perinatal infection Flashcards
What are clinical features of congenital rubella syndrome
Sensorineuronal deafness catarcts blindness endocrine problems encephalitis
Infection risk of rubella in pregnacy
<11 weeks - 100% chance of transmission
>20 weeks no risk
How to detect syphilis
Treponema antibodies (EIA)
Mx of prenatal syphilis
contact sexual health clinic for track and trace
IM benzyl penicillin
beware of Jarish-Herxheimer reaction
How to diagnose toxoplasma gondii
Sabin feldman dye test
Or after abnormal US do amniocentesis and PCR
Features of foetal CMV infection
Growth restriction
microcephaly
intracranial calcification
Hydrops
can also cause anaemia, splenomegaly, hepatomegaly
Diagnosis of CMV
Need to have a positive finding of CMV Ab in a lady who was previously negative
If foetal infection suspected do amniocentesis and PCR
Prevention of VZV transmission in pregnancy
if negative avoid contact during pregnancy
Mx if VZV -ve comes into contact with +ve
How long are they considered infectious for?
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
Mx of chicken pox in pregnancy
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
Diagnosis of congential varidella syndrome
(RARE) at least one of: scarring in dermatomal distribution limb hypoplasia Eye defects neuro defects
No cases reported if infection happens after 28 weeks
Mx of VZV at delivery
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
Complications of congenital parvovirus
Child becomes anaemic, get high output cardiac failure and liver congestion –> hydrops
Mx of parvovirus
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)
What raises suspicion of listeria
meconium staining
Mx of listeria
IV amoxicillin for 2 weeks
Advice about prevention
Why can malaria be missed antenatally
Can sequestrate blood in placenta
What are the three subgroups of neonatal herpes
(can be caused by HSV1+2)
- localised to eyes and mouth
- localised to CNS only
- disseminate inter organ failure
When is the greatest risk with HSV
Contracting primary infetion
especiallly if within 6 weeks of delivery
Mx of first episode HSV
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
Mx of recurrent episode of HSV
What notes do you have to make for delivery?
daily suppressive aciclovir from 36 weeks
offer vaginal delivery
avoid ARM + invasive procedures during labour
RF for requiring GBS prophylaxis
Intrapartum fever Prolonged rupture of membrane (18 hours) <37 weeks Hx of infant w/ GBS detection of GBS on swab or GBS bacteriuria
Mx GBS
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
When does HIV transmission usually occur
Late 3rd trimester
Delivery
When breastfeeding
Antenatal mx of maternal HIV
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
Intrapartum mx of HIV
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
Postnatal mx of HIV
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
Antenatal mx of Hep B
refer to hepatologist
offer tenofovir in 3rd trimester and stop 4-12 weeks after delivery
monitor LFTS every 2 months
Postnatal mx of Hep B
Hep B Ig (within 24 hours) and Hep immunisations
Mx of Hep c
Refer to hepatology
NB - usual treatments (interferon and ribavirin) are contraindicated in pregnancy and should be started postnatally
