Maternal Infections Flashcards
How does rubella present?
Fever, rash, lymphadenopathy, polyarthritis
Transmitted by direct contact/respiratory droplet exposure
What is the rubella triad?
Cataracts
Patent ductus arteriosus
Deafness (due to microcephaly)
Describe the likelihood of rubella complications depending on gestation
<8-10 weeks - 90% chance of multiple defects
11-20 weeks 10-20% chance of single defect
16-20 weeks low chance of deafness
How is rubella in pregnancy managed?
If <12 weeks consider TOP
Specific IgG can be detected after natural infection/vaccination and blood IgM within 10 days of exposure
Supportive treatment - rest, fluids, paracetamol, postnatal vaccination
What causes measles?
Paramyxovirus
How does measles present?
Fever, runny nose, cough, red eyed, rash, Kopek white spots inside mouth, rash appears on forehead first
Is measles teratogenic?
No but the high fever can cause IUGR, microcephaly, miscarriage, stillbirth or preterm labour
What maternal complications can measles cause?
Pneumonia and encephalitis
How is measles managed?
Supportive care to reduce fever
What causes chicken pox and how is it transmitted?
VZV DNA virus of herpes family - transmission is mainly via droplets
How does chicken pox present?
Fever, malaise followed by itch vesicular rash starts on trunk and moves to peripheries
What proportion of people are seropositive for chickenpox by age 10?
9/10
Describe the chicken pox risk depending on gestation
7-28 weeks - fetal varicella syndrome
4 weeks before delivery - neonatal chicken pox
7 days before delivery - neonatal chicken pox with septicaemia
Describe fetal varicella syndrome
Trans-placental infection during pregnancy causes;
- hypoplasia
- psychomotor retardation
- IUGR
- cataracts
- microcephaly
- cutaneous scarring
If a mother has been exposed to chicken pox how can immunity be check and what is done if she is not immune?
IgG antibodies to VZV
VZVIg given within 10 days of exposure
How long is the patient infective with VZV for?
2 days before the symptoms until the lesions crust over
What is classed as significant exposure?
> 15 minutes face to face contact
When should acyclovir be given?
If >20 weeks or <24 hours within rash developing
Name the maternal complications of chicken pox
Hepatitis, encephalitis, pneumonia
What should be done to assess complications post infection?
5 week post infection scan
What type of virus is cyclomegalovirus?
Herpes virus
What are the risks of CMV to the foetus?
Miscarriage, stillbirth, IUGR, microcephaly, intracranial calcifications, hepatosplenomegaly, chorioretinitis, deafness
Is primary or reactivation of CMV more likely to cause congenital infection?
Primary - 30-40%
Reactivation - 1-2%
Which trimester carries higher risk of congenital CMV infection?
3rd trimester
How is CMV diagnosed?
Amniocentesis
IgG in reactivation
IgM with low avidity index
What percentage of asymptomatic CMV babies will go on to have hearing loss?
8-23%
How will CMV present in a baby?
Jaundice, petechial rash, hepatosplenomegaly, microcephaly
What screening is done on babies who’s mums have had CMV?
Ultrasound every 2-4 weeks
Fetal MRI
Fetal blood sample
Post natal examination of placenta
If CMV causes severe cerebral ultrasound abnormalities what may be required?
TOP
How is CMV treated?
Valacyclovir
Hyper immune globulin
What percentage of parvovirus does fetal infection occur?
30%
What is the incubation period of parvovirus?
4-20 days
How long is a person infectious with parvovirus for?
7-10 days prior to rash and 1 day following
When is there a higher risk of fetal loss with parvovirus?
<10 weeks gestation
What does parvovirus do to the foetus?
Affects erythroid precursors - aplastic anaemia, congenital heart failure, hydros and death
How is parvovirus diagnosed?
IgM - serial USS and fetal MCA doppler
Describe mumps in pregnancy
RNA virus no effect on pregnancy, low incidence but MMR vaccine is contraindicated in pregnancy
Is influenza teratogenic?
No but if the infection is virulent there is a risk of miscarriage/preterm labour
What can prevent influenza in pregnancy?
Vaccine - safe in pregnancy and breast feeding
How can influenza in pregnancy be treated?
Antivirals to prevent complications e.g pneumonia
What is zika virus?
Primary infection though mosquito bite can cause serous birth defects
How long does zika virus remain active?
2-7 days most have minimal symptoms
What are the fetal risks of zika virus?
Microcephaly, brain defects, vision and hearing issues, limited joint movement, seizures, swallowing abnormalities, developmental delay
What is the percentage of verticle transmission of HIV?
14-25%
What increases the risk of HIV transmission?
Preterm birth and prolonged rupture of membranes
What are the risks of HIV in pregnancy?
IUGR, miscarriage, perinatal mortality
How are HIV positive pregnant women managed?
Routine screening for HIV, STIs, CMV, TB, toxoplasmosis
Partner screening
Viral load and CD4 count
HAART and prophylactic antibiotics
What can be done to reduce risk of transmission?
Elective c-section (reduces risk by 50%)
Avoidance of breastfeeding (reduces risk by <1%)
ZIidovudine infusion 1 hour before c -section
At what viral load can vaginal delivery be considered?
<50 copies/ml
Define sepsis
Life threatening organ dysfunction caused by the body’s response to infection
What are the signs of sepsis in pregnancy?
RR>22, HR >100bpm, temp>38 or <35, hypotension with systolic <90mmHg, low oxygen and poor peripheral perfusion, clamminess, confusion, rash and mottled skin
How is sepsis managed?
Sepsis 6
Lactate is raised in normal active labour
Where is toxoplasmosis gondii found?
Raw or uncooked meat and infected cat faeces
What are the risks of toxoplasmosis gondii?
Hydrocephalus, choriorentitis, cerebral calcification, microcephaly, mental retardation
How is toxoplasmosis gondii managed?
Spiramycin
What is listeriosis?
Gram positive bacteria found in soil and vegetation - caused by eating infected food or contact with infected miscarried products of animals
How will listeriosis present?
Flu like or food poisoning
What are the complications of listeria?
Neonatal death due to septicaemia, late miscarriage and preterm labour, stillbirth
How is listeriosis treated?
Ampicillin and gentamicin
Trimethoprim and sulfamethoxazole
How can group B strep be treated?
Penicillin
What are the risk factors for GBS?
Preterm birth, prolonged ROM, raised temperature
What is the treatment of UTI in pregnancy?
Nitrofurantoin
Trimethoprim is teratogenic in the first trimester as it inhibits folic acid
