• Bacterial sepsis is a major problem in the newborn unit. Approximately 10% of all neonates admitted to NICU are treated with antibiotics for suspected sepsis.
• A bacterial cause is found in less than 10% of these infants (1-5 per 1000 live births).
• The incidence of sepsis is higher in preterm infants, especially the very low birthweight infant (<1500g).
• Common organisms identified are coagulase negative Staphylococci (28%*), Staphylococcus aureus (19%*), Streptococcus agalactiae (10%*) and Escherichia coli (5%*).
• Other important pathogens include Listeria monocytogenes, Streptococcus pneumoniae, Haemophilus influenza and other Gram-negative organisms (total of 20%*).
• The clinical presentation of sepsis in the newborn is often non-specific; however, there may be an acute deterioration.

* Figures for blood stream infections within NICU at NWH 1998.

Classification of Neonatal Sepsis

When should Antibiotics be Given?

• Antibiotics should be considered in any baby with signs of sepsis, particularly in the presence of risk factors.
• Risk factors may be an indication for investigation - particularly a full blood count - but are not in themselves an indication for antibiotics if the baby is born at term and is clinically well.
• This is not a complete list and if there are any doubts a more senior member of staff should be consulted.

Risk Factors for Sepsis

• Prolonged rupture of membranes (>24 hours).
• Prematurity (especially in association with PROM).
• Preterm labour with no adequate explanation
• Fetal distress without adequate explanation (fetal heart rate abnormalities especially fetal tachycardia, passage of meconium).
• Maternal fever or other evidence of infection.
• Foul smelling amniotic fluid or malodorous baby
• Indwelling vascular catheter

Signs of Sepsis in the Newborn

• Fever, hypothermia and/or temperature instability.
• Respiratory distress.
• Apnoea and bradycardia
• Cyanotic episodes
• Lethargy, irritability, poor feeding.
• Unexplained high/low or unstable blood sugars
• Abdominal distension and bile-stained aspirates
• Unexplained jaundice
• Umbilical flare, skin rashes

What Investigations Should be Performed?

• Full blood count.
• Differential white cell count (Normal WBC 10-30,000 x 10⁹/L) and percentage left shift (immature neutrophils/total neutrophil count).
  • If >20% this is moderately predictive of sepsis.
  • A low WCC especially with neutropenia is also suspicious of sepsis.
• Blood cultures.
• Chest radiograph
• A C-Reactive Protein (CRP) may be indicated.
• On occasion, skin/wound swabs and gastric aspirate (at birth only).
• CSF may be needed in some cases - discuss with specialist.

The following investigations may need to be considered depending on the organism isolated.

Late onset sepsis:  In addition to the above consider

• Blood culture taken through central line.
• Lumbar puncture and CSF for microbiology/biochemistry.
• Urine by suprapubic aspirate or catheter.

Antibiotic Use in Suspected Sepsis

• Review clinical progress and microbiology results at 48 hours.
  • If cultures negative consider stopping therapy.
  • Continue therapy if cultures positive or sepsis very likely.
• Add metronidazole if suspicion of anaerobic infection (e.g. intra-abdominal sepsis, NEC).
• Consider vancomycin for coagulase negative Staphylococcal sepsis, especially if infant unwell or central line infection with line staying in. Discuss with specialist first.
• Change to cefotaxime if neonatal meningitis. Discuss with specialist first.

Duration of Treatment

References