Infections in Pregnancy Flashcards
Rubella incubation
12-23 days
What type of organism is Rubella
RNA togavirus
Risk of fetal infection with Rubella
<11 = >90%
11-16/40 = 20%
>20/40 = 0%
Rubella vaccination
Live vaccine
Congenital rubella syndrome features
Sensorineural deafness, cataracts and cardiac anomalies
What type of organism is Measles
single stranded enveloped RNA
Measles incubation and infectious periods
Incubation = 10-12 days, rash 14 days post exposure
Infectious = 4 days pre until 4 days post rash
Fetal complications of measles
No increased congenital abnormalities
increased IUGR, NICU adm, IUD
What type of organism is Parvovirus B19
dsDNA virus
Incubation period of Parvovirus
4-14 days (7 average)
Infectious period of Parvovirus
7-10 days pre rash
Test for recent parvovirus infection
IgM - if positive, suggests recent infection
IgG +ve = immune
Fetal risks of parvovirus
hydrops, anaemia, heart failure
Death = 1-4%
Risk of parvovirus vertical transmission
<15 weeks gestation - 15%
15 - 20 weeks - 25%
Term - 70%
What type of organism is VZV
DNa virus
VZV incubation period
10-21 days
Incidence of VZV in pregnancy
3 in 1000
Maternal complications of VZV in pregnancy
Pneumonia (10%)
Hepatitis
Encephalitis
Risk of fetal varicella syndrome
Signs
1% if <28/40
0% if >28/40
Skin scarring, eye defects, limb hypoplasia, developmental delay
Timing of scan following VZV infection in pregnancy
16-20/40 or 5 weeks post infection
Management of vzv exposure
Check VZV Ig
- +ve –> reassure
- -ve –> <10 days from exposure –> VZIG and inform infections 8-28 days
Treatment of VZV in pregnancy
> 20/40 and <24 hours from rash = aciclovir 800mg 5x/day for 7 days
Severe infection = IV aciclovir
Risk of neonatal VZV infection
If birth within 1-4 weeks –> 50% infected and 23% these have clinical varicella
Birth within 7 days –>give VZIG
CMV incubation period
3-12 weeks
Risk of congenital CMV
Primary infection = 20-30%
Recurrent infection = 1-2%
Percentage of pregnant women CMV sero+ve
50%
Percentage of pregnant women who will have primary CMV infection in pregnancy
2%
Risk of symptoms following congenital CMV
What are the symptoms
10-15% symptoms at birth
10-15% develop symptoms at later life
Sensorineural deafness, microcephaly, visual impairment, IUGR, CP
Mortality with neonatal CMV
% of survivors with sequelae
20-30%
90% survivors have sequelae
Timing of amniocentesis for CMV
6 weeks post infection and after 21/40
Incubation of toxoplasmosis
5-23 days
Fetal risks of toxoplasmosis
%
Features
60% no effect
10% chorioretinitis
20-30% TORCH anomalise
Spontaneous first trimester miscarriage, Chorioretinitis, IUGR
Microcephaly, Hydrocephalus, Intra-cranial calcification
Learning disability, Hepatosplenomegaly
Investigation for toxoplasmosis
IgM+ve
Then 2nd sample 3 weeks later
- high IgM
Or - IgG 4fold rise
Treatment for toxoplasmosis
Spiromycin –> 60% reduction in fetal risk
If fetus infection –> pyrimethamine + sulfonamide + folinic acid (slows fetal disease)
Treatment of chlamydia in pregnancy
Amoxicillin
Erythromycin
Azithromycin
What kind of virus is HSV
DNA virus
Risk of neonatal transmission with:
Primary infection
reccurent infection
41%
0-3%
Whats the proportion of HSV cases in neonate due to HSV 1 vs HSV 2
50% each
HSV infection treatment
<28/40
>28/40
Recurrent
In HIV
- 5/7 aciclovir 400mg TDS then from 36/40
- Aciclovir 400mg TDS until birth, CS if primary
- Usually self limiting, consider aciclovir from 36/40
- Aciclovir from 32/40
Treatment of malaria
Simple = quinine 600mg TDS for 5-7 days or clindamycin 450mg TDS for 5-7 days then mefloquine for 7 days
Severe:
Uncomplicated = IV quinine
Complicated = IV artenusate
Non faciparum = chloroquine
How long should you not get pregnant after exposure to Zika virus?
3 months from last exposure if both partners/only male exposed
2 months if only woman
What fetal impact does Zika have
Microcephaly
What ARVs should you start newly dx HIV on?
tenofovir or abacavir or lamivudine
PLUS efavirenz or atazanavir / ritonavir
If v high VL, include raltegravir or dolutegravir
Which ARV is associated with increased neural tube defects
Dolutegravir - give 5mg folic acid
Neonatal management of HIV
Very Low risk
Low risk
High risk
Very low risk = 2 weeks zidovudine
- On cART >10/52 + 2xVL<50 4 weeks apart + 36/40 VL <50
Low risk = 4 weeks zidovudine
High risk = neonatal PEP
Infant testing for HIV
Not breastfeeding = within 48hrs, at 6 weeks and 12 weeks
Breastfeeding = within 48hrs, at 2 weeks, monthly whilst BF and 4 + 8 weeks post stopping BF
When do you start cART for HIV in pregnancy
by 24/40 for everyone
VL <30,000 = when can in T2
VL 30-100,000 = start of T2
VL >100,000 or CD4<200 = ASAP, can start T1
What are examples of a-haemolytic strep?
How to differentiate between?
S viridans
S pneumoniae
Optochin disc test
How do you differentiate between alpha and beta haemolytic strep
a = green colour around colony
b = complete lysis of red cells
Grouping of B-haemolytic strep?
Lancefield grouping = based on carbohydrate composition of cell walls
Rate of GBS colonisation
20-40%
Rate of EOGBS
0.57 per 1000 births
Risk of EOGBS
General pop
Previous GBS
Preterm
Temp in labour
General pop = 0.6 in 1000
Previous GBS = 1.25 in 1000
Preterm = 2.3 in 1000
Temp in labour = 5 in 1000
Risk of death and disability with EOGBS
Death = 5.2%
Disability = 7.5%
Risk factors of EOGBS
Previous baby with GBS
GBS bacturia
+ve GBS swab in pregnancy
Maternal temp in labour
GBS abx if pen allergic
Cefuroxime 1.5g loading then 750mg 8hrly
OR
vancomycin 1g 12hrly
Neonatal tx of suspected GBS
Penicillin + gentamicin
Maternal mortality of COVID
2.4 per 100,000 maternities
Treatment of MRSA colonisation
Mupirocin ointment TDS for 5 days
Treatment of MRSA infection
Vancomycin or teicoplanin
Linezolid if resistant to above
Treatment of sepsis in pregnancy
Not critically ill:
Co-amox + metro
Cefuroxime 1.5g 8hrly + metro
Cefotaxime 1-2g 6-12hrly + metro
Clarithro/clinda + gent +/- metro
Severe sepsis:
tazocin + gent
meropenem + gent
Treatment of group A strep
Clindamycin
Sepsis bundles to be completed within:
3 hours
6 hours
3 hours:
Sepsis 6 - lactate, blood cultures, IV abx, O2 (sat >94%), urine output, give 30ml/kg crystalloid
6 hours:
- recheck lactate if raised
- vasopressors if needed to maintain MAP >65
Most common postpartum infection
Endometritis
Rate of false positive and negative tests in syphilis
1% (VDRL and Abs)
In preterm labour, what drug do you give to help load baby in HIV
Double dose tenofovir
How long should you wait post Zika for fertility treatment?
Exposure?
Infection?
Exposure = 28 days
Infection = 6 months, test semen for Zika on RT-PCR
Risk of fetal transmission of toxoplasmosis
<4 weeks: <1%
13/40: 10%
>36/40: 60%