CNS Infections- Infants Flashcards
1
Q
Meningitis is the most common and serious manifestation of systemic infection due to _________
A
H. influenzae, type b (Hib)
Most predominate etiologic agent of the infant
2
Q
Hib description
A
- Gram-negative,coccobacilli/pleomorphic rod
- Non-motile
- Fastidious growth requirements
3
Q
Virulence factors of Hib
A
- Exopolysaccharide/Capsule (Type b, polyribose phosphate; PRP) is antiphagocytic.
- Lipooligosaccharide (LOS) provokes meningeal inflammation.
- Peptidoglycan + other wall components enhance meningeal inflammation
4
Q
Risk factors
A
Day care attendance, presence of siblings, crowded households, parental smoking, short duration of breast-feeding
Population with high incidence is people with humoral immunodeficiencies (IgA deficiencies, Alaskan natives/Native Americans who are deficient in IgG2, IgG4)
5
Q
Window of infection in vaccinated vs unvaccinated children
A
- Unvaccinated children the window of infection is >6 m-o-age → 6-y-o-age.
- In vaccinated children, if child seroconverts, there is NO window of infection
6
Q
S/S of Meningitis:
A
- insidious onset (important clues for diagnosis, unusual for bacterial meningitis)
- several days of mild illness (upper respiratory tract or ear infection)
- antecedent symptoms of upper respiratory tract infection and an associated or preceding otitis media are common
- followed by deterioration (common signs & symptoms of meningitis)
7
Q
Sequelae of meningitis
A
- 33-50% risk of permanent neurologic damage, comonly hearing loss.
- Septic arthritis
- Purpura fulminans can occur
8
Q
Treatment
A
ceftriaxone + dexamethasone or other corticosteroids
- Dexamethasone or other corticosteroids must be given 15 min before start antibiotic treatment.
- Use of dexamethasone in non-Hib meningitis is controversial except with S. pneumoniae meningitis in persons >17-y-o-age
9
Q
Prevention
A
- Prophylaxis to decrease carriage rate and incidence of disease.
- Prophylaxis with antibiotics
- Hib polysaccharide conjugate vaccine
