9- Medical problems in pregnancy (systemic and blood borne infections) Flashcards
rubella is also known as
german measles
Congenital rubella syndrome
is caused by maternal infection with the rubella virus during the first 20 weeks of pregnancy. The risk is highest before ten weeks gestation.
- sensorineural deafness
- congenital cataracts
- congenital heart disease
- growth retardation
- hepatosplenomegaly
- cerebral palsy
why has incidence of rubella dropped
MMR vaccine
when should a women be screened for rubella immunity
if she hasnt had the vaccine or is unsure
antenatal screening for rubella
Two tests were performed:
- IgM antibody – present in acute infection.
- IgG antibody – present following infection or vaccination.
In cases where neither antibody was present, the woman was encouraged to seek rubella vaccination post-delivery (rubella vaccine is a live virus, and should not be administered whilst pregnant).
presentation of maternal rubella
often asymptomatic
non-specific
- malaise
- headache
- coryza
- lymphadenopathy
- fine maculopapular rash
investigations for maternal rubella
In women where rubella infection is suspected, ELISA can be performed to measure rubella specific IgG and IgM:
- IgM antibody – present in acute infection.
- IgG antibody – present following infection or vaccination.
management for a pregnant women with a positive rubella screen
should be immediately referred to a fetal medicine specialist for counselling and further management.
maternal rubella: maternal management
No treatment- self-limiting
- antipyretics
- she should be informed that she is infective from 7 days prior to onset of symptoms and to 4 days after
maternal rubella: fetal management
Congenital rubella syndrome much more likely to occur if contracted <12 weeks
- gestation of infection determines management
management of maternal rubella in pregnancy <12 weeks
high likelihood of defects, it is reasonable to consider a termination of the pregnancy.
management of maternal rubella in pregnancy <12 weeks
high likelihood of defects, it is reasonable to consider a termination of the pregnancy.
management of maternal rubella in pregnancy 12-20 weeks
prenatal diagnosis of fetal rubella infection required. This is usually performed by RT-PCR on amniotic fluid samples.
- If transmission to the fetus is confirmed, management options include termination of pregnancy or ultrasound surveillance to identify features of congenital rubella syndrome (although some features of CRS cannot be detected by ultrasound).
management of maternal rubella in pregnancy >20 weeks
No action required.
congenital rubella syndrome classifcal features can be split into
‘present at birth’ and ‘late onset’.
CRS: present at birth
- Auditory Problems
o Sensorineural deafness - Cardiac Defects
o Pulmonary Stenosis, Patent Ductus Arteriosus, Ventricular Septal Defect - Ophthalmic Defects
o Retinopathy, Congenital Cataracts - Central Nervous System Abnormalities
o Learning disabilities, Microencephaly
CRS: late onset symptoms
- Diabetes mellitus
- Thyroiditis
- Growth Hormone Abnormalities
- Behavioural Disorders
Varicella zoster is a DNA virus responsible for:
- Chickenpox (also known as varicella) – a result of primary infection.
- Shingles (also known as herpes zoster) – a result of viral reactivation.
varicella in pregnancy
- rate due to high levels of immunity in pop
- causes mild illness in children, however if contracted in pregnancy there is increased morbidity and mortality for both mother and foetus
primary varicella zoster presentation
- fever
- malaise
- pruritic maculopaular rash (becomes vesicular and crusts before healing)
- 10-21 day incubation period
- women infectious from 48 hours prior to rash until vesicles have crusted
which complications of varicella zoster infection accounts for the 2% mortality in mothers
pneumonitis , hepatitis, and encephalitis
diagnosis of varicella zoster
clinical diagnosis. if in doubt 2 main investigations:
* Immunofluorescence of basal epithelial cells scrapped from vesicle.
* PCR for varicella zoster DNA.
how to test immunity for varicella zoster
To determine immunity status, women can be tested for IgM and IgG antibodies to varicella zoster. If present, they indicate the woman has immunity against the virus (usually from previous infection or vaccination).
management of varicella zoster: 2 scenarios
1) Women has encountered soemone infectious with varicella zoster
2) women with confirmed varicella zoster
Management: Women has encountered someone infectious with varicella zoster
Determine immunity:
1) Patient describes previous infection: assume immunity and no further action required
2) Patient has no previous infection
- do IgG testing to confirm immunity status
- if <20 week give women varicella zoster immunoglobulin (VZIG) within 10 days of the contact and before the onset of rash
- if >20 weeks then women can receive either VZIG or aciclovir from 7 to 14 days following exposure
management of confirmed maternal chickenpox
Aciclovir (800mg PO 5tds) should be prescribed in patients presenting within 24 hours of rash onset and at >20 weeks gestation. Consider aciclovir prescription in mothers <20 weeks.
The mother should be counselled about the symptoms of pneumonia, neurological signs and haematological rash – and instructed to attend hospital immediately should they occur.
In addition, she should be referred to a fetal medicine specialist, with serial ultrasound examinations beginning at 5 weeks post infection to identify any fetal abnormalities.
Varicella Vaccination
If a woman is found to be seronegative for varicella zoster IgG, pre-pregnancy or postpartum vaccination should be considered. Vaccination is not recommended during pregnancy as a matter of caution.
complications of varicella zoster infections
1) Varicella of the newborn
2) Fetal varicella syndrome
1) Varicella of the newborn
If maternal chickenpox occurs within the last 4 weeks of the pregnancy, there is significant risk (50%) of varicella infection of the newborn. This can be asymptomatic.
The route of infection can be:
- Transplacental
- Vaginal
- Direct contact after birth
ManagementVaricella of the newborn is treated with varicella-zoster immunoglobulin (VZIG) ± aciclovir.
2) Fetal varicella syndrome
is caused by subsequent reactivation of the virus in utero as herpes zoster. This reactivation only occurs when the fetus is infected by maternal varicella before 20 weeks gestation.
Fetal varicella syndrome presentation
1) Skin scarring in a dermatomal distribution
2) Eye defects
- Microphthalmia
- Choriorenitis
- Cataracts
- Optic atrophy
3) Hypoplasia of the limbs
4) Neurological Abnormalities
- Microcephaly
- Cortical and spinal cord atrophy
- Seizures
- Horner’s Syndrome
Cytomegalovirus is a member of the
herpesvirus family
- most common virus transmitted to the fetus during pregnancy
how many women become infected with cytomegalovirus during pregnancy
Approximately 1 in 100 women become infected with cytomegalovirus during pregnancy (although most remain asymptomatic). Around one third of maternal CMV infections are then vertically transmitted to the fetus.
cytomegalovirus presentation
Cytomegalovirus infection is usually asymptomatic in immunocompetent individuals.
It can occasionally produce a mild flu-like illness. Alternatively, in some patients, it can cause a mononucleosis syndrome (similar to Epstein-Barr); resulting in fever, splenomegaly and impaired liver function.
investigations for CMV
If maternal cytomegalovirus infection is suspected, viral serology for CMV specific IgM and IgG is performed.
A positive test is signified if:
- Presence of CMV specific IgG in mother previously seronegative (i.e. seroconversion has occurred).
- Presence of CMV IgM and low IgG avidity (<30%).
- Note: Avidity refers to the strength with which the antibody binds to the antigen.
maternal management of CMV
In an immunocompetent woman, no treatment of the infection is required.
The licensed anti-CMV drugs (ganciclovir, cidofovir and foscarnet) have potential teratogenic effects and a well-known toxicity profile (haematological and renal), and thus are not recommended for use in pregnancy.
fetal management for CMV
- diagnosed prenatally via amniocentests and PCR of resulting amniotic sample (must be after 21 weeks gestation because functioning fetal kidneys are required for virus to be excreted into amniotic fluid)
- no effective therapy, termination can be offered
- if women wants to continue pregnancy serial US can be offfered to assess for manifestations of congenital CMV
presentation of congenital cytomegalovirus
Neonates born following an intrauterine CMV infection can have several problems:
- Intrauterine growth restriction
- Hepatosplenomegaly
- Thrombocytopaenic purpura
- Jaundice
- Microencephaly
- Chorioretinitis
There is 20-30% mortality in this symptomatic group. This is often due to disseminated intravascular coagulation (DIC), hepatic dysfunction and/or bacterial superinfection.
Babies born without symptoms of CMV infection have a 10-15% chance of developing sequelae of the infection within 2 years. This may include:
* Sensorineural hearing loss
* Psychomotor development delay
* Visual impairment
parvovirus B19
is a single stranded DNA virus, which is transmitted by respiratory droplets or blood.
parvovirus B19 in adults vs fetus
The virus produces a mild, self-limiting infection in adults, but can cause spontaneous miscarriage or intrauterine death if transmitted to the fetus during pregnancy.
- vertical transmission
presentation of parvovirus in adults
mostly asymptomatic
The most common clinical feature is symmetrical arthralgia – typically of the proximal interphalangeal joints and/or knees.
presentation of parvovirus in children
- Upper respiratory tract infection
- Malaise
- Headaches
- Low-grade fever.
- Erythema infectiosum (slapped cheek syndrome) – a maculopapular rash sparing the nose, eyes and mouth.
investigations for slapped cheek
In cases where a mother has potentially come into contact with parvovirus B19, viral serology can be performed:
- Parvovirus specific IgM antibodies indicate recent infection
- Parvovirus specific IgG antibodies indicate past infection and therefore immunity.
maternal management of parvovirus
Parvovirus infection is self-limiting, and does not require treatment. Antipyretics and analgesia can be given.
- should be reffered to fetal medicine specialist
The main risk of fetal parvovirus infection is
fetal hydrops
management of fetal parvovirus
1) Serial ultrasound scans and Doppler assessment
- Starting 4 weeks post infection or at 16 weeks.
- Repeated every 1-2 weeks, until 30 weeks gestation.
2) If there is evidence of fetal hydrops on ultrasound, the patient should be referred to tertiary centre for intrauterine erythrocyte transfusion.
fetal hydrops
the abnormal accumulation of fluid in two or more fetal compartments
Pathophysiology
Fetal hydrops occurs because parvovirus B19 has an affinity for the erythroid system and replicates within the erythroid progenitor cells of the liver and bone marrow. This induces severe anaemia which results in:
- High output cardiac failure
- Increased extrahepatic and hepatic erythropoiesis – resulting in portal hypertension and hypoproteinaemia with subsequent ascites.**
Diagnosis
It is diagnosed by ultrasound scan with features including: ascites, subcutaneous oedema, pleural effusion, pericardial effusion, scalp oedema and polyhydramnios.
zika virus is spread by host …… ……. in areas of the world where the virus is prevalent.
Aedes mosquitos
how can zika virus also be spread
sex
presentation of zika virus
Can be asymptomatic
- acute onset of fever with maculopapular rash
- arthralgia
- conjunctivitis.
- Other commonly reported symptoms include myalgia and headache.
zika virus can lead to
congenital zika syndrome
congenital Zika syndrome presentation
- Microcephaly
- Fetal growth restriction
- Other intracranial abnormalities, such as ventriculomegaly and cerebellar atrophy
Microcephaly
is a condition where a baby’s head is much smaller than expected. During pregnancy, a baby’s head grows because the baby’s brain grows. Microcephaly can occur because a baby’s brain has not developed properly during pregnancy or has stopped growing after birth, which results in a smaller head size.
investigations for zika virus
Pregnant women that may have contracted the Zika virus should be tested with viral PCR and antibodies to the Zika virus.
management of maternal zika virus
Women with a positive result should be referred to fetal medicine for close monitoring of the pregnancy. There is no treatment for the virus.
ways in which HIV can be transmitted
- Unprotected anal, vaginal or oral sexual activity
- Mother to child at any stage of pregnancy, birth or breastfeeding (called vertical transmission)
- Mucous membrane, blood or open wound exposure to infected blood or bodily fluids, for example, through sharing needles, needle-stick injuries or blood splashed in an eye
what is the risk of vertical transmission if HIV is untreated?
1 in 4
HIV management in the antenatal period
Antenatal antiretroviral therapy during pregnancy and delivery (Zidovudine)
preventing HIV transmission during birth
The mother’s viral load will determine the mode of delivery:
- Normal vaginal delivery is recommended for women with a viral load < 50 copies / ml
- Caesarean section is considered in patients with > 50 copies copies / ml and in all women with > 400 copies / ml
- IV zidovudine should be given during the caesarean if the viral load is unknown or there are > 10000 copies / ml
prophylaxis HIV treatment for infant
- Low-risk babies, where the mother’s viral load is < 50 copies per ml, are given zidovudine for four weeks
- High-risk babies, where the mother’s viral load is > 50 copies / ml, are given zidovudine, lamivudine and nevirapine for four weeks
Breast Feeding and HIV
HIV can be transmitted during breastfeeding, even if the mother’s viral load is undetectable. Breastfeeding is not recommended for mothers with HIV. However, if the mother is adamant and the viral load is undetectable, sometimes it is attempted with close monitoring by the HIV team.
influenza and pregnancy
- more dangerous during pregnancy and more likely to get seriously ill
- can cause premature delivery
prevention of influenza during pregnancy
flu vaccine- any time during pregnancy
syphilis tranmission
- Oral, vaginal or anal sex involving direct contact with an infected area
- Vertical transmission from mother to baby during pregnancy
- Intravenous drug use
- Blood transfusions and other transplants (although this is rare due to screening of blood products)
syphilis and pregnancy
- women offered screening for syphilis at booking
- early treatment of syphilis during pregnancy is importnant since it can cross the placenta and infect baby during delivery
complications of syphilis and pregnancy
miscarriage, stillbirth, pre-term labour or congenital syphilis.
presentation of congenital syphilis
- saddle nose
- rashes
- fever
- failure to weight gain
management of maternal syphilis infection
- referreal to GU doctor asap
- single dose of benzathine penicillin
Covid-19 and pregnancy
higher risk of getting seriously ill esp if >28 weeks
Other things that can put you at higher risk if you are pregnant include if you:
* have an underlying medical condition (such as diabetes, high blood pressure, heart disease or asthma)
* are overweight
* are aged 35 or over
* are from an ethnic minority group
complications of covid-19 during pregnancy
- premature birth
- low birthweight
- stillbirth
complications of covid-19 during pregnancy
- premature birth
- low birthweight
- stillbirth
There’s no evidence COVID-19 causes
miscarriage or affects how your baby develops in pregnancy.
how to reduce risk of covid-19 during pregnancy
covid-19 vaccine
