Transcript Acute Bacterial Meningitis

Dr. Hani Masaadeh, MD, PhD
Objectives
•
•
•
•
•
Define meningitis
Describe prevalence of meningitis
Explain pathophysiology
Identify clinical manifestations
Know the appropriate antibiotic treatment
per age group
Definition
Meningitis: inflammation of the
leptomeninges (the tissues
surrounding the brain and spinal cord)
• Bacterial meningitis
• Aseptic meningits: infectious or
noninfectious
Viral, Rickettsiae,
Mycoplasma
Fungal, spirochetes: syphilis, Lyme
Protozoa: malaria
Malignancy
Lupus erythematous
Lead or mercury poisoning
RISK FACTORS OF MENINGITIS
Age-Viral meningitis occur in children younger than age 5
Bacterial meningitis most commonly occurs in pre-teens and young adults
Community Setting: this infection spreads quickly in large groups such as college
students living in dormitories, military personnel, and children in childcare
facilities are at high risk
Pregnancy- increased risk of listeriosis, which this bacteria can also cause
meningitis.
Working with animals- dairy farmers, ranchers, or others who work with domestic
animals have an increased risk of listeriosis which can cause meningitis
Weakened immune system-diseases, medications and surgical procedure can
increase the risk of meningitis
Symptoms can be the same for
Viral and Bacterial
•
•
•
•
•
•
Fever and chills
Mental status changes
Nausea and vomiting
Sensitivity to light (photophobia)
Severe headache
Stiff neck
4/8/2017
5
Causes of Meningitis
• Bacteria
– Community-acquired - S. pneumoniae, N.
meningitidis, gp B streptococcus
– Post-op or hospital acquired – MRSA, Ps. Aeruginosa
– In the very young and very old Listeria
monocytogenes
• Viruses
– Enterovirus, coxsackie virus, echovirus, HSV-2, etc
• Fungi
– Coccidioides, cryptococcus
• TB
Clinical description
Meningitis is a disease caused by the
inflammation of the protective membranes
covering the brain and spinal cord known as
the meninges. The inflammation is usually
caused by an infection of the fluid surrounding
the brain and spinal cord. Meningitis is also
referred to as spinal meningitis.
4/8/2017
7
Bacterial Meningitis- Outbreaks
Local Health Departments
1. Investigate cases immediately
2. Report cases to Regional Epidemiologist and
Infectious Disease Epidemiology
3. Determine who is at risk by interviewing
physician, family or possibly the case
4. Organize notes and respond as though this
will be an outbreak
5. Send isolates to OLS
4/8/2017
8
So…you get a call from a Hospital
ER at 4:00 on Thursday
A patient has been intubated and the doctor
believes that the symptoms are consistent
with Meningitis
Spinal fluid cultures are incomplete
What should you do first?
4/8/2017
9
Causes of Meningitis
•
-
Bacterial
Haemophilus influenzae
Listeria
Meningococcus
Mumps
Pneumococcus
Group A Streptococcus
Group B Streptococcus
4/8/2017
• Viral
- Arboviral (mosquitoborne) diseases
- Influenza
- LaCrosse Encephalitis
virus
- West Nile Virus
- Also enteroviral
10
Bacterial Meningitis
What types are important in Public Health
Response?
1. Neisseria meningitidis (also called
meningococcal meningitis)
2. Haemophilus influenzae Serotype b (Hib)
Why are they important?
4/8/2017
11
Viral Meningitis
Clinical description: A syndrome characterized by
acute onset of meningeal symptoms- fever, and
cerebrospinal fluid pleocytosis (white cells in the
spinal fluid) with bacteriologically sterile cultures.
Confirmed: a clinically compatible illness diagnosed as
aseptic meningitis,
with no laboratory evidence of bacterial or fungal
meningitis
4/8/2017
12
Age Group
Causes
Newborns
Group B Streptococcus,
Escherichia coli, Listeria
monocytogenes
Streptococcus pneumoniae,
Neisseria meningitidis,
Haemophilus influenzae type b
Neisseria meningitidis,
Streptococcus pneumoniae
Streptococcus pneumoniae,
Neisseria meningitidis, Listeria
monocytogenes
Infants and Children
Adolescents and Young Adults
Older Adults
Streptococcus pneumoniae
One of the top contributors ear
infections and can
cause Pneumococcal pneumonia.
Normally causes
Listeriosis
Listeria monocytogenes
How is Bacterial Meningitis diagnosed?
Early diagnosis is very important
If symptoms occur, patient should
seek medical help immediately
Diagnosis is made by retrieving
growing bacterial from a sample
of the spinal fluid
By performing a spinal tap, spinal
fluid is obtained through a needle
The needle is inserted in the
lower back where the fluid in the
spinal canal can be retrieved.
Other Testing Procedures
Other Cultures- testing of
samples of blood, urine,
mucous, and/or pus from
skin infections
MRI Scan- test that uses
magnetic waves to take
pictures of structures of
inside of body (to clarify
that inflammation is not
some other cause such as a
tumor
CT Scan- a type of x-ray
that uses a computer to
make pictures of
structures inside the
body.
Neisseria meningitidis
Clincal Presentation
• Acute meningitis
– Abrupt or rapid onset
– “flu-like” prodrome – myalgias
– Fever
– Headache
– Nucal stiffness
– Altered sensorium (meningo-encephalitis)
– Rash
Clinical Presentation
• Chronic meningitis
– Insidious, gradual onset
– Weeks of headache
– Low grade fever
– Sweats, chills
– Weight loss
This inflammation puts pressure on the
brain.
Sudden onset of Headaches, neck
stiffness, fear, confusion, vomiting,
irritability, skin rashes, inability to
tolerate light or loud noises
These bacteria can be spread through
nose and throat body fluids.
The body cannot handle this disease on
its own. Untreated bacterial meningitis
has a mortality rate of 50%.
Blood cultures are used to determine
signs of inflammation and a lumbar
puncture is used to definitively test for
the presence of bacteria in the CSF
The bacteria cultures are grown an are
tested with gram staining.
Rashes
Lab
• CT head – r/o cerebritis, brain abscess, brain
edema
• Lumbar puncture
– Pleocytosis
– High protein
– Low glucose (CSF:serum glucose < 50%)
– Bacterial antigens – more sensitive in children
– Gram stain and culture
Prevention
• Vaccines
– Pneumovax
– Meningicoccal vaccine
– Both should be administered to any asplenic patient
• Exposure to meningococcus
– Rifampin 600 mg PO BID x 4 doses
– Only for intimate contacts: spouse,
boyfriend/girlfriend, household contacts
Differential Dx









Viral - 40 % of meningitis
Fungal
Tuberculous
Spirochete
Chemical / Drug induced
Collagen Vascular Disease
Parameningeal infection: brain abscess, epidural
abscess
Subarachnoid hemorrhage
Neuroleptic Malignant Syndrome
LABORATORY FEATURES
• Most often the WBC count is elevated with a shift
toward immature forms
• Platelets may be reduced if disseminated
intravascular coagulation is present or in the face of
meningococcal bacteremia
• Blood cultures are often positive, and can be very
useful in the event that CSF cannot be obtained
before the administration of antimicrobials
– At least one-half of patients with bacterial meningitis have
positive blood cultures
DX
Color
RBC
WBC
Gluc
Prot
Smear
Cx
Normal
Opening
Pressure
Normal
or
elevated
Viral
0
45-85
Normal
or
elevated
Neg
Neg
Funga
l
Normal
or
cloudy
Normal
or
elevated
0
< 45
> 50
Fungal
smear
positive
+/-
TB
Normal
or
cloudy
Elevated
0
1001000
mostly
mono’s
1001000
mostly
mono’s
1001000
mostly
mono’s
< 45
> 50
AFB
positive
+/-
Complications of Meningitis
One of the most common
problems resulting from
meningitis is hearing loss.
Anyone who has had meningitis
should take a hearing test.
•
1.
2.
3.
Young children:
Babyish behavior
Forgetting recently learned skills
Reverting to bed-wetting
•
Older people:
1.
2.
3.
4.
5.
6.
7.
Lethargy
Recurring headaches
Difficulty in concentration
Short-term memory loss
Clumsiness
Balance problems
Depression
Serious complications
•
Other serious
complications can
include:
1.
Brain damage
1.
Epilepsy
2.
Changes in eye sight
Choice of agent
• Selected third generation cephalosporins such as
cefotaxime and ceftriaxone, have emerged as the
beta-lactams of choice in the empiric treatment of
meningitis
• These drugs have potent activity against the major
pathogens of bacterial meningitis with the notable
exception of listeria
PRECAUTIONS
Antibiotic - Prophylaxis
Prophylaxis is for
household contacts of
someone with the Hib
Disease
Recommended the entire
household should receive
this to protect them
A 9-month-old Baby in Septic Shock with
Purpuric Neisseria meningitidis Skin Lesions
.
Meningitis
Viral &Fungal
Causes of Meningitis
• Viruses
– Enterovirus, coxsackie virus, echovirus, HSV-2, etc
• Fungi
– Coccidioides, cryptococcus
• TB
Clincal Presentation
• Acute meningitis
– Abrupt or rapid onset
– “flu-like” prodrome – myalgias
– Fever
– Headache
– Nucal stiffness
– Altered sensorium (meningo-encephalitis)
– Rash
Clinical Presentation
• Chronic meningitis
– Insidious, gradual onset
– Weeks of headache
– Low grade fever
– Sweats, chills
– Weight loss
Acute Meningitis
Lab
• CT head – r/o cerebritis, brain abscess, brain
edema
• Lumbar puncture
– Pleocytosis
– High protein
– Low glucose (CSF:serum glucose < 50%)
– Bacterial antigens – more sensitive in children
– Gram stain and culture
Viral Meningitis
• 75% caused by enteroviruses
– Enterovirus
– Coxsackie virus
– Echo virus
• Other viruses
– HSV2 (HSV1 causes encephalitis)
– HIV
– Lymphocytic choriomeningitis virus
– Mumps
– Varicella Zoster
Viral Meningitis
• Cannot distinguish initially from bacterial
meningitis
• Severe HA, photophobia, nucal rigidity, fever
• May be preceded by a few weeks by viral
gastroenteritis
– Ask pt is he/she had the “stomach flu” some time in
the past couple weeks
• Disease is self-limited, resolves after 7 to 10
days without treatment
CSF
• Low numbers of WBCs : 10 to 500
– PMNs predominate early, Monos or Lymphocytes
later
• CSF to serum glucose ratio usually = 50%
• Protein may be high
• Gram stain, culture and bacterial antigens
negative
• Enteroviral PCR positive about 70% of time
Approach to Viral Meningitis
• Treat like bacterial meningitis until the 72 hr
culture comes back negative, or…
• Enteroviral PCR comes back positive
• Consider acyclovir if CSF HSV PCR positive
– HSV meningitis is self-limited
Chronic Meningitis
Causes
•
•
•
•
Cryptococcus
Coccidioides immitis
Mycobacterium tuberculosis
Other fungal – histoplasmasma, blastomyces,
sporotrix
• Other bacteria – brucella, francisella, nocardia,
borellia
• Non-infectious – Wegener’s, sarcoid,
malignanacy
Presentation
•
•
•
•
•
Insidious onset
Low grade fever
Persistant, worsening headache
Photophobia and nucal rigidty usually absent
Symptoms have usually lasted several weeks
by the time diagnosis is made
Diagnosis
• History
– Exposure to bird droppings (crypto)
– Contacts with TB pts
• CSF
– Modest pleocytosis
– Glucose may be normal, but protein usually high
(very high if coccidioma causes CSF obstruction)
Diagnosis
• TB
– CSF AFB smear usually negative
– AFB culture takes 6 weeks
– Positive PPD
– CSF PCR not standardized yet, but may be helpful;
• Cryptococcus
– India ink
– Cryptococcal Ag in CSF
Diagnosis
• Coccidioidomycosis
– Difficult diagnosis to make
– CSF fungal smear and cultures usually negative
– Titers have high false negativity rate even from CSF
– Any pt with history of pulmonary cocci who
develops HA with pleocytosis should be treated for
cocci meningitis
Treatment
• TB
– Treat like pulmonary TB: INH, Rif, Eth, PZA for two months, then
INH, Rif to comlete 12 months
– Steroids – improves mortality, reduces adverse events (infarcts)
• Crytpococcus
– Amphotericin plus flucytosine for 6 weeks followed by
fluconazole to complete 6 months
• High toxicity rate (renal failure, pancytopenia)
– High dose fluconazole (400 to 800 mg QD) if can’t tolerate
ampho + 5FC
– Serial LPs to reduce CSF pressure and assure clearing of
infection
– In AIDS pts – continue Fluconazole until CD4 >100
Treatment
• Coccidioidomycosis
– Intrathecal amphotericin now rarely used
• Chemical arachnoiditis
– High dose fluconazole (800 to 1200 mg QD)
– Serial LPs to assure improvement of infection
– Incurable – symptoms may resolve, but patient can
never stop fluconazole
• Taper down to no lower than 400 to 600 mg QD
Recurrent meningitis
• Mollaret’s meningitis
• Most common cause is HSV2
• Many other poorly defined causes as well
– Leaking arachnoid cyst
– Cryptogenic
• May respond to acyclovir
Conclusion
• Acute meningitis is most commonly caused by
viruses, then bacteria
• Chronic meningitis can be caused by fungi and
TB
• Recurrent meningitis – Malloret’s