Infectious diseases pregnancy - TORCH Flashcards
What is the incubation of parvovirus? How is it spread?
Respiratory
5-10days
When does the rash appear with parvovirus?
Rash does not occur until 17-18 days after infection and about 5 days after the disappearance of virus from serum and respiratory droplets.
Therefore patients presenting with the clinical features of infection are usually no longer infectious
What % of people are sero+ve?
60%
How do children commonly present with parvovirus?
Erythema infectious/fifths disease ‘slapped-cheek’
Fever, facial rash
How do adults present B19?
Variable
Some asymptomatic
Fever, malaise, arthraligia
Rare - aplastic crisis
Risk of vertical transmission:
<15 weeks
15-20 weeks
Term
Generally
<15: 15%
15-20% - 25%
Term 70%
30%
Risks to pregnancy effected by parvovirus?
Fetal death 5-10% (highest risk 2nd tri)
Nonimmune fetal hydrops - 3% 9-20 weeks
Fetal anaemia
If B19 IgM +ve what does this suggest
Recent infection, will be detect days 3 after symptoms but can remain high for up to 6 months
If negative repeat after 2-3 weeks
If B19 IgG +ve what does this suggest
Immunity, rises on day 7 but remains high for life
IgG and IgM -ve
Susceptible
What other infections should you always test for?
Rubella
If maternal Dx of parvovirus is confirmed, how should the foetus be monitored?
Refer FMU 4 weeks after onset of Sx, for serial USS and doppler
Assessing for anaemia, heart failure and hydros
1-2 weeks MCA and peak systolic velocity
B19 when should cordiocentesis be considered/
If MCA peak systolic resistance is >18
Who is at higher risk of aplastic crisis with B19?
Sickle cell, heredity anaemias (spherocytosis, thalassaemia, pyruvate kinase deficicency ,auto-immune haemolytic anaemia
How Is Rubella spread?
Resp droplet
What % of infected with rubella have symptoms?
What symptoms may there experience?
50-75%
Fever, rash, arthralgia, lymphadenopathy (post-auricular/sub-occiptal)
Describe finding with congenital rubella syndrome?
Eyes - cataracts, retinopathy, glaucoma
Heart - patent ductus/valve stenosis, VSD
Ear - deafness
What is the risk of congenital rubella syndrome? Management?
< 11 weeks
90% - Offer TOP
What is the risk of congenital rubella syndrome? Management?
11-16 weeks
10-20%, deafness common = Amniocentesis
What is the risk of congenital rubella syndrome? Management
> 20 weeks
No babies effected.- NAD
What advice should you give a person who has rubella
Inform PHE (notifiable)
Avoid contact with pregnancy women, stay off work, contact health protection taeam
How is measles spread
Resp illness
What type of pathogen is measles?
Single-stranded, enveloped RNA virus
What is the common presentation of measles?
Prodrome: Fever, malaise, cough, coryza & conjucitivits
3-4 days later
Maculopapular rash, head to truck to lower extremes
Koplik spots - small white lesions on erythematous base.
Incubation of measles?
10-12 days, rash appears 14 days after expose
When is someone with measles infective?
4 days before to 4 days after onset of rash
If susceptible what % of people expose to measles will become infected
90%
Possible compilations of measles to mother?
Pneumonia
Encephalitis
Preg women - high risk morbidity/mortaility
4-10 years later subacute sclerosing pan encephalitis
Management of non-immune pregnant women who are exposed to measles?
IVIG within 6 days of exposure
How should patients with measles be managed?
Supporive, isolated in airborne isolation room.
Impact of measles on foetus?
No increased in congenital abnormalities
Increased risk
- low birth weight
- NICU
- pregnancy loss
- neonatal mortality
When is congenital measles most likely to occur?
Presence of rash at birth or within 1st 10 days of life
Risk mortality and subacute sclerosis panencephlitis
What is the most common congenital viral infection in pregnancy?
Cytomegalovirus
What type of pathogen is cytomegalovirus?
DNA
Most common maternal symptoms of cytomegalovirus?
Asymptomatic
- self-limiting febrile illness
If immunocompromised - pneumonia, hepatitis
Risk of fetal infection with primary infection of cytomegalovirus?
30-40%
Risk highest in 1st/early 2nd trimester
Risk of fetal infection with reactivation of cytomegalovirus?
1-2%
What % of women seroconvert cytomegalovirus in pregnancy?
2%
What is the incubation of cytomeaglovirus?
3-12 weeks
How is cytomegalovirus spread?
Sexual contact/bodily fluids (blood/breast/urine)
What % of congenital CMV show symptoms at birth?
What % later become symptomatic?
90% show no manifestation at birth (10% do)
A further 10% later develop signs in later life
What is the most common cause of congenital sensorineural deafness?
Cytomegalovirus
Fetal risks of CMV
Sensorineural deafness
Hepatopsplenomegaly
IUGR
Microcepahly
Thrombocytopenia
Seizures
How to diagnose fetal infection of CMV?
Amniocentesis 6-8 weeks after seroconversion/reactiveation or >20 weeks
How to manage pregnancy if fetal CMV confirmed?
Detailed USS every 2-3 weeks
Fetal MRI 28-32 weeks
If high avidity IgG CMV are high (>60%), what does this mean
Suggests infection >3 months ago
Advise to avoid contracting CMV - consider for women working in childcare who are pregnancy
Wash hands after changing nappies, wash toys, avoid charing food/cutlery with children, avoid kissing young children
What type of pathogen is toxoplasmosis?
Obligate intracellular protozoan
What is the incubation period of toxoplasmosis
5-23 days
How is toxoplasmosis spread?
Becomes sexually mature in cat intestines, producing oocysts which are excreted in stool. Infection occurs through ingestion of contaminated food including vegetable or infected meat.
Presentation in adults?
Human infection usually asymptomatic / produces glandular fever - like illness. Lymphadenopathy involving the posterior cervical chain is commonest clinical manifestaton.
What % of women become infected with toxoplasmosis during pregnancy?
1:500
Risk of fetal infection with toxoplasmosis if primary infection occurs in:
1st trimester
17%
Risk of fetal infection with toxoplasmosis if primary infection occurs in:
2nd trimester
25%
Risk of fetal infection with toxoplasmosis if primary infection occurs in:
3rd trimester
60%
Risk to foetus with toxoplasmosis infection in pregnancy
10% Eye problems only - choriorentinitis can lead to blindness
20-30% - multiple anomalies - hydrocephalus, cerebral microcalcifications, jaundice, thrombocytopenia
60% no symptoms
Organ most commonly effect is the eyes 👀
How to Dx toxoplasmosis in pregnancy, in mother and foetus
Mother - serology - high IgM or 4 fold increase IgG
Fetus - amniocentesis 6 weeks after seroconversion
What medication can given to reduce the risk of transmission of toxoplasmosis?
By what % do these medications reduce the risk of transmission?
Spiromycin
or
Pyrimethamine + sulfadazine and colonic acid
70%
