Bacterial Meningitis by liaoqinmei

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									Presented by,
        Afrah Abdul Wahid Ali
        Ashutosh Wanchu
        Lavina Loungani
        Sophie Gorniewicz
        Tahir Yahya
Case Study
 A 3 yr old girl was brought to the emergency room by
  her parents because of fever and loss of appetite for the
  past 24 hrs and difficulty in arousing her for the past 2
  hrs.

 The developmental history had been normal since birth.
  Her childhood immunization were current.

 She attended a day care center and had a history of
  several episodes of presumed viral infections similar to
  those of other children at the center.
Clinical Features

 Temperature was 39.5 C
 Pulse-130/min
 Respirations-24/min
 BP-110/60 mm Hg
Physical Examination
 Physical examination showed a well-developed and well-nourished
  child of normal height and weight who was drowsy.

 When her neck was passively flexed, her legs also flexed (+ve
  Brudzinski sign, suggesting irritation of meninges).

 Ophthalmoscopic examination showed no papilledema, indicating
  that there had been no long-term increase in intracranial pressure.

 The remainder of her physical examination was normal.
Laboratory Findings
 CSF fluid was cloudy. Gram staining showed many
  polymorphonuclear cells with gram negative diplococci
  suggestive of neisseria meningitidis.

 White blood cell count – 25,000/µL ( markedly elevated), with
  88% PMN forms and an absolute PMN count of 22,000/µL
  (markedly elevated), 6% lymphocytes, and 6% monocytes.

 CSF protein was 100 mg/dL (elevated)

 Glucose was 15 mg/dL (low, termed hypoglycorrhachia)

 Cultures of blood and CSF grew serogroup B N.
  MENINGITIDIS
What is meningitis
 Meningitis is a common name for infections (inflammation)
  that take place in the meninges surrounding the brain and
  spinal cord.

 One of the most serious forms of meningitis is
  Meningococcal meningitis. It is caused by Neisseria
  meningitidis.

 An infection with meningococcal bacteria causes a serious,
  potentially fatal infection called meningococcal disease.You
  may have heard it referred to as bacterial meningitis.
  Meningococcal disease can also cause a very serious condition
  called sepsis (blood poisoning).
Types of meningitis
 Aseptic meningitis: caused by viruses (e.g. mumps), SLE, and
  some types of medications.

 Bacterial meningitis: caused by a bacterial infection.
  Numerous microorganisms may cause bacterial meningitis:

        Neiseria meningitidis
        Streptococcus pneumoniae
        Listeria monocytogenes
        Haemophilus influenzae (type B)
        Mycobacterium tuberculosis
        Group B Streptococci
        Escherichia coli
Types of meningitis (cont.)
 Viral meningitis: caused by viruses (enterovirus).

 Tuberculous meningitis: caused by tuberculosis infection
  due to Mycobacterium tuberculosis.

 Cryptococcal meningitis: caused by infection from a yeast
  called Cryptococcus (found in soil and bird droppings). Often
  associated with AIDS.

 Neoplastic meningitis: caused by the spread of solid
  tumors to the brain or spinal cord.

 Syphilitic meningitis: due to infection with the bacterium
  that causes syphilis
Epidemiology
 SOURCE & RESERVOIR:
   Man
   Subclinical infection
   carrier (they carry the bacteria in their nose and throat but
      never become sick)

 MODES OF TRANSMISSION:
     Close contact with a person who is sick with the disease
     Contact with carriers
     Living in close quarters, such as college dormitories
     Being in crowded situations for prolonged periods of time
     Sharing drinking glasses, water bottles, or eating utensils
     Kissing, sharing a cigarette
Epidemiology (cont.)
 INFECTIOUS MATERIAL:
   Nasopharyngeal secretions


 PEOPLE AT RISK:
   Neonates
   Children, teens, and young adults
   Elderly
   People who have a weakened immune system
   AIDS patients are at high risk for Tuberculous meningitis
Etiology
 Bacterial meningitis is due most often to hematogenous spread
  of bacteria to the leptomeninges.

 It can also be seen after head trauma as skull fracture through
  the sinuses.

 Local infections such as mastoiditis may also lead to meningitis.

 Surgery or CNS infection such as cranial epidural abscess may
  lead to meningitis.
Etiology (cont.)
 Neonates: Group B Streptococci, Escheridia coli, Listeria
  monocytogenes

 Infants: Neissera meningitidis, Haemophilus influenzae,
  Streptococcus pneumoniae

 Children: N. meningitidis, S. pneumoniae

 Adults: S. pneumoniae, N. meningitidis, Mycobacteria,
  Cryptococci
Pathogenesis
 Bacteria extend through the wall of blood vessels into the
  subarachnoid space followed more slowly by neutrophils as
  the blood brain barrier breaks down.

 The combination of bacteria and neutrophils in the
  subarachnoid space irritates the underlying cerebral cortex
  causing edema and increased intracranial pressure.

 If the meningitis is not treated neutrophils are followed by
  lymphocytes and macrophages which with the bacteria, cause
  irritation and degeneration of cranial nerves, production of
  intimal fibrosis in arteries and fibrosis of the leptomeninges
  which can lead to cortical infarcts and blockage of the
  foramina of Lushcka and Magendie with hydrocephalus.
Pathogenesis
General Gross Description
 The brain in purulent meningitis has an opacity of the
  leptomeninges by neutophils and bacteria. This is seen
  over the convexity and the base.

 The brain is also usually swollen.
General Microscopic
Description
 In acute purulent meningitis, the subarachnoid space is filled
  with neutrophils and bacteria with increasing numbers of
  macrophages and lymphocytes over time.

 The underlying brain is usually protected by the pia so that
  there is no intracerebral inflammation, however, the cortex
  and white matter will show spongy change or vacuolization
  due to edema.

 Infants more often show bacteria and neutrophils invading the
  underlying parenchyma.
Symptoms
 Sudden high fever :
    The infection causes a high fever of about 130F or more which does
    not get lower with a tepid bath or fever reducing medicine
   Severe, persistent headache
   Neck stiffness and pain that makes it difficult to touch your chin to
    your chest is due to the swelling around the Meninges
   Nausea and vomiting, sometimes along with diarrhea
   Confusion and disorientation (acting "goofy") can progress to stupor,
    coma, and death
   Drowsiness or sluggishness
   Eye pain or sensitivity to bright light
   Muscle or joint pain or weakness
Symptoms
 Abnormal skin color
 Reddish or brownish skin rash or purple spots that do not turn
  white when u press on them are a sign of sepsis. These may develop
  because of inflammation and bleeding in small blood vessels
  throughout the body, including those under the skin.
 Ice-cold hands and feet
 Numbness and tingling: Sepsis (also called blood poisoning) can
  reduce the amount of blood that gets to the persons hand and feet,
  causing coldness and numbness.
 Seizures: Swelling of brain tissue, increases pressure inside the skull,
  and hampers blood flow, causing stroke symptoms, paralysis and
  seizures.
Glass Test
 Press the side of the glass
  tumbler against the rash
 If the rash does not disappear
  then it is a symptom of
  meningitis.
Symptoms In Children
 Severe high fever
 Feeding problems
 Vomiting
 Irritability
 Seizures
 High-pitched crying
 Decreased appetite
 The skin over the fontanelles (soft spots between the
  skull bones) becomes taut, and the fontanelles may bulge.
 Infants may not develop a stiff neck
Diagnosis
WHEN TO CALL THE DOCTOR:

 If a child 2 years old or younger has an unexplained fever and
  the parent senses that the child is ill.

 If a child becomes increasingly irritable or unusually sleepy,
  refuses to eat, vomits, has seizures, or develops a stiff neck.

 If an adult has fever, headache, skin rash, confusion,
  unresponsiveness (stupor), seizures, and a stiff neck.
Diagnosis (cont.)
KERNIG SIGN:
 The Kernig sign is positive if pain in the lower back or
  posterior thigh occurs when the knee is extended while the
  patient is lying in the supine position and the hip is flexed at a
  right angle.
Diagnosis (cont.)
BRUDZINSKI SIGN:
 The Brudzinski sign is positive if knee and hip flexion occurs
  when the neck is flexed while the patient is in the supine
  position.
Diagnosis (cont.)
NECK STIFFNESS:
 Nuchal rigidity is typically assessed with the patient lying
  supine, and both hips and knees flexed.

INVESTIGATIONS DONE:
 Blood test
 Chest X-ray
 CSF analysis
 CT scan or MRI (MRI preferred over CT due to its
  superiority in demonstrating areas of cerebral edema, ischemia,
  and meningeal inflammation)
 Cultures of samples of CSF, blood, urine, mucus from the nose
  and throat, and pus from skin infections.
Diagnosis – CT Scan
Diagnosis (cont.)
CSF ANALYSIS:
 A spinal tap (lumbar puncture) is performed. A thin needle is
  inserted between L4/L5 to withdraw a sample of CSF.

 The sample of CSF is sent to a laboratory, where the bacteria
  can be cultured and identified.

 3 tubes of CSF are collected
    One for chemistry analysis for glucose & protein levels and
     cell count
    One for microbiology analysis for Gram stain, bacterial
     culture…
    One for cytology analysis

 It will help doctors distinguish between the different type of
  meningitis.
   CONDITION           GLUCOSE   PROTEIN       CELLS


Bacterial meningitis     Low       High         High
                                             (>300/mm³)

  Viral meningitis     Normal    Normal or   Mononuclear
                                   high      (<300/ mm³)

   Tuberculous           Low       High      Pleocytosis
    meningitis                               (300/ mm³)

 Fungal meningitis       Low       High      (<300/ mm³)
Diagnosis (cont.)
 Culture media used for bacterial culture of CSF are:
    5% sheep blood agar
    Enriched chocolate agar
    Enrichment broth (eg, thioglycolate)


 Culture plates should be incubated in an atmosphere
  containing 5 to 10% CO2.

 Antimicrobial susceptibility testing should be performed on all
  clinically relevant bacteria isolated from CSF, so that the
  antibiotic therapy that was started immediately can be
  adjusted if necessary.
Diagnosis (cont.)
 METHODS FOR DETECTING BACTERIA IN CSF:
   Gram staining
   Acridine orange stain
     Fluorochrome stain (bacteria appear bright red)
     More sensitive than gram stain

     Reduction in the time of examination of CSF smear

     Requires fluorescence microscope

   Wayson stain
     Simple & sensitive stain for screening CSF smears for
      bacteria
     Bacteria appear dark blue
Diagnosis (cont.)
  Quellung procedure (Quellung capsular reaction)
      Used to confirm presence of S.pneumoniae,
       N.meningitidis, or H.influenzae
      Antisera specific for the capsular polysaccharides of each
       of these 3 bacteria are mixed with separate portions of
       clinical specimens.
      Formation of Ag/Ab complexes on the surfaces of these
       bacteria induces changes in the refractive indices of their
       capsules.
      The capsules appear clear & swollen.
Diagnosis (cont.)
 METHODS FOR DETECTING BACTERIAL ANTIGENS:
   CIE (counterimmunoelectrophoresis)
   COAG (coagglutination)
   LA (latex agglutination)


 OTHER METHODS USED:
   EIA (enzyme immunoassays)
   LAL Assay (limulus amebocyte lysate assay)
   GLC (gas-liquid chromatography)
   PCR (polymerase chain reaction)
Complications
  If the disease is left untreated, the following manifestatations are seen:
 Increased spinal fluid pressure
 Myocarditis: inflammation of the heart
 Hydrocephalus (blockage of spinal fluid in brain)
 Mental retardation
 Deafness :Loss of hearing from infiltration of the 8th nerve
 Brain damage:Spread from the meninges to the brain is called
   meningoencephalitis
 Severe diarrhea and vomiting
 Internal bleeding
 Low blood pressure
 Shock
 Death
Complications
 Waterhouse-Friderichsen syndrome
 Adrenal gland failure due to bleeding into the adrenal
  gland.
 Symptoms include acute adrenal gland insufficiency and
  profound shock. It is deadly if not treated immediately
Treatment
 Because bacterial meningitis is a medical emergency, it's
  important to start the treatment as soon as it is diagnosed or
  even suspected.

 Bacterial meningitis is treated with antibiotics. The doctor will
  start intravenous (IV) antibiotics with a corticosteroid (eg,
  Dexamethasone) to bring down the inflammation before all
  the test results are even known. When the specific bacteria are
  identified, he may decide to change antibiotics or not.

 In addition to antibiotics, it is important to replenish fluids lost
  from fever, loss of appetite, sweating, vomiting and diarrhea.
Treatment (cont.)
 Some patients may need to stay in the hospital, depending on
  the severity of the illness and the treatment needed.

 Complications can require additional treatment.
    Anticonvulsants (eg, Diazepam or Phenytoin) might be given
     for seizures.
    Additional IV fluids in case of shock or low blood pressure.
    Supplemental oxygen or mechanical ventilation if the child
     has difficulty breathing.

 All neonates should have a hearing test following their
  recovery to screen for hearing impairment.
Microorganism        Recommended              Duration of
                        therapy               treatment



 Streptococcus   Penicillin G or Ampicillin     2 weeks
  pneumoniae                 OR
                   Vancomycin + Third-
                 generation cephalosporin
                    (eg, ceftriaxone or
                        cefotaxime)
  Neisseria              Penicillin G           7 days
 meningitidis               OR
                      Third-generation
                     cephalosporin (eg,
                 ceftriaxone or cefotaxime)
 Haemophilus            Third-generation             7 days
  influenzae           cephalosporin (eg,
                   ceftriaxone or cefotaxime)

   Listeria        Ampicillin or Penicillin G        3 weeks
monocytogenes


Escherichia coli        Third-generation        21 days or 2 weeks
                       cephalosporin (eg,
                   ceftriaxone or cefotaxime)

   Group B         Ampicillin or Penicillin G       14-21 days
 streptococci
Prognosis
 If treated immediately, most patients who have acute bacterial
  meningitis recover fully.

 But when diagnosis or treatment is delayed, permanent brain
  damage or death becomes more likely, especially in very young
  children and older people.

 Some patients develop seizures that require lifelong treatment.

 Even with appropriate treatment, about 5-15% patients die
  from bacterial meningitis.

 10-20% of patients who survive bacterial meningitis have brain
  damage, hearing problems, or developmental difficulties
  (especially in children).
Prevention
 Cases of bacterial meningitis should be reported to state
  or local health authorities so that they can follow and
  treat close contacts of patients and recognize outbreaks.

 Overseas travelers should check to see if meningococcal
  vaccine is recommended for their destination. Travelers
  should receive the vaccine at least 1 week before
  departure, if possible.
Prevention (cont.)
Prevention (cont.)
IMMUNIZATION:
 Haemophilus influenzae type b (Hib) vaccine
    Part of the recommended immunization schedule in
     children.
    3 doses given at 2, 4 and 6 months of age, a booster dose is
     given at 12-15 months of age.

 Pneumococcal conjugate vaccine (PCV7)
    Recommended for children under 2-5 years old who are at
     high risk of pneumococcal disease (weak immune system).
    4 doses given at 2, 4, 6 and 12-15 months of age.
Prevention (cont.)
 Pneumococcal polysaccharide vaccine (PPV)
   Recommended for adults >65 and children >2 years who
    have long-term health problems.
   1 dose is given (under some circumstances a 2nd dose may
    be given).

 Meningococcal conjugate vaccine (MCV4)
   Recommended for children from 11 to 18 years who
    haven't yet been vaccinated, who are at high risk of bacterial
    meningitis, for microbiologists, for overseas travelers.
   1 dose is given.
Prevention (cont.)
CHEMOPROPHYLAXIS:
 Rifampin is given to family members of an infected person to
  reduce their risk of contracting the disease as H influenzae can
  persist in the nasopharyngeal secretions even after a successful
  treatment.

 Pregnant women should not take rifampin as it may harm the
  fetus. They should be treated with single doses of ciprofloxacin,
  azithromycin, or ceftriaxone.
Tuberculous meningitis
DEFINITION:

 Infection of the meninges caused by Mycobacterium
  tuberculosis (acid-fast Gram-positive mycobacterium), the
  bacteria that causes tuberculosis.

 It is the most severe form of tuberculosis.


 It is caused by the spread of Mycobacterium tuberculosis to
  the brain, from another site in the body. Infection begins in the
  lungs and may spread to the meninges by a variety of routes.
Tuberculous meningitis (cont.)
EPIDEMIOLOGY:

 In areas with much tuberculosis,
    tuberculous meningitis usually affects young children
    it develops after the primaty tuberculosis infection


 In areas with less tuberculosis,
    tuberculous meningitis tends to strike adults.
    it is due to reactivation of an old focus of tuberculosis that
     had been dormant
Tuberculous meningitis (cont.)

RISK FACTORS:

 history of pulmonary tuberculosis
 excessive alcohol use
 AIDS
 other disorders that compromise the immune system
Tuberculous meningitis (cont.)
SYMTOMS: (usually begin gradually)

   Fever
   Sluggishness
   Loss of appetite
   Severe headache
   Nausea and vomiting
   Stiff neck
   Sensitivity to light (Photophobia)
   Loss of consciousness
Tuberculous meningitis (cont.)
DIAGNOSIS:

 CSF analysis
 Chest radiography
 CT scan or MRI
 Sputum examination
 Sputum culture
 Tuberculin skin testing
Tuberculous meningitis (cont.)
TREATMENT:
 If tuberculous meningitis is seriously suspected, treatment
  should start immediately.

 Start with 2 month intensive course of isoniazid, rifampin,
  pyrazinamide, and ethambutol followed by 4 months of
  isoniazid and rifampin.

 The use of the corticosteroid (eg, dexamethasone) improves
  survival but probably does not prevent severe disability.

 The hydrocephalus (accumulation of CSF in the brain) may
  require placement of a ventriculoperitoneal shunt.
Tuberculous meningitis (cont.)
COMPLICATIONS:
 Brain damage which may cause
    motor paralysis
    seizures
    mental impairment
    abnormal behavior
    Cerebral ischemia ( anterior circulation most commonly)
    Mesencephalic infarction


    Syringomyelia ( disorder in which a cyst or tubular cavity
     forms within spinal cord)
Prognosis of TB meningitis
 Fatal if untreated
 It causes severe neurologic deficits or death in >50%
  of cases
 Long-term follow up is necessary to detect
  recurrences
Tuberculous meningitis (cont.)
PREVENTION:
 BCG vaccine (given at birth)


 PPD (Purified Protein Derivative) Tuberculin test determines if
  someone has developed an immune response to M.
  tuberculosis
    0.1mL injected immediately under the surface of the skin of
     the forearm
    Test should be read between 48 and 72 hours after the
     injection for induration (hardness)
    Classified as positive based on the diameter of the
     induration
Bibliography
   http://www.cdc.gov/ncidod/DBMD/diseaseinfo/meningococcal_g.htm
   http://www.umm.edu/altmed/articles/meningitis-000106.htm#Following%20Up
   http://www.wrongdiagnosis.com/b/bacterial_meningitis/intro.htm
   http://www.immunize.org/searchiac3/searchiac3.asp?zoom_cat=-
    1&zoom_and=1&zoom_per_page=10&zoom_query=bacterial+meningitis
   http://www.clevelandclinic.org/health/health-info/docs/3300/3384.asp?index=11039
   http://www.dhpe.org/infect/Bacmeningitis.html
   http://www.emedicine.com/PED/topic198.htm
   http://www.nlm.nih.gov/medlineplus/ency/article/000680.htm
   http://www.kidshealth.org/parent/infections/lung/meningitis.html
   http://www.meningitisuk.org/about-meningitis/bacterial-meningitis/frequently-asked-
    questions.htm
   http://www.meningitisuk.org/about-meningitis/bacterial-meningitis/frequently-asked-
    questions.htm
   http://www.guideline.gov/summary/summary.aspx?ss=15&doc_id=5946&nbr=00391
    5&string=bacterial+AND+meningitis
THANK YOU

								
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