CNS Infections- Other agents of neonatal meningitis/encephalitis Flashcards Preview

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Flashcards in CNS Infections- Other agents of neonatal meningitis/encephalitis Deck (17):

E. coli description

-Gram-negative rod
-Enteric bacteria and a coliform
-Oxidase negative
-Encapsulated (exopolysaccharide)
-Capsule provides serum resistance and resistance to killing by neutrophils (aka its antiphagocytic)
-Facultative intracellular pathogen of macrophages and peripheral blood monocytes


Over 200 serotypes of various ______ exist.

All strains of E. coli isolated from extraintestinal infections sites in humans are now designated as _________. These strains are clonal and possess specific virulence factors necessary to cause disease at various non-intestinal sites.

K antigens

extraintestinal pathogenic E. coli (ExPEC)


________ cause the majority of urinary tract infections (UTIs) in humans.

ExPEC strains


The important virulence factor for strains causing meningitis is the __________.

K1 antigen/sialic acid residues

K1 also refers to a specific capsular serotype.


K1 antigen is highly associated with _____________.

severe disease and higher incidence of neurological sequelae


Capsular material is identical to _________. Both capsules are poorly immunogenic in humans due to molecular mimicry.

Neisseria meningitidis group B capsule


Incidence of E. coli in the US is high, causing about 3,500 cases/y of _____________

invasive neonatal disease (sepsis, meningitis, neonatal enterocolitis)


The most common Gram-negative agent of ____________.

-neonatal meningitis in the US
-2nd most common agent of invasive disease in the neonate


Prophylaxis for GBS is causing increasing incidence of ___________

invasive disease by Gram-negative bacteria and especially E. coli K1


There is strong association between vaginal colonization by E. coli K1 and _________

preterm birth
(source of e. coli is mother's colon)


Another agent causing blood/systemic infections in the neonate is

-Klebsiella pneumoniae (encapsulated; K1 or K2 serotypes) causes early and late neonatal sepsis in premature infants, agent is simple to culture and identify.

-Pseudomonas aeruginosa & Klebsiella pneumoniae are found in VLBW infants


A gram positive agent that causes early neonatal sepsis and meningitis is

Staphylococcus epidermidis (CoNS)


6 viruses causing infection and morbidity in neonates

1. Cytomegalovirus (CMV)
2. Herpes simplex virus (HSV 1 & 2)
3. Human herpes virus 6 & 7 (HHV 6 & 7)
4. Non-polio-enterovirus infections (neonatal sepsis/viremia)
5. Human papilloma virus and laryngeal warts
6. Lymphocytic choriomeningitis virus (LCMV)


Mycoplasma spp, Ureaplasma urealyticum, U. parvum and Chlamydia trachomatis are closely associated with ____________.

vertical transmission/during parturition, mother is often asymptomatic, newborn is not


Ureaplasma urealyticum, U. parvum infection of the child occurs via:

1. ingestion of infected amniotic fluid after agent ascends from the vaginal canal.
2. intrauterine bacteremia after crossing the placenta from mother’s blood.
3. **aspiration during passage through birth canal**

These agents produce respiratory infections from perinatal period to 3-y-o-age, esp. in premature infants with chronic lung disease.


How neonate will present if infected with Mycoplasma spp, Ureaplasma urealyticum, U. parvum or Chlamydia trachomatis

1. bronchiolitis
2. respiratory distress (pneumonia, ARDS)
3. cough and wheeze


If neonate is born with eye infections, they may have infection with

1. Neisseria gonorrhoeae
2. Chlamydia trachomatis