Summary

Neonatal sepsis is systemic bacterial infection in the first 28 days of life. It is a major cause of neonatal morbidity and mortality. Early-onset sepsis (EOS, under 72 hours) is usually vertically transmitted from maternal flora (Group B Streptococcus, E. coli). Late-onset sepsis (LOS, over 72 hours) may be nosocomial or community-acquired. Signs are often non-specific and subtle. A low threshold for investigation and empirical treatment is essential.

Key Facts

• Incidence: 1-8 per 1000 live births (EOS); higher in VLBW infants
• Mortality: 10-20% overall; up to 50% in VLBW infants
• Early-onset (under 72h): GBS (43%), E. coli (29%) — maternal risk factors
• Late-onset (over 72h): Coagulase-negative staphylococci, S. aureus, Gram-negatives
• CRP: May be normal in first 6-12 hours — serial measurement essential
• Antibiotics: Give within 1 hour of decision to treat

Clinical Pearls

Sick neonate = sepsis until proven otherwise — signs are non-specific

Hypothermia (under 36°C) can be a sign of sepsis in neonates — not just fever

Normal initial CRP does NOT exclude sepsis — always repeat at 18-24 hours

Why This Matters Clinically

Neonatal sepsis progresses rapidly and can be fatal within hours. Early recognition and treatment are critical. The non-specific nature of signs means clinicians must maintain a high index of suspicion. NICE guidance on risk stratification helps identify which babies need antibiotics, observation, or reassurance.

Structured Approach

1. General Observation:

• Activity level, responsiveness
• Colour (pallor, mottling, cyanosis, jaundice)
• Handling response (floppy, irritable)

2. Vital Signs:

• Temperature (axillary): Normal 36.5-37.5°C
• Heart rate: Normal 110-160 bpm
• Respiratory rate: Normal 30-60 bpm
• SpO₂, blood pressure

3. Perfusion Assessment:

• Capillary refill time (under 3 seconds normal)
• Peripheral temperature
• Urine output (under 1 ml/kg/hr concerning)

4. Focused Examination:

• Skin: Petechiae, pustules, omphalitis
• Chest: Work of breathing, air entry
• Abdomen: Distension, liver/spleen size
• CNS: Fontanelle, tone, movement, seizures
• Lines/Devices: Signs of infection at insertion sites

Early vs Late-Onset Sepsis

NICE Risk Stratification for EOS

Red Flags (Start Antibiotics Immediately):

• Clinical signs of neonatal sepsis
• Suspected or confirmed maternal invasive bacterial infection
• Invasive GBS in previous infant

Non-Red-Flag Risk Factors (Consider Need for Antibiotics):

• PROM over 18 hours before onset of labour at term
• Preterm birth following spontaneous labour
• Confirmed maternal GBS colonisation with inadequate IAP
• Suspected or confirmed rupture of membranes more than 24 hours in preterm baby
• Intrapartum fever over 38°C

Mortality

Long-Term Outcomes

• Higher rates of cerebral palsy in survivors of neonatal meningitis
• Hearing and vision impairment
• Developmental delay

Key Guidelines

1. NICE NG195: Neonatal Infection (Early-Onset) (2021) — Risk stratification and management
2. RCOG Green-Top GTG 36: GBS Prevention (2017) — Intrapartum antibiotic prophylaxis
3. BAPM Framework for Late-Onset Sepsis

Key Evidence

• Kaiser Permanente EOS Calculator validated for risk stratification
• Intrapartum antibiotic prophylaxis reduces EOS by 80% in GBS-colonised mothers

What is Neonatal Sepsis?

Neonatal sepsis is a serious bacterial infection in newborn babies. It can make babies very unwell very quickly. Because the signs are not always obvious (like just being extra sleepy or not feeding well), doctors do blood tests if they are worried.

Warning Signs

• Baby not feeding well or refusing feeds
• Very sleepy or hard to wake
• Temperature too high (over 38°C) or too low (under 36°C)
• Fast breathing or pauses in breathing
• Pale, blotchy, or blue skin

Treatment

• Antibiotics given through a drip (IV)
• Usually kept in hospital for observation
• Blood tests to check for infection

Resources

• NHS
• Tommy's
• Bliss (premature baby charity)