Neonatal Infection

Question 1

What is the difference between congenital and perinatal infection?

Answer 1

Congenital:

• Transmitted transplacentally
• Risk of transmission first 12-16wks
• Presents with IUGR, miscarriage, microcephaly congenital abnormalties

Perinatal:

• Transmitted at time of delivery
• Presents with sepsis picture

Question 2

What are the common congenital infections?

Answer 2

Toxoplasmosis
Other*
Rubella
CMV
Herpes simplex
Everything else**
Syphillis

• Group B Streptococcus, Listeria, Candida, Lyme disease
• *Gonorrhea, Chlamydia infection, HPV

Question 3

What are some of the risk factors for neonatal infection?

Answer 3

• Maternal Pyrexia
• Prolonged rupture of membranes
• Prematurity
• Maternal Chorioamnionitis (inflammation of the chorion and amnion)
• Maternal Group B strep colonisation
• Foul smelling liquor

Question 4

How common is CMV as a congenital infection and how does it present in the infant?

Answer 4

3/4 per 1000 live births

When an infant is infected:
• 90% are normal at birth and have normal development

• 5% develop problems later in life, mainly sensorineural hearing loss

• 5% have clinical features at birth such as hepatosplenomegaly and petechiae.
Most of this group will have neurodevelopmental disabilities
such as sensorineural hearing loss, cerebral palsy, epilepsy and cognitive impairment

Question 5

How does rubella present in the infant as a congenital infection?

Answer 5

Presentation is dependent on gestation of mother when she contracted rubella.

If contracted before 8 weeks gestation 80% of children will suffer from:

• congenital cataracts
• congenital heart disease
• deafness

As well as prematurity and low birth weight.

If contracted between 13-16 weeks ~ 30% will have impaired hearing.

If contracted after 18 weeks risk to the fetus is minimal

Question 6

What is toxoplasmosis?

Answer 6

It is a parasite which can be contracted from eating undercooked meat.

Question 7

How common is toxoplasmosis as a congenital infection?

Answer 7

0.1 per 1000 live births of these only 10% are symptomatic

Question 8

What is the presentation of clinical congenital toxoplasmosis infection?

Answer 8

• Retinopathy
• Cerebral calcification
• Hydrocephalus

These infants have long term neurological disability

Question 9

How common is group B strep?

Answer 9

10-30% of women carry faecal or vaginal Group B strep

Question 10

What can group B strep cause and how commonly does it cause it?

Answer 10

Although it is not harmful in adults it can cause both early and late onset sepsis in newborns.

In early onset sepsis (1st 48hrs) the newborn will usually present with pneumonia but may also cause septicaemia and/or meningitis. This carries a significant mortality.

Early onset sepsis from GBS occurs in 0.5-1 per 1000 live births.

Late onset sepsis is any time after 48hrs and 3 months and usually presents with meningitis or another focal infection.

Question 11

What is the management if a mother is known to be a carrier of GBS and what is the management if a child is suspected to be suffering from GBS?

Answer 11

Mother: If known to be carriers of GBS treated with prophylactic abx.

Baby:
CXR
Cultures
Full septic screen

Empirical broad spectrum antibiotics should be started immediately. If cultures are normal after 48hrs and clinical signs are normal stop abx. If abnormal continue/consider alternative abx.

Question 12

What are the common STI which can be passed to the baby via congenital/perinatal infection?

Answer 12

Chlamydia
Gonorrhoea
Syphilis
HIV
Hep B/C
Herpes

Question 13

How does Chlamydia present in neonates and how is it treated?

Answer 13

Conjunctivitis and eyelid swelling up to 2 weeks after birth.

Treat with erythromycin po.

Question 14

How does Gonorrhoea present in neonates and how is it treated?

Answer 14

40% develop ophthalmia neonatorum presents with:

• purulent discharge (from eye)
• lid swelling
• corneal haze

Occurs within 4 days of birth and needs urgent treatment to prevent blindness.

Treat with penicillin or 3rd generation cephalosporin.

Question 15

How does Syphilis present in neonates and how is it treated?

Answer 15

Rare in the UK but carries a very high rate of infant mortality.

Presents with:

• Fever
• Failure to thrive
• Irritability
• No bridge on nose
• Blistering rash which affects mouth, anus and genitalia

-Hepatosplenomegaly

Complications include:

• Blindness
• Deafness
• Facial deformity
• Neurological disability

Treated with penicillin

Question 16

How does Hep B/C present in neonates and how is it treated?

Answer 16

Hep C may cause jaundice.

Hep B can rarely causes jaundice but a proportion develop chronic Hep B which may eventually develop into cirrhosis.

Treatment is immunisation with 24hrs of birth.

Question 17

How does Herpes present in neonates and how is it treated?

Answer 17

Presents up to 4 weeks with:
-localised herpetic lesions on the skin or eye
Or
-with encephalitis
Or 
-disseminated disease

Mortality due to disseminated disease is very high even with treatment and carries a significant morbidity in those that do survive.

If you no mother suffers from genital herpes ideal treatment is Caesarean + anti-virals.

Question 18

How does HIV present in neonates and how is it managed?

Answer 18

Diagnosis is needed to be done by HIV PCR as HIV antibodies may be maternal in 1st 18month of life therefore may give a false positive.

In affected children whom aren’t treated it presents with:
Lymphadenopathy, hepatosplenomegaly, recurrent fever, parotid swelling, thrombocytopenia.

Treatment is based around viral load and CD4 count.
Treatment should be:
- a combination of Anti retro viral drugs
- co-trimaxazole for pneumocystis pneumonia prophylaxis
- full immunisation (except BCG as is live and may cause disseminated disease)

Question 19

What methods should be take to prevent transmission to the baby in a HIV+ve mother?

Answer 19

Use of maternal antenatal, perinatal and postnatal antiretroviral drugs to achieve an undetectable maternal viral load at the time of delivery.

Avoidance of breast feeding.

Pre-labour caesarean section if the mother’s viral load is detectable close to the time of delivery.

If undetectable active management of labour to avoid prolong rupture of membranes and unnecessary instrumentation.

Question 20

What should be included in a septic screen?

Answer 20

• Urine culture and dip

• FBC
• U&E’s with glucose
• Blood culture
• Blood gas
• CRP
• Chest radiograph
• CT or MRI (if suspected meningitis)

• Lumbar puncture (if suspected meningitis, check for raised ICP 1st)