Effects of Infection in Early Pregnancy Flashcards
Why are pregnant women more at risk of infection
- pregnancy is an immunosuppressive state
- physiological changes to the mothers body
describe why pregnant women are more at risk of infection
- Relative immune-suppression – pregnancy is relatively immunosuppressed state, certain conditions are for some reason a lot worse in pregnancy than others for example Hep E this carries a 25-30% mortality risk, this is significant in the regions of the word where this happens
- Physiological changes in mother - pregnant women who get influenza have a worse outcome than non-pregnant women, this is not an immunological reason but is because of anatomy reasons this puts pressure of the diagram and reduces the overall expansion of the lungs therefore this reduces the spread
What infections are
- harmful to the mother
- harmful to the foetus
- harmful to both
Harmful to the mother
- Influenzas
harmful to the foetus
- Toxoplasmosis
- HSV
- Syphilis
- Parvovirus B19
- CMV
- Rubella
Harmful to both
- VZV
- HIV
- Hepatitis A/E/B/C
What does TORCHES stand for
Toxoplasmosis Other Rubella Cytomegalovirus (CMV) Hepres Simple virus
What is toxoplasmosis
a disease that results from infection with the Toxoplasma gondii parasite,
How do we diagnose infection in pregnancy
Serology and PCR
what do you look at in serology
- Look at IgM and IgG
what is the difference between IgM and IgG
- IgM is the antibody that goes up in an acute infection and then goes down
- IgG is a memory antibody so evidence of IgG signifies a past infection and is protective in many cases
what happens at 10 weeks
- all serologies get tested
- therefore you have a baseline at that moment in time as to what infections you have previously had
- have blood tests to compare it to if you become infected later
how do you use PCR
- DNA and RNA is present in viruses
- Can find a bit of DNA or RNA you can amplify it and match it against the database and diagnose it
how common is CMV
- VERY COMMON
- 50% OF UK adults
What type of virus is CMV
Herpes virdae virus
What does CMV stand for
Cytomegalovirus
describe how CMV can cause flairs
A flair is a reactivation of CMV can happen at points of stress or at any time in your life
- if it happens during pregnancy it will spread to the baby and cause problems
what vaccine is used to prevent chicken pox
VZV vaccine
How does the transmission of CMV happen
via saliva, blood or blood products, sexual intercourse, organ transplantation or via mother
what is a primary infection of CMV likely to cause
congenial CMV - this is because the viral load is higher therefore the chance of transferring the virus to the foetus
- more likely to happen in the 1st trimester of pregnancy
What is the prevalence of congenital CMV
~ 7 per 1000 live births (0.7%)
• only 13% of babies with congenital CMV are symptomatic
How do you diagnose CMV
- maternal serology CMV IgG and IgM
- neonatal urine/saliva for CMV DNA PCR test and look directly for the virus
- blood, saliva and urine
What are the symptoms of CMV
- severe: Intra Uterine Growth Retardation (IUGR), hepatosplenomegaly, microcephaly
- sensorineural deafness
What is the main symptom affect of CMV
sensorineural deafness
why do you not do a serology test on babies in the first 6 months of life and while they are breastfeeding
because they do not have their own antibodies
what is the commonest cause of congenital sensorineural hearing loss
CMV
What is the heel prick test
- Can be stored for life
- used to mark specific disease
disease
- sickle cell disease
- cystic fibrosis
- congenital hypothyroidism
- PKU
- MCADD
- MSUD
