Transcript Neonatal Sepsis Steve Spencer, MD Objectives • Review of terminologies associated with neonatal infections • Review risk factors for neonatal infections • Review presentations of.

Neonatal Sepsis
Steve Spencer, MD
Objectives
• Review of terminologies associated with
neonatal infections
• Review risk factors for neonatal infections
• Review presentations of neonatal sepsis
• Review most common organisms and
treatments
• We will concentrate on the child <3 months of
age
Cases
• You are on-call
tonight when the ER
calls with two kids
Cases
• Kid 1
• 9 week old, term
baby
• 100.6 temp
• Looks well
• CBC WNL
• UA clean
• Everyone at home
with colds
• Kid 2
• 12 day old, term
baby
• Fever to 101
• Jaundiced
• Seizures
• WBC of 3.2 K
• PLT of 89
Do you treat these kids the same or different and why?
Your Text
Terminologies
• Rule out sepsis
• Neonate with fever
• Neonatal fever
• Neonatal sepsis
• Serious Bacterial Infection (SBI)
• Occult Bacteremia
• Neonate- the first month 28days of life
• Infant- up to one year
Back When I was an Intern…..
• Any kid 3 months or less with fever got
admitted
• Kids stayed longer
• If it sneezed, writhed, wiggled or
wheezed, it got an LP
• Kids had to crawl seven miles through
the snow, up hill both ways, to
daycare…..
Age Groups
• Currently ages 0-28 days automatically
admitted by most clinicians
• 1-3 months is a grey zone guided by
clinical opinion
• Greater than three months generally not
admitted
Why Have Recommendations
Changed?
• GBS prophylaxis
• Immunizations
• HIB, Pneumococcus
• Better understanding of neonatal
physiology
• Better laboratory techniques
• Better understanding of the disease
• Different antibiotics
Definition of Fever
• “Gold Standard” is generally thought of
as 100.4 (38.0) rectally with a glass
mercury thermometer
• Lots of ways to take a baby’s
temperature
• I recommend using a quality thermometer
• When in doubt, let the pros sort it out
• In Newborn Nursery, need to counsel
parents about significance of fever in
neonate
Why the Worry?
• Neonatal immune system immature
• Perinatal exposure to pathogens via birth
canal
• High rate of infection in kids less than 3
months with fevers
• >4% age 0-28 days with bacteremia or meningitis
(drops to 1% by 3 months)
• Almost 10% with UTI
• Rates increase with degree of fever
• 39C with >10% rate of bacteremia
• Well appearing infant may have an infection
Why not admit everybody?
• Not without risk of hospital acquired
infection
• Cost
• Lost time to parents at work
• Family stress
• etc
What data supports our
practice?
• Rochester criteria
• Philadelphia criteria
• Boston criteria
• Etc
Risk Factors
• Prematurity and low birth weight
• Maternal GBS
• Prolonged rupture of membranes
• Maternal chorioamnionitis
• Sibling with sepsis
• Meconium at delivery
• Need for resuscitation
• Male child
• Multiple gestation
“Early” Pathogens (first
week)
• Group B Strep (GBS)
• Incidence used to be 4-6/1000 live births (0.4%)
• Now <0.1% after prenatal screening guidelines
• E. coli
• Every few decades flips back and forth with GBS
as most common cause
• Gram negative rods (esp. in urine)
• Occasional Salmonella sepsis
• Listeria monocytogenes
• Herpes Simplex
• Enterovirus
“Late” Pathogens (~1-2
weeks)
• GBS or group A strep
• Enterics/Enterococcus in urine
• HSV
• Enterovirus, RSV, Flu
Community Acquired (after 4-6
weeks)
• Pneumococcus
• Meningococcus
• GABHS
• Haemophilus influenzae (HIB) not really a
problem anymore
Signs/Symptoms
Most by themselves mean little, but three (or two) strikes and you are Out!
• Temperature
irregularity
• Fever
• Hypothermia
• Tone and Behavior
•
•
•
•
•
Poor tone
Weak suck
Shrill cry
Weak cry
Irritability
• Skin
•
•
•
•
•
•
Poor perfusion
Cyanosis
Mottling
Pallor
Petechiae
Unexplained
jaundice
Signs/Symptoms
• Feeding Problems • Cardiopulmonary
• Vomiting
• Diarrhea
• Abdominal
distension
• Hypo or
Hyperglycemia
• Tachypnea
• Retractions
• Tachycardia for
age
• Bradycardia in
first few days of
life
• Hypotension for
age
• Low PO2
Signs/Symptoms
• Sunken fontanelle
• Bulging or pulsating fontanelle
• Neck stiffness CAN NOT be used
• Babies can be bacteremic but look well
• Presence of a “cold” does not change
anything
PIDJ April 2005
• Study in India found
that any two of these
signs had an almost
100% sensitivity for
sepsis and over 90%
mortality
•
•
•
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•
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Reduced sucking
Weak cry
Cool extremities
Vomiting
Poor tone
Retractions
Labs
• Normal WBC (5-15K) is better than high WBC
is better than very high WBC (over 35K)
which is better than very low WBC (<5K)
• Less than 28 days- blood, urine, CSF cultures
+/- stool
• Get urine culture, even if UA WNL
• >28 days see handout
• CXR if respiratory symptoms
Lab Dilemmas- Urine collection
• Don’t use bag urines!
• A negative culture on a bag urine is negative
• A positive means nothing
• Cath or Suprapubic aspirate?
• SPA- any growth is considered a positive
• Cath
• Can have false positives, especially if uncirc’d male
• New debates on what constitutes a positive culture
• Most references use >10K CFU’s as positive, some use as
little as 1K (equals one plaque)
• Microbiologists feel we should use 100K on all samples
regardless of source
Lab Dilemmas- The Bloody Tap
The Bloody Tap
• Don’t ask me, you should have gotten it
right the first time
The Bloody Tap
• No right answer
• Results can vary based on the amount
of blood in amount of CSF, what is the
HCT, what is the peripheral WBC count
etc. Some use CBC to CSF ratios.
• Sometimes seems like too many WBC’s
or seems OK
• Sometimes just need to re-tap
Treatment
• Age 0 to ~4-6 weeks
• Ampicillin/Aminoglycoside
• Ampicillin/Cefotaxime
• Amp kills GBS and Listeria
• Gent and Cefotaxime for GNR’s
• Ceftriaxone not used- causes neonatal
hepatitis and biliary sludging
Aminoglycosides
• Disadvantages
• Ototoxicity
• Nephrotoxicity
• Need for levels
• Advantages
• Little resistance
• Cheap (30 cents or so
a dose)
• Highly concentrated
in urine
• No need for levels if
QD dosing in a 48
hour admission
Treatment
• After 4-6 weeks, ampicillin and a 3rd
generation cephalosporin
• Offers better coverage for community
acquired organisms
• At 4-8 weeks, switch to cephalosporin
alone.
What About Herpes?
• Some clinicians begin acyclovir on all
neonatal admissions for fever
• We use the guideline of “Fever Plus”
• HSV is rare & tends to present in certain ways
• Fever in addition to
• Hepatitis/jaundice
• Meningitis
• Seizures
• Thrombocytopenia
• Vesicles
• Rash/purpera
HSV Risk Factors
• Maternal history- only present in
• Maternal primary infection- as many as
50% of babies infected
• Active lesions
• ROM > 4-6 hours
• Fetal scalp electrode
• Prematurity
• Caregiver with cold sore/fever blister
HSV in Neonate
• Three types
• SEM (Skin, Eye, Mucous membranes)- 15%
• Isolated CNS- 35%
• Disseminated (+/- CNS)- 50%
• 75% HSV-2 25% HSV-1
• Incidence 1:1K-5K births
HSV timing
• SEM (Skin, Eye, Mucous membranes)can be early
• Isolated CNS- 2-3 weeks
• Disseminated (+/- CNS, +/-SEM)- ~1
week
HSV Labs- three points
• CSF PCR alone DOES NOT rule out
HSV
• CSF PCR alone DOES NOT rule out
HSV
• CSF PCR alone DOES NOT rule out
HSV
HSV Labs- if do it, do it right
• CSF for PCR (>98% sensitive, >95%
specific) and/or culture (30-50%)
• CSF tends to be “bloody”– 100-200 RBC
with elevated WBC
• Mucous membrane cultures
• Eyes, ears, anus, mouth, nose, vesicles if
present, some add urine
• In nursery, wait 24 hours after birth to
culture (indicates active infection)
HSV Labs cont.
• LFT’s
• I now get for any R/O SBI kid that I am worried
enough about to get a BMP
• Serial CBC’s
• Thrombocytopenia
• Leukopenia
• Tzank smear of lesions(~40% sensitive, not
specific)
• DFA or EIA of lesions (80% sensitive)
• Serology NOT useful
Imaging
• Classic CT/MRI temporal lobe lesion
but may have many
presentations to
include
hydrocephalus
HSV treatment
• Acyclovir 20mg/kg/dose Q8 hrs
• SEM only- 14 days
• Disseminated (no CNS)- 21 days
• CNS- at least 21 days (PCR must clear)
Cases
• Kid 1
• 9 week old, term
baby
• 100.6 temp
• Looks well
• CBC WNL
• UA clean
• Everyone at home
with colds
• Kid 2
• 12 day old, term
baby
• Fever to 101
• Jaundiced
• Seizures
• WBC of 3.2 K
• PLT of 89