Infections of Pregnancy Flashcards
What are the consequences of infection for the embryo and fetus?
Spontaneous abortion
Preterm Birth
IUGR
Congenital abnormality
Neonatal morbidity and mortality
IUGR stands for intrauterine growth restriction.
What are some ultrasound features indicating fetal infection?
Ventriculomegaly
Hepatosplenomegaly
Placentomegaly
Hydranencephaly
Microcephaly
Intracranial calcifications
Cardiac anomalies
Echogenic bowel
Intrabdominal calcification
Hydrops
IUGR
Abnormal AFV
AFV refers to amniotic fluid volume.
What are the methods of infection transmission to the fetus?
Hematogenous spread to fetus and placenta,
Cross placental barrier directly
Transmission depends on agent, severity of infection, maternal immune status, and gestational age of fetus.
What factors are involved in diagnosing maternal infection?
Maternal History,
Lifestyle,
Clinical symptoms,
Contacts,
Geography,
Maternal serology,
Fetus: AF culture, EM, PCR, PUBS, Anemia, abnormal WBC and platelets, abnormal LFTs
LFTs refer to liver function tests.
What are the characteristics of congenital CMV infection?
HD-PIMP
Hepatosplenomegaly
DIC
-
PTB
Intracranial calcifications
Microcephaly
Petechiae
DIC refers to disseminated intravascular coagulation.
What is the significance of IgM in diagnosing maternal CMV infection?
IgM appears early in disease course and persists for 4-8 months, but is not present in reactivation.
Radioimmunoassay is the most reliable test in pregnancy for acute primary infections.
What is Toxoplasmosis and its primary transmission routes?
Toxoplasma gondii, primarily transmitted through raw/undercooked meats, cat feces, or contaminated soil
It is associated with immunosuppression and is a leading cause of foodborne illness.
What is the triad of congenital Toxoplasmosis?
Chorioretinitis, Intracranial calcifications, Hydrocephalus
Most infected individuals may show no obvious clinical signs but can develop disabilities later.
What are the ultrasound features of congenital Varicella syndrome? (‘‘PHILMS’’)
Polyhydramnios
Hydrops
IUGR
Limb contractures / hypoplasia
Multiple hyperechoic foci in liver
Small eyes, limb, head
Varicella can cause significant fetal abnormalities if infection occurs before 20 weeks gestation.
What is the clinical significance of Rubella in pregnancy?
Highly teratogenic, with 100% infection rate with CRS if infection occurs within 3-6 weeks of LMP
CRS stands for congenital rubella syndrome.
What is the ultrasound triad associated with congenital syphilis?
Hepatomegaly,
Placentomegaly,
Non-immune hydrops
Treponema pallidum is the causative agent of syphilis.
What factors increase the risk of neonatal herpes transmission?
Subclinical shedding,
Scalp electrodes,
AROM,
Instrumental delivery
C/S (cesarean section) is protective against transmission during active lesions.
How to prevent herpes transmission to baby?
C/S
What information should the mother know about HSV-1?
- Cover cold sores
- Breastfeed provided there are no active lesions on breast
- It’s less likely to cause encephalitis and neurodevelopmental problems.
What is the recommended treatment for a pregnant woman exposed to Varicella?
- Check bloods: If IgG negative, give VZIG within 10 days post exposure prophylaxis to reduce risk of varicella pneumonitis. If IgG positive, do nothing.
- If symptomatic, treat with acyclovir
VZIG stands for Varicella Zoster Immunoglobulin.
What is the significance of Zidovudine (AZT) in HIV-positive pregnant women?
66% reduction in maternal-fetal transmission of HIV when administered
IV Zidovudine is given during labor if viral load is >1000.
What is the risk of parvovirus?
It attacks fetal bone marrow, causing anemia
Hydrops
IUFD
What may give an indication of parvovirus infection?
Transient ascites and meconium peritonitis
What antibodies are important in parvovirus?
IgM - Present after 3 days but absent in 1-2 months
IgG - Persist forever
IgG +ve but IgM -ve = Previous infection
How to diagnose parvovirus in pregnancy?
PCR amniotic fluid, chorionic villi, fetal blood
24 week pregnant woman has a 4 year old son with slapped cheek syndrome, what should you do?
A: Call lab and run parvo screen on her booking bloods
If IgG +ve - do nothing
IgG -ive - Check for IgM
IgG +ve - 33% chance of transplacental trasnmission
