infections in pregnancy Flashcards
what % of people in the UK are immune to chicken pox
> 90%
how is chicken pox spread
respiratory droplets
symptoms of chicken pox
fever
malaise
itchy vesicular rash
period of infectivity in chicken pox
48h before rash develops to once lesions have crusted over (usually 5-7 days after rash starts)
how serious is chicken pox
usually harmless and self-limiting in children
higher morbidity in adults - hepatitis, pneumonitis, encephalitis
- especially pronounced risk w/ immunocompromised and pregnant women
how common is chicken pox in pregnancy
complicated 3/1000 pregnancies
important to ask women about chicken pox hx at booking appointment
if no hx - avoid exposure to anyone w/ chicken pox/shingles during pregnancy
what is the risk of congenital infection with chicken pox
small risk of congenital infection if maternal infection in first 28wks of pregnancy
what is fetal varicella syndrome
occurs in 2% of case of maternal 1y chicken pox
skin scarring congenital eye abnormalities hypoplasia of ipsilateral limbs neurological abnormalities no increased risk of miscarriage if chicken pox occurs in 1st trimester
maternal chicken pox infection in last 4 weeks of pregnancy
risk of infection in newborn
what to do if a pregnant women, who is unsure if she is immune, is exposed to chicken pox
check immunity status by taking serum IgG
if immune (IgG +ve) - reassure if non-immune (IgG -ve) - offer VZ immunoglobulin ASAP
disadvantages of VZ Ig
still a small risk of contracting chicken pox
no therapeutic benefit once chicken pox has already developed
what to do with a pregnant woman who develops chicken pox rash
inform GP
avoid contact w/ susceptible individuals - other pregnant women, neonates - until lesions crusted over
management of mild chicken pox infection
mild infection, if presents within 24hrs from onset of rash:
>20wks - oral aciclovir, also consider if <20wks
symptomatic treatment and hygiene to prevent 2y bacterial infection
mild infection, if presents >24hrs from onset of rash: symptomatic treatment, hygiene to prevent 2y bacterial infection
severe infection: admit to hospital, IV aciclovir
what causes shingles
herpes zoster
reactivation of chicken pox virus which has remained dormant in the sensory nerve root ganglion since 1y infection
can you catch chicken pox from someone with shingles
yes but it is rare
parvovirus B19 is aka
slapped cheek disease
fifth disease
erythema infectiosum
what % of women are immune to parvovirus B19
~50%
how severe is parvovirus B19
common and mild febrile illness of childhood
adults may be susceptible if never exposed
immunocompromised pts - can cause aplastic anaemia and haemolysis
how is parvovirus B19 spread
respiratory secretions
symptoms of parvovirus B19
fever
rash
erythema of cheeks
most adults are asymptomatic
treatment for parvovirus B19
no vaccine or treatment available
parvovirus B19 infection during pregnancy
can lead to fetal anaemia –> cardiac failure, hydrops fetalis and fetal death
rarely causes pre-eclamptic condition in the mother w/ significant oedema
when is the most critical exposure period to parvovirus B19 during pregnancy
12-20wks
fetal infection usually occurs 5wks after maternal infection
what to do with a pregnant woman w/ possible parvovirus B19 exposure and possible illness
bloods - Ig testing
if +ve - offer weekly scans to monitor for fetal complications
what causes toxoplasmosis
how common is it
protozoa - toxoplasma gondii
2/1000 pregnancies
how is toxoplasmosis transmitted
through cat faeces and undercooked meats by directly ingesting the parasite
what % of women are immune
~20%
symptoms of toxoplasmosis
asymptomatic
OR
mild flu like symptoms - fever, sore throat, coryza, arthralgia
serious complications of toxoplasmosis
rare
chorioretinitis
encephalitis
myocarditis
pneumonitis
how long does it take for parasitaemia to occur in toxoplasmosis
occurs within 3wks of ingestion
advice for pregnant women re. toxoplasmosis
avoid cleaning cat litter trays and eating undercooked meat
when can placental infection occur with toxoplasmosis
placental infection is possible both during pregnancy and immediately prior to pregnancy
possible fetal complications from toxoplasmosis
hydrocephalus intracranial calcifications microcephaly chorioretinitis ventriculomegaly IUGR ascites hepato-splenomegaly
miscarriage and IU death
infection in the 3rd trimester puts the fetus most at risk
how to confirm congenital toxoplasmosis infection
PCR analysis of amniotic fluid obtained from amniocentesis can identify toxoplasmosis and may confirm congenital infection
HIV risks if pregnant women if infected
no increased risk of congenital abnormalities
increased risk of pre-eclampsia, miscarriage, pre-term delivery and low birth weight
what investigations are offered to pregnant women w/ HIV
weekly scans to monitor fetal growth
what happens to babies born to HIV +ve mother
should be referred to neonatology
offered HIV testing
MDT input for HIV +ve mothers
obstetric consultant team community midwifery team HIV specialist neonatologist GP
aims of combined anti-retroviral treatment (cART)
- viral load <50 HIV RNA copies/ml - allows vaginal delivery
- reduce risk of vertical transmission
- improve mother’s health
all women are recommended to continue anti-retroviral treatment post-natally
what can also increase the risk of vertical HIV transmission
breastfeeding
viral load and associated recommendation
<50 - vaginal birth should be supported
50-399 - pre-labour CS considered between 38-39wks
≥400 - pre-labour CS recommended between 38-39wks
what antitretroviral therapy can also be offered
sometimes intrapartum antiretroviral infusions are also recommeneded
Hep B spread
vertical transmission
bloods and bodily fluids
1/1000 affected in UK
acute hep B infection during pregnancy
majority of babies born will contract hep B at birth and are at risk of later cirrhosis and hepatocellular cancer
chronic hep B with a high viral load - therapy
these women should be offered tenofovir monotherapy in 3rd trimester to reduce risk of transmission to baby
can pregnant women be given the hep B vaccine
yes as it is inactivated
given to women at high risk - IVDU, partner is IVDU/HBV/HIV
is vaginal birth safe if mother is chronic hep B w/ high viral load
yes
which babies are offered hep B Ig
babies whose mother has hep B
also advised to have accelerated immunisation schedule
- initial dose of vaccine at birth (within 24hrs of delivery ) - with further doses at 4 + 8wks then 12mths
when is hepatitis tested for in infants
12 mths
identifies any babies where intervention hasn’t been successful and have become chronically infected
when may response to hep B vaccine be lower
pre-term and low birth weight babies
vaccination schedule is the same as with term babies
hep C complications
can lead to severe hepatitis, chronic liver disease and increased risk of liver cancer
incidence of hep C
1-2% pregnant women
most cases associated with prior injecting drug use
what type of virus is hep C
RNA
pregnancy and liver function
pregnancy associated with a decline in liver function in women w/ hep C
how common is vertical transmission fo hep C
1/20 births
higher if woman is co-infected with HIV
indications to offer hep C antenatal screening
all substance misusing pregnant women
any pregnant woman w/:
- prev hx IVDU
- current/previous partner w/ any hx of IVDU
- HIV+ve/hep B +ve
- having hepatitis screen for the indication of deranged LFTs
preventing transmission of hep C from mother to baby
there are currently no preventative means to prevent transmission
is hep C treated in pregnancy
NO
the drugs used are teratogenic and therefore CI
hep C and vaginal birth
vaginal birth and breastfeeding is safe
what causes syphilis
spirochaete - treponema pallidum
spread of syphilis
direct contact w/ skin lesion - most commonly during sexual contact
increasing prevalence in UK
curing penicillin in pregnancy
course of abx
IM penicillin
complications of chronic syphilis i.e. untreated
neurological, cardiac, skeletal and skin abnormalities for adults and babies affected IU
are you protected once you’ve had syphilis once
NO
infection more than once is possible
past infection w/ syphilis doesn’t produce protective antibodies
does pregnancy alter the disease course of syphilis
no
pregnant women who become infected/ become pregnant while infected should be offered prompt treatment
complications of syphilis during pregnancy
miscarriage stillbirth hydrops fetalis growth restriction congenital infection
can cause serious morbidities for the baby
how can syphilis be transmitted to babies of an infected mother
trans-placentally
exposure to infective lesion at time of birth
characteristics of 1y syphilis
painless, local ulcer - chancre
what happens is 1y syphilis is untreated
4-10wks later
symptoms of 2y syphilis may develop
what happens if 2y syphilis is untreated
disease may eventually progress to 3y syphilis
usually takes 20-40yrs
when does congenital syphilis infection present
within the 1st 2yrs of life or later
2/3 of infected neonates will be asymptomatic at birth but will develop symptoms within 5wks
presentation of congenital syphilis
presentation varies
severe multisystem disease can occur
what to do with babies who are at high risk of congenital infection
refer to neonatology urgently
what is late congenital syphilis
occurs in children ≥2y/o who acquire the infection trans-placentally
Hutchinson’s triad
what is Hutchinson’s triad
deafness
interstitial keratitis
Hutchinson’s teeth - widely spaced, peg like
group of symptoms found in late congenital syphilis, occurs in 63% of cases
treatment for late congenital syphilis
penicillin
