LISTERIOSIS MENINGITIS
DEFINITION:
Inflammation of the meninges by Listeriosis monocytogenes
characterized by an abnormal number of WBC's in the cerebral spinal
fluid.
EPIDEMIOLOGY:
- incidence: 7.6/100,000 live births
- (3rd most common cause of neonatal meningitis)
- age of onset:
- risk factors:
- exposure to Listeriosis monocytogenes
PATHOGENESIS:
- acquired by vertical transplacental transmission
- may lead to stillbirths, abortions, premature labour or
early onset disease
2. Perinatal
- acquired by aspiration or ingestion at the time of
delivery or by nosocomial spread
2. Childhood
- contaminated cheese, milk, uncooked hot dogs,
under-cooked chicken, raw vegetables, shellfish
- enter the body through the gastrointestinal tract
- listeria found in feces of 1% of normal people, 5% of
slaughterhouse workers, and 25% of symptomatic patients
2. Immunosuppressed Patients
- underlying disease (leukemia, lymphoma, Hodgkins)
- post - transplant, chemotherapy, steriods
- colonized gastrointestinal (GI) tract -> blood ->
meninges
- present with meningitis +/- conjunctivitis, hepatitis,
otitis media, sinusitis, pneumonia, endocarditis,
pericarditis
2. Background
- a gram + rod (intracellular parasite)
- divided into 6 serologic types:
- 90% of human disease due to groups Ia, Ib, and IIIb
- infection characterized by a polymorphonuclear response in
the blood, CSF, and other body tissues
- produces disease in many organs:
- liver, lung, adrenals, kidneys, brain
- may form abscesses, microabscesses, granulomatous
reactions
- may cause necrotizing changes in the kidneys and lung
- may also cause suppurative ependymitis, encephalitis,
choroiditis, and gliosis
- in newborn a spectrum of disease is present:
- proportion of neonatal sepsis or meningitis caused by L.
monocytogenes ranges from 4-18%
- rarely caues meningitis after 5 months of age
CLINICAL FEATURES:
- associated with maternal risk factors for sepsis
- associated with serotyes Ia and Ib
- associated with brown-stained amniotic fluid
- fetal acquisition late in pregnancy -> vertical transmission
- illness presents within the first week of life:
- anorexia
- cyanosis
- emesis
- jaundice
- lethargy
- respiratory distress
2. Signs
- skin
- disseminated erythematous papules
- petechial rashes
- white granulomas on mucous membranes (posterior
pharynx) and skin
- hepatomegaly
3. Complications
- abortion, stillbirth, premature delivery
- myocarditis
- neonatal pneumonia with pulmonary infiltrates
- neonatal septicemia with shock
- high mortality rate
- rarely meningitis
4. Granulomatosis Infantisepticum
- severe fulminant disease
- manifest at birth due to an in utero infection
- characterized by:
- shock with high mortality rate
- disseminated lesions in the liver, kidney, lung,
brain, adrenal glands
- pustular and petechial rash
- hepatomegaly
2. Late Onset
- not usually associated with maternal illness
- associated with serotype IVb
- fetal acquisition at or after delivery (nosocomial
transmission)
- signs and symptoms
- 88% - fever
- 88% - meningeal signs
- 82% - irritability or lethargy
- meningitis
- indolent or fulminant disease associated with septicemia
- presents between 7-28 days (mean 14 days)
3. Older Children
- may have prodrome of headache, fever, malaise
- associated with cerebritis, and brain, brainstem, and
spinal cord abscesses
2. Oculoglandular Syndrome
- keratoconjunctivitis, corneal ulcerations, regional
lymphadenitis
3. Others
- conjunctivitis, endocarditis, localized abscesses,
pneumonia, urethritis, sepsis
INVESTIGATIONS:
- gold standard
- sample blood, CSF, meconium, urine, exudate from an
excised skin papule
- sample vagina, cervix, placenta, lochia
- grown on conventional media within 1-2 days
- produces beta-hemolysis on blood agar
2. Serum
- leukocytosis (>15,000/ul)
3. CSF
- pleocytosis with a preponderance of PMN's (>50%)
- elevated protein with decreased glucose
- positive gram stain in only 25% of cases
MANAGEMENT:
- treatment of choice +/- Gentamicin
- Gentamicin may be synergistic with ampicillin
- treat for at least 2 weeks (3-6wks in immuno-comprimised
patient)
2. Trimethoprim-sulfamethoxazole
- bacteriocidal
- may be used in patients allergic to ampicillin
- 3rd generation cephalosporins are not effective
2. Supportive
3. Prognosis
- 50% mortality rate if infected at or near term but increases
to 100% if listerial pneumonia is noted within 12 hours of birth
- 20-50% mortality rate if disease presents 5-30 days after
birth
- if acquired transplacentally, the fetus is almost always
aborted
- long-term sequelae:
- hydrocephalus
- mental retardation
- paralysis
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