Meningitis Flashcards
What are the five pathogens that can cause meningitis? aka the types?
Viral Mycobacteria Parasitic Bacteria Fungal
What are the most common causes of bacterial meningitis?
Streptococcus Pneumoniae is the most common cause (reason for PCV 13 vaccine)
Neiseria Meningitidis is another leading cause that affects young adults and teens
Haemophilus Influenzae- decreased since HIB vaccine
Listeria Monocytogenes- found in soft cheeses, hot dogs, luncheon meats. Pregnant women, newborns, and older adults and those with weakened immune systems are at highest risk
What is the most common cause of meningitis?
Viral- usually mild and often clears on its own
What are the two most common causes of bacterial meningitis?
80% causes by S. Pneumoniae and N. Meningitidis
What do patients surviving a gram (-) bacillary meningitis have a risk of developing?
A neurocomplication
What was the cause of the 2012 fungal meningitis outbreak?
Contaminated corticosteroid injections from a compounding pharmacy.
160 cases w/ 49 deaths
What is the pathophysiology for bacterial meningitis?
Mucosal colonization Intravascular survival Meningeal invasion Subarachnoid space invasion Blood brain barrier disruption
What is the clinic presentation for adult bacterial meningitis?
Headache, fever, stiff neck (nuchal rigidity), photophobia
Altered mental status (Glascoma scale <14), obtundation, seizures, vomiting
What is the clinic presentation for infants bacterial meningitis?
Irritability, altered sleep, vomiting, high pitched cry, decreased oral intake
What is the clinic presentation for children bacterial meningitis?
Lethargy, confusion, somnolence
What is the inability to straighten the leg when the hip is flexed to 90 degrees?
The kernig’s sign
What is when flexion of the neck causes hips and knee flexion?
The brudzinski neck sign
What is the differential for the increase in WBC in bacterial meningitis?
Neutrophilic
What is the differential for the increase in WBC in bacterial and viral meningitis?
Lymphocytes
What is the lab test done to diagnose meningitis?
CSF- cerebrospinal fluid
Flows unidirectional down the spinal cord
What does a CSF evaluation involve?
Gram stain and culture
What is the empiric therapy for CSF gram stain (+) for a gram (-) bacilli H influenzae?
ceftaz or cefepime +/- gent
What organisms is using PCR effective as a diagnostic method?
Viruses
Mycobacteria
Fungi
What is the management for bacterial meningitis?
Empiric antibiotics Anti-inflammatory agents Fluids Electrolytes Antipyretics Analgesia
When should empiric therapy be initiated?
Until the pathogen is identified
Within 30 minutes of presentation even if LP is not obtained
When should empiric therapy be stopped?
Continued for 48-72 hours or until dx of meningitis can be ruled out.
Once identity of infecting organism and sensitivities are obtained, tailor therapy to infecting organism.
What is the empiric ABX for a CSF gram stain that is negative for an infant less than 1 month?
Ampicillin + cefotaxime or gentamicin
Increased incidence of LIsteria monocytogenes
What is the empiric ABX for a CSF gram stain that is negative for a 1 month-50 y/o?
Cefataxime or ceftriaxone + vancomycin (+ dexamethasone)
What is the empiric ABX for a CSF gram stain that is negative for a patient >50 y/o or alcoholic-increased incidience of L. monocytogenes?
Ampicillin + Ceftriaxone or Cefotaxime + Vancomycin (+dexamethasone)
What do you add for empiric ABX if you suspect Listeria?
Ampicillin
What is the empiric therapy for CSF gram stain (+) for a gram (+) diplococci strep?
ceftriax or cefotaxime + vanco + dexa
What is the empiric therapy for CSF gram stain (+) for a gram (-) diplococci strep N meningitidis?
cefotax or ceftriax
What is the empiric therapy for CSF gram stain (+) for a gram (+) bacilli or coccobacili?
amp + gent
What is the empiric therapy for CSF gram stain (+) for a gram (-) bacilli H influenzae?
ceftaz or cefepime +/- gent
Dexamethasone
Anti-inflammatory, corticosteroid
Inhibits the production of pro-inflammatory cytokines (TNF, IL-1)
Improves CSF parameters (bacterial meningitis)
Needs to be administered before antibiotics
Concern of increased GI bleeding
Concern of decreased antibiotic penetration
Vancomycin penetration not affected by dexamethasone
What does dexamethasone decreased in pediatric patients (>2 mo. of age)?
Hearing loss
What is dexamethasone beneficial against in adults?
S. Pneumoniae, meningitis, reduced mortality
Dexamethasone- uses in adult patients
Cloudy CSF, bacteria on CSF gram stain, CSF >1000 WBCs
Risk of unfavorable outcome reduced from 25% to 15%
Greatest benefit occurred in patients with a GCS score of 8-11
Mortality in patients with S. pneumoniae related meningitis decreased from 34% to 14%
Patients with meningitis and septic shock could have a worse outcome with dexamethasone use and should be avoided for now
What is the evaluation of a response to tx in meningitis?
Signs and symptoms
Vital signs and cerebral dysfunction Q4H for 72 hours
CSF for re-culture, PCR if not responding
Identification and susceptibility testing usually takes 72 hours
Individualize therapy based on results
Neisseria Meningitidis
Gram-negative diplococci
Children and young adults
Winter and Spring
Immunologic reaction (fever, arthritis, pericarditis)- Consider NSAIDS
Behavioral change, seizures, coma
Up to 50%: DIC (disseminated intravascular coagulation- both bleeding and clotting inappropriately. They have purple spots all over their limbs.), purpuric lesions
Neisseria Meningitidis- treatment
Drug of choice is high dose IV PCN G
Alternatives include cefotaxime, ceftriaxone, chloramphenicol
What is the prophylaxis of contacts?
Recommended for close contacts defined as household contacts, day care members, and anyone directly exposed to the patient’s oral secretions (kissing, mouth-to-mouth resuscitation, endotracheal management)
When should prophylaxis of contacts be administered?
Should be administered ASAP (ideally 24hrs), administration 14 days post-contact is probably not useful
What is the prophylaxis regimen?
Adults: Rifampin
Children 1 month to 12 years: Rifampin
Children < 1 month: Rifampin
Alternatives include IM ceftriaxone (i.e. for pregnancy
Streptococcus pneumoniae (Pneumococus)
Gram-positive cocci in pairs
Most common cause of meningitis in adults
Seen commonly in children
Predisposition with pneumonia, endocarditis, splenectomy, head trauma, alcoholism, sickle cell disease, bone marrow transplant
Who has an increased risk for pneumococal meningitis?
Persons with cochlear implants
What is common among survivors of pneumococcal meningitis?
Neurological Sequelae
Streptococcus pneumoniae (Pneumococus)- treatment
Treat with IV 3rd generation cephalosporin for 10-14 days
Cefotaxime
or
Ceftriaxone
If PCN susceptible may switch to penicillin
Vancomycin if resistant to beta-lactams
Streptococcus pneumoniae (Pneumococus)- prevention
- Vaccinate persons > 65 years old, immunocompromised patients and asplenic patients
- Prevnar® (heptavalent conjugate vaccine- PCR13) at 2, 4, 6, and 12 to 15 months (don’t memorize the vaccine schedule)
- Vaccination and chemoprophylaxis with penicillin reduce the incidence of pneumococcal disease in sickle cell disease
Haemophilus Influenzae
Gram-negative bacilli
Introduction of Hib vaccine has decreased incidence by 76-90%
Sterile, subdural effusions seen frequently
May have morbiliform or petechial rash similar to menigicoccal rash (rare)
Haemophilus Influenzae- treatment
30-40% isolates are now ampicillin resistant
Treatment of chouce is cetriaxone or cefotaxime
What is given as a prophylaxis for H.influenzae?
Rifampin
Who does not benefit from the prophylaxis for H. influenzae?
Individuals fully vaccination (> 2 years of age)
Listeria Monocytogens
Gram-positive bacilli or coccobacilli
Primarily affects neonates, immunocompromised adults, and the elderly
Peaks in summer and early fall
Colonizes GI tract then penetrates gut lumen
Listeria Monocytogens- treatment
DOC is IV ampicillin x 14-21 days, plus an aminoglycoside x 10 days
(PCN may be used in place of ampicillin)
Alternative is TMP/SMX (bactrim)
What are the risk factors for Gram-negative Bacilli?
Cranial trauma, neurosurgery
Immunosuppression
Hospitalization
Elderly Patients
What gram-negative bacilli infections are neonates at risk for developing?
E. Coli and klebsiella pneumoniae
Gram negative bacilli- treatment
Treat with IV ceftazidime (more specific cephalosporin) plus gentamicin x 3 weeks if Pseudomonas aeruginosa
Other organisms treat with 3rd generation cephalosporins x 3 weeks
Meningitis is a serious infection associated with significant?
Morbidity and mortablity
Recognition of the clinical signs and symptoms of meningitis is?
Critical
Empiric antibiotic and adjunctive therapy for meningitis should be?
Initiated promptly
Ceftriaxone or Cefotaxime and Vancomycin should be the initial choice for?
Community-acquired meningitis
Ampicillin should be added to meningitis treatment if what?
Listeria is suspected
Usually in old people, babies, and pregnancy
When is chemoprophylaxis necessary?
Niesseria Meningitidis
and
H. Influenzae
