11/14/24, 10\:54 AM Neonatal Sepsis

Neonatal Sepsis

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Neonatal sepsis\: life-threatening infection in the
onset (after 48-72 hours).
Incidence\: 6.1 per 1000 live births and 48.8 per 1000 neonatal unit admissions in the UK.
Aetiology\: early-onset usually from maternal genital tract organisms (e.g., GBS, E . c o l i ), late-onset from environmental
organisms (e.g., coagulase-negative staphylococci, S t a p h . a u r e u s ).
Risk factors\: prematurity, low birth weight, prolonged rupture of membranes, maternal GBS colonisation, maternal
infection, invasive procedures, poor infection control practices in low/middle-income countries.
Symptoms\: non-speci
tachycardia/bradycardia, poor perfusion, poor feeding, abdominal distension, irritability, seizures, bulging fontanelle.
History\: focus on pregnancy (fetal concerns, maternal infections), labour and delivery (duration of membrane rupture,
maternal fever), birth (gestational age, birth weight, Apgar scores), and postnatal period (feeding issues, urine/meconium
passage, interventions).
Examination\: thorough neonatal assessment for signs of sepsis; general (fever, lethargy), respiratory (distress, cyanosis),
cardiovascular (tachycardia, hypotension), gastrointestinal (poor feeding, distension), neurological (irritability, seizures).
Di
necrotising enterocolitis, congenital pneumonia, congenital heart disease, haemolytic disease of the newborn, metabolic
diseases.
Investigations\: FBC, CRP, blood cultures, lumbar puncture, urine culture, swabs, chest/abdominal X-rays, scoring systems
(e.g., Kaiser Permanente Neonatal Early-Onset Sepsis Calculator).
Management\:
Early-onset sepsis\: benzylpenicillin plus gentamicin (add cefotaxime if Gram-negative infection).
Late-onset sepsis\:
Speci
antifungal for suspected fungal sepsis, add aciclovir for suspected HSV infection.
Complications\: poor cognitive development, visual/hearing de
Prognosis\: variable; early detection and prompt treatment are crucial to improve outcomes and reduce complications.
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A comprehensive topic overview

Introduction

Neonatal sepsis is a life-threatening condition caused by systemic bacterial, viral or fungal infection within the
of life. It is classi
sepsis (occurring after the
1
management. Neonatal sepsis is a major cause of neonatal mortality and morbidity and has an incidence of 6.1 per 1000
live births and 48.8 per 1000 admissions to the neonatal unit in the UK. 2
This article aims to give you an overview of the key
points regarding this important neonatal condition.
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Aetiology and risk factors

1,2
Neonates are susceptible to infection as the newborn immune system is immature. This is especially true in preterm
infants. Early-onset sepsis is caused by infection with organisms from the maternal genital tract, while late-onset sepsis is
caused by organisms acquired through interaction with the home or hospital environment. The most common organisms
and important risk factors are compared below (Table 1).
Table 1. Comparing risk factors and organisms for early and late-onset neonatal sepsis.
Early-Onset Sepsis (\< 48-72h) Late-Onset Sepsis (> 48-72h)
Prematurity
Low birth weight
Prolonged rupture of
membranes (> 18 hours)
Prematurity
Low birth weight
Risk factors
Maternal Group-B
streptococcus (GBS)
colonisation
Invasive procedures (e.g. IV
access or intubation)
Maternal infection during
labour (e.g. chorioamnionitis)
Most
common*
GBS (~40%)
E . c o l i (~20%)
L i s t e r i a m o n o c y t o g e n e s
Coagulase-negative
staphylococci (e.g. S t a p h .
e p i d e r m i d i s ) (~60%)
S t a p h . a u r e u s (~6%)
E . c o l i (~6%)
Other Gram-negative
organisms (e.g. K l e b s i e l l a ,
E n t e r o b a c t e r and
P s e u d o m o n a s )
While neonatal sepsis is commonly associated with bacterial infection, viruses and fungi can cause sepsis too. These
usually result in late-onset sepsis. The most common viruses are herpes simplex virus (HSV) and enteroviruses, and the
most common fungus is C a n d i d a a l b i c a n s .
*A global perspective\: It is worth noting that, although the above table represents the commonest organisms in high-
income countries such as the UK, K l e b s i e l l a species, E . c o l i and S t a p h . a u r e u s are signi
sepsis in low and middle-income countries, while GBS is relatively uncommon. 3
The preponderance of these Gram-
negative organisms may relate to poor infection prevention and control practices around the time of delivery and are likely
acquired from the environment, rather than vertically from the mother.

Clinical features

The clinical features of neonatal sepsis may be non-speci
condition among your list of di

History

A focussed history should be obtained from the obstetric team, the parents and/or the baby’s medical records. The aim of
the history is to identify any risk factors for neonatal sepsis, as mentioned above.
Speci
Pregnancy\:
Any fetal concerns during the pregnancy (e.g. growth problems or ultrasound scan abnormalities)?
Any maternal illness during pregnancy (particularly infections)?
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Has the mum previously given birth to a baby who developed an invasive infection?
Labour and delivery\:
What was the duration of membrane rupture?
Did the mum develop a fever during labour?
Were prophylactic antibiotics for GBS recommended and, if so, were they given?
Birth\:
What gestational age was the baby born at?
What was the baby’s birth weight?
What were the baby’s Apgar scores?
Were any abnormalities noticed during the baby check?
Since birth\:
Have there been any feeding problems?
Has the baby passed urine and meconium?
Has the baby received any interventions?
Have the parents or nursing sta
Examination1,4
Any sick neonate should undergo a thorough clinical examination (see our neonatal examination guide).
Clinical features of neonatal sepsis are shown below, categorised by body system.
General\:
Fever or temperature instability
Lethargy
Jaundice
Hypo- or hyperglycaemia
Respiratory\:
Apnoea
Respiratory distress
Cyanosis
Cardiovascular\:
Tachycardia or bradycardia
Hypotension
Poor perfusion and prolonged capillary re
Gastrointestinal\:
Poor feeding
Abdominal distention
Neurological (consider meningitis)\:
Irritability
Seizures
Bulging fontanelle (Figure 1)
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Figure 1.Anatomy of the neonatal skull. Note the anterior fontanelle, which may appear “bulged” in cases of neonatal sepsis.
8

Di

As the presentation of neonatal sepsis is generally non-speci
the di
Possible di
Congenital infections* (e.g. TORCH)\: Toxoplasmosis, Other (e.g. syphilis, varicella-zoster, parvovirus B19, HIV), Rubella,
Cytomegalovirus and Herpes simplex virus.
Respiratory distress syndrome (RDS)
Transient tachypnoea of the newborn (TTN)
Necrotising enterocolitis (NEC)
Congenital pneumonia
Congenital heart disease
Haemolytic disease of the newborn (HDN)
Metabolic diseases (e.g. galactosaemia)
*A note on terminology\:
‘congenital infection’ refers to an infection that is acquired by the fetus i n u t e r o (usually through the
placenta), whereas ‘neonatal infection’ refers to infection acquired during or after delivery.
5

Investigations

4,6
Laboratory investigations
Full blood count (FBC) and CRP
Blood cultures
Lumbar puncture
Urine culture (‘in-out’ catheter or suprapubic aspiration)
Swabs of speci
Imaging
Chest X-ray (if respiratory signs present on examination)
Abdominal X-ray (if abdominal signs present on examination)
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Other investigations
More recently, scoring systems have been developed in an attempt to predict the risk of neonatal sepsis, guide
management and reduce unnecessary antibiotic exposure. Currently, the most commonly used is the Kaiser Permanente
Neonatal Early-Onset Sepsis Calculator. This score combines maternal risk factors (such as maternal temperature, duration
of rupture of membrane and maternal GBS status) with the clinical appearance of the baby to estimate the risk of early-
onset sepsis at birth and provide a recommended management plan.

Management

4,6
Neonatal sepsis is a life-threatening emergency. As such, prompt empirical management with broad-spectrum antibiotics
is warranted whilst awaiting investigation results. The exact choice of antibiotic therapy can get complicated and depends
on the local sensitivities of the neonatal unit you are working in (always consult local guidelines and the BNFC). However, in
the interest of simplicity, some common empirical therapy options are listed below.

Early-onset sepsis

Benzylpenicillin plus gentamicin (IV)
Add cefotaxime (IV) if there is microbiological evidence of Gram-negative infection

Late-onset sepsis

Flucloxacillin (or vancomycin) plus gentamicin (IV)

Speci

Give amoxicillin and cefotaxime (IV) if meningitis is suspected
Add metronidazole if NEC is suspected
Add an antifungal (e.g. amphotericin B) if fungal sepsis is suspected (high-risk baby with a negative blood culture)
Add aciclovir (IV) if HSV infection is suspected (e.g. vesicular rash, late-onset sepsis with respiratory disease or sepsis not
responding to antibiotics)
The choice of antibiotics should be reviewed and rationalised once culture results become available. Even if cultures are
negative, antibiotics are often continued as neonates can deteriorate quickly and the blood culture may be falsely negative
due to a low bacterial load, an inadequate volume of blood in the sample, or previous antibiotic exposure in the mother or
baby. If at 36 hours tests are negative for infection and the baby appears well, antibiotics can be stopped.

Prognosis and complications

Complications of neonatal sepsis\:
Poor cognitive development
Visual or hearing de
Cerebral palsy
Bronchopulmonary dysplasia (BPD)
Death
7

References

Shane A.L. et al. Neonatal sepsis. 2017 Oct;390(10104)\:1770-80. Available from\: [LINK].
Cailes B. et al. Epidemiology of UK neonatal infections\: the neonIN infection surveillance network. A r c h D i s C h i l d F e t a l
N e o n a t a l E d . 2018 Nov;103(6)\:F547-53. Available from\: [LINK].
Zaidi A.K.M. et al. Pathogens associated with sepsis in newborns and young infants in developing countries. Pediatr Infect
Dis J. 2009 Jan;28(1 Suppl)\:S10-8. Available from\: [LINK].
National Institute for Health and Care Excellence (NICE). Neonatal infection (early onset)\: antibiotics for prevention and
treatment (CG149) [Internet]. 2012 [cited 12 June 2020]. Available from\: [LINK].
https\://app.geekymedics.com/notebook/2605/ 5/611/14/24, 10\:54 AM Neonatal Sepsis
Vergnano S. and Heath P.T. Fetal and neonatal infections. 2017 Nov;45(11)\:P715-22. Available from\: [LINK].
Greater Glasgow and Clyde Paediatric Guidelines. 2018. Antibiotic guidelines for the neonatal unit [Internet]. 2018 [cited 12
June 2020]. Available from\: [LINK].
Singh M. and Gray C.P. Neonatal sepsis [Internet]. 2019 [cited 12 June 2020]. Available from\: [LINK].
Xxjamesxx. Cranial sutures shown from the top of the head. Licence\: [CC BY-SA 3.0]. Available from\: [LINK].

Reviewer

Dr Felicity Fitzgerald
Academic Clinical Lecturer and Senior Registrar in Paediatric Infectious Diseases

Related notes

Attention De
Autism Spectrum Disorder (ASD)
Biliary Atresia
Bronchiolitis
Cerebral Palsy

Test yourself

Contents

Introduction
Aetiology and risk factors 1,2
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