perinatal infection

Question 1

What are clinical features of congenital rubella syndrome

Answer 1

Sensorineuronal deafness
catarcts
blindness
endocrine problems 
encephalitis

Question 2

Infection risk of rubella in pregnacy

Answer 2

<11 weeks - 100% chance of transmission

>20 weeks no risk

Question 3

How to detect syphilis

Answer 3

Treponema antibodies (EIA)

Question 4

Mx of prenatal syphilis

Answer 4

contact sexual health clinic for track and trace
IM benzyl penicillin
beware of Jarish-Herxheimer reaction

Question 5

How to diagnose toxoplasma gondii

Answer 5

Sabin feldman dye test

Or after abnormal US do amniocentesis and PCR

Question 6

Features of foetal CMV infection

Answer 6

Growth restriction
microcephaly
intracranial calcification
Hydrops

can also cause anaemia, splenomegaly, hepatomegaly

Question 7

Diagnosis of CMV

Answer 7

Need to have a positive finding of CMV Ab in a lady who was previously negative
If foetal infection suspected do amniocentesis and PCR

Question 8

Prevention of VZV transmission in pregnancy

Answer 8

if negative avoid contact during pregnancy

Question 9

Mx if VZV -ve comes into contact with +ve

How long are they considered infectious for?

Answer 9

bear in mind that virus is active 2 days before rash develops
Give VZIg (effective up to 10 days after contact)

Considered infectious for 21 days without Ig
28 days with Ig

Question 10

Mx of chicken pox in pregnancy

Answer 10

Give aciclovir if >20 weeks and present within 24 hours of onset of rash

AND

Adivce to avoid pregnant women or neonates til lesions crusted over
Refer for US assessment 5 weeks after the infection or at 16-20 weeks

Question 11

Diagnosis of congential varidella syndrome

Answer 11

(RARE)
at least one of:
scarring in dermatomal distribution
limb hypoplasia
Eye defects
neuro defects

No cases reported if infection happens after 28 weeks

Question 12

Mx of VZV at delivery

Answer 12

If elective delay deliver until 5-7 days after onset of rash
IF:
delivery within 7 days of rash developing
or rash delevops less than 7 days after delivery
give VZIg and monitor for 28 days
ALSO DO EYE EXAM

Question 13

Complications of congenital parvovirus

Answer 13

Child becomes anaemic, get high output cardiac failure and liver congestion –> hydrops

Question 14

Mx of parvovirus

Answer 14

Conservative
Refer to obstetric clinic within 4 weeks
If anaemic or signs of hydrops:
Expectant - 50% recover fine 
in utero transfusion - (always offer if infection occurs in first 20 weeks, risk of foetal loss high)

Question 15

What raises suspicion of listeria

Answer 15

meconium staining

Question 16

Mx of listeria

Answer 16

IV amoxicillin for 2 weeks

Advice about prevention

Question 17

Why can malaria be missed antenatally

Answer 17

Can sequestrate blood in placenta

Question 18

What are the three subgroups of neonatal herpes

Answer 18

(can be caused by HSV1+2)

• localised to eyes and mouth
• localised to CNS only
• disseminate inter organ failure

Question 19

When is the greatest risk with HSV

Answer 19

Contracting primary infetion

especiallly if within 6 weeks of delivery

Question 20

Mx of first episode HSV

Answer 20

Refer to gum clinic
If first episode:
treat with oral aciclovir 5 TDS for 5 days
If it occurred in first or second trimester tx with aciclovir from 36 weeks to delivery
If it occured in 3rd trimester
continue oral aciclovir
recommend c section
if vaginal then give IV aciclovir

Question 21

Mx of recurrent episode of HSV

What notes do you have to make for delivery?

Answer 21

daily suppressive aciclovir from 36 weeks
offer vaginal delivery
avoid ARM + invasive procedures during labour

Question 22

RF for requiring GBS prophylaxis

Answer 22

Intrapartum fever 
Prolonged rupture of membrane (18 hours)
<37 weeks
Hx of infant w/ GBS 
detection of GBS on swab or GBS bacteriuria

Question 23

Mx GBS

Answer 23

Intrapartum Abx (IV benzylpenicillin)
Don’t need to if going for C -section and labour hasn’t started and membrane hasn’t ruptured
Neonatal monitoring for 12 hours

Question 24

When does HIV transmission usually occur

Answer 24

Late 3rd trimester
Delivery
When breastfeeding

Question 25

Antenatal mx of maternal HIV

Answer 25

If known: see HIV + obs clinic every 1-2 weeks, monitor viral load every 2-4 weeks, continue ART
If incidental - same and start ART by 24 weeks

Question 26

Intrapartum mx of HIV

Answer 26

If viral load <50 copies/ml - can do vaginal birth

If >50/ml or w/ coexisting hep c- aim for c section before 38 weeks w/ iv zidovudine

Question 27

Postnatal mx of HIV

Answer 27

Don’t breast feed
ART within 4 hours of birth
if low-risk of transmission - zidovudine monotherapy for 2-4 weeks
if high risk - triple ART for 4 weeks
Confirm dx of HIV in neonate at birth, on discharge, at 6 weeks and 6 months

Question 28

Antenatal mx of Hep B

Answer 28

refer to hepatologist
offer tenofovir in 3rd trimester and stop 4-12 weeks after delivery
monitor LFTS every 2 months

Question 29

Postnatal mx of Hep B

Answer 29

Hep B Ig (within 24 hours) and Hep immunisations

Question 30

Mx of Hep c

Answer 30

Refer to hepatology

NB - usual treatments (interferon and ribavirin) are contraindicated in pregnancy and should be started postnatally