 11

Strep pneumoniae
Listeria monocytogenes
Neisseria meningitidis
Haemophilus influenza type b
Gram negative rods

Question 12

List some of the supportive therapies commonly used to treat bacterial meningitis

Answer 12

intubation
fluid restriction (fluid resuscitation if the patient is in shock)
mannitol to increase oncotic pressure in the vasculature
corticosteroids prior to antibiotics- decrease inflammation and edema

Question 13

What antibiotics are used to treat bacterial meningitis?

Answer 13

ceftriaxone + vancomycin

ampicillin added in children less than 1 month old

Question 14

What drugs can be used for prophylaxis of close contacts of people with bacterial meningitis?

Answer 14

ciprofloxacin, rifampin or ceftriaxone

Question 15

List features common to S pneumoniae, N meningitidis, and H influenzae

Answer 15

all have human reservoir
all are transmitted by respiratory droplets
all colonize the nasopharynx and can be cleared or carried asymptomatically
all cause similar clinical syndromes- meningitis, infection of lung, middle ear, sinuses, epiglottis
similar pathogenesis- encapsulated so can evade immune system

Question 16

List additional virulence factors of Neisseria meningitidis (in addition to capsular polysaccharide)

Answer 16

IgA1 protease
LPS in the cell wall (gram -)
can activate complement cascade leading to DIC, Waterhouse-Friderichsen syndrome

Question 17

List some characteristics of Listeria monocytogenes

Answer 17

Intracellular organism
tumbling motility
can cross placenta
virulence factor= listeriolysin O

causes neonatal sepsis (acquired in utero), meningitis (acquired during birth)