Neonatal sepsis
Dr. Saad A. Alsaedi
Objectives
• Definition
• Classification
• Risk factors
• Causative organism
• Clinical presentation of early and late onset sepsis
• Differential diagnosis
• Management (including investigations and treatment)
Neonatal Sepsis
What is it?
Clinical syndrome of systemic illness
accompanied by bacteremia occurring in the
first month of life
Neonatal Sepsis
Incidence:
1-8/1000 live births Mortality:
15-30/1000 live births for infants < 1500g
Neonatal sepsis
1- Prenatally acquired
2- Early sepsis (1-7 days of age)
3- Late sepsis (1-3 weeks of age)
Risk factors
Early onset sepsis:
• Prematurity and low birth weight
• PROM
• Group B streptcoccal carrier mother
• Maternal peripartum fever
• Chorioamnionitis
• Resuscitation at birth
• Multiple gestation
• Invasive procedures
Risk factors
Late onset sepsis:
• Prematurity
• Invasive procedures (central lines, ETT …)
• Poor infection control measures in the NICU
• overcrowding
• TPN
Causative organisms
Early Onset
– Group B streptococcus
– Gram-negative enterics (esp. E. coli)
– Listeria monocytogenes, Staphylococcus, other streptococci (entercocci), anaerobes
Causative organisms
Nosocomial infection – Varies by nursery
– Staphylococcus epidermidis
– Pseudomonas, Klebsiella, Serratia Proteus
– Fungi (candida ….)
Clinical presentation
• nonspecific
• Temperature instability
Hypo/hyperthermia
• Change in behavior
Lethargy, irritability, changes in tone
• Skin changes
Poor perfusion, mottling, cyanosis, pallor, petechiae, rashes, jaundice
Clinical presentation
• Feeding problems
- Intolerance, vomiting, diarrhea, abdominal distension
• Cardiorespirarory
- Tachypnea, grunting, flaring, retractions, apnea, tachycardia, hypotension
• Metabolic
- Hypo or hyperglycemia, metabolic acidosis
Early Onset
• First 5-7 days of life
• Usually multisystem
• fulminant illness
• prominent respiratory symptoms
Early Onset
• High mortality rate
5-20%
• Typically acquired during intrapartum period from maternal genital tract
• Associated with maternal chorioamnionitis
Late Onset
• May occur as early as 5 days but is most common after the first week of life
• Less association with obstetric
complications
Late Onset
• Usually have an identifiable focus Most often sepsis or meningitis
• Acquired from
- maternal genital tract or
- human contact
Differential diagnosis of neonatal sepsis
It depends on the clinical presentation
– RDS
– Metabolic disease
– Hematologic disease – CNS disease
– Cardiac disease
– Other infectious processes (i.e. TORCH)
Nosocomial sepsis
• Occurs in high-risk newborns
• Pathogenesis is related to
– the underlying illness of the infant – the flora in the NICU environment – invasive monitoring
• Breaks in the barrier function of the skin and intestine allow for opportunistic
infection
Diagnosis
Cultures:
– Blood
Confirms sepsis
94% grow by 48 hours of age
Diagnosis
Urine:
Don’t need in infants <24 hours old because
UTIs are exceedingly rare in this age group
CSF:
Adjunctive lab tests
White blood cell count and differential
– Neutropenia can be an ominous sign
– I:T ratio > 0.2 is of good predictive value – Serial values can establish a trend
Platelet count
– thrombocytopenia
Adjunctive lab tests
Acute phase reactants
– CRP rises early, monitor serial values – ESR rises late
Other tests:
- bilirubin, glucose, sodium
Radiology
CXR
– Obtain in infants with respiratory symptoms
– Difficult to distinguish GBS or Listeria
pneumonia from uncomplicated RDS
Management
Antibiotics
– Early onset sepsis:
ampicillin and gentamicin – Nosocomial sepsis:
differs from NICU to other
cloxacillin and gentamicin or cefotaxime – Change based on culture sensitivities
– Don’t forget to check drugs levels
Supportive therapy
Respiratory
Oxygen and ventilation as necessary
Cardiovascular
• Support blood pressure with volume expanders and/or pressors
• Hematologic
• Treat DIC with FFP
• Platelets transfusion
• PRBC transfusion
Supportive therapy
CNS
- Treat seizures with phenobarbital
- Watch for signs of SIADH (decreased UOP, hyponatremia) and treat with fluid restriction
Metabolic
- Treat hypoglycemia/hyperglycemia and metabolic acidosis
