Newman Flashcards
(131 cards)
MC organisms causing acute bacterial meningitis in children of different ages:
1 mo-3 mo:
3 mo-3 yrs:
3 yrs-10 yrs:
10yrs-19yrs:
1 mo-3 mo: GBS
3 mo-3 yrs: S. pneumoniae
3 yrs-10 yrs: S. pneumoniae
10yrs-19yrs: N. meningitidis
What is the difference in acquisition between early-onset (7 days) Group B Strep in neonates?
EARLY-onset GBS reflects vertical transmission from maternal vaginal flora.
LATE-onset GBS suggests community or nosocomial acquisition, although the maternal flora now colonizing the neonate may still be a source of infection.
TQ Mainstay of therapy for tx of MRSA in the pediatric pt:
Vancomycin
classic signs and sx of pediatric bacterial meningitis: (3)
- Fever
- Headache (less likely in younger children)
- Meningeal signs (less likely in younger children)
- Brudzinski and Kernig signs
Signs and sx of pediatric bacterial meningitis in neonates:
- Fever, hypothermia
- Poor feeding, listlessness, hypotonia, pallor, lethargy
- Irritability, shrill cry
- Apnea, seizures
- Jaundice, bulging fontanelle
- Hypoglycemia, intractable metabolic acidosis, shock
Signs and sx of pediatric bacterial meningitis in older infants and children:
Definitive diagnosis is based on:
- Fever, hypothermia (if severely ill)
- Nuchal rigidity, opisthotonos, Kernig sign, Brudzinski sign
- Headache, irritability, lethargy, photophobia, alteration of the sensorium
- Vomiting, nausea, anorexia Definitive diagnosis is based on:
- Bacteria isolated from CSF obtained via lumbar puncture
- Evidence of meningeal irritation demonstrated by increased pleocytosis, elevated protein level, and low glucose level in the CSF
TQ
Bacterial meningitis
- Appearance:
- Pressure:
- WBC count:
- Differential count (predominance):
- Protein:
- Glucose:
- Gram stain:
Bacterial meningitis
- Appearance: Turbid
- Pressure: Elevated
- WBC count: >1000
- Differential count (predominance): PMNs
- Protein: Elevated
- Glucose: Low
- Gram stain: G+
Pathophysiology of pediatric bacterial meningitis:
- Bacteria enter the ____________ _____ hematogenously (across the blood brain barrier)
- Bacteria reach the meninges directly from a parameningeal infection (eg, sinusitis, mastoiditis, otitis media, brain abscess, spinal epidural abscess)
- Intense host inflammatory response (cytokines, ___, ____)
- Ultimate damage to neuron/apoptosis
Pathophysiology of pediatric bacterial meningitis:
- Bacteria enter the SUBARACHNOID SPACE hematogenously (across the blood brain barrier)
- Bacteria reach the meninges directly from a parameningeal infection (eg, sinusitis, mastoiditis, otitis media, brain abscess, spinal epidural abscess)
- Intense host inflammatory response (cytokines, IL-1, TNF-a)
- Ultimate damage to neuron/apoptosis
TQ
What is Cushing’s Triad associated with increased ICP and brain edema?
- BP increases
- HR decreases
- Respirations become irregular (signifies brainstem involvement)
List the organisms responsible for neonatal bacterial meningitis. (6)
Bacteria acquired from the maternal vaginal flora:
- Gram negative enteric flora
- Group B streptococcus (Streptococcus agalactiae) – Early onset (7 days of life)
- Staphylococcus epidermidis (coag negative Staph)
- Candida
- Listeria monocytogenes (well known but uncommon)
- Citrobacter (uncommon but associated with brain abscesses)
List the organisms responsible for bacterial meningitis in infants (>3 mo) and children: (2)
- S pneumoniae (leading cause)
- N meningitidis
TQ What would you see on LP in viral meningitis?
- WBC diff count:
- RBCs:
- Protein: Rx?
- WBC diff count: Lymphocytes
- RBCs: Increased
- Protein: Increased
Rx acyclovir
- Fever
- Racing heart
- Rapid or labored breathing
- Cool extremities
- Color changes
Sepsis in pediatric pt
Explain the pathophysiology of sepsis.
- Release of pro-inflammatory mediators exceeds the boundaries of the local infection
- Generalized inflammatory response (SIRS: Systemic Inflammatory Immune Response)
- Cytokines (tumor necrosis factor-alpha, interleukin-1)
- Complement activation
- Genetic susceptibility
Earliest and mildest manifestation of sepsis: (3)
- Hyperthermia (or hypothermia)
- Tachypnea
- Tachycardia
- Increased cardiac output
- Peripheral vasodilation
- Increased tissue oxygen consumption
- Hypermetabolic state
Warm shock
- Cardiac output falls
- Peripheral vascular resistance increases
- Shunting of blood
Cold shock
Bacterial etiologies of early-onset neonatal sepsis: (4)
- Group B streptococcus (Streptococcus agalactiae)*
- Escherichia coli
- Haemophilus influenzae
- Listeria monocytogenes
Bacterial etiologies of late-onset neonatal sepsis: (6)
- Coagulase-negative Staphylococcus (S epidermidis)
- Staphylococcus aureus
- E. coli
- Klebsiella species
- Candida species
- GBS
MC bacterial etiology of infantile meningitis worldwide:
H influenzae type b (Hib)
MC bacterial etiologies in infants and children in the United States and developed world: (5)
- E coli
- S aureus
- S pneumoniae
- N meningitides
- S pyogenes
TQ
Intrapartum antibiotic prophylaxis
- When in labor, __________ or __________ is given IV every 4 hours until delivery with at least one dose given 4 hours before birth
- Due to IAP, the rate of (early/late) onset GBS dz has decreased significantly
Intrapartum antibiotic prophylaxis
- When in labor, PENICILLIN or AMPICILLIN is given IV every 4 hours until delivery with at least one dose given 4 hours before birth
- Due to IAP, the rate of EARLY onset GBS dz has decreased significantly (IAP has no affected the rate of late onset dz)*
Occurs within the first 24 hours up to 1 week of age
Signs and symptoms
- Tachypnea
- Grunting
- Flaring
- Apnea
- Cyanosis
- Hypotension (25% of cases)
- Temperature instability
- Poor feeding
- Tachycardia
- Jaundice
- Lethargy
* Dx: (early/late) onset GBS dz
EARLY onset GBS dz Risk factors for EOD
- Maternal colonization at birth
- Preterm birth
- ROM >18 hours prior to delivery
- Lack of maternal antibodies to type specific capsular polysaccharides and protein antigens
- Chorioamnionitis
- Multiple gestation
- Nonwhite maternal race
- Intrapartum fever >38 C
- Intrauterine monitoring
- Postpartum maternal bacteremia
- Having had a previous infant with invasive GBS disease
TQ
- Generally more mildly ill upon presentation
- 65% present as bacteremia without a defined focus
- 25% to 30% present with meningitis
- Septic arthritis (hip, knee, ankle)
- Osteomyelitis (humerus most common, femur, tibia)***
- Cellulitis and adenitis
Dx: (early/late) onset GBS dz
LATE onset GBS dz