Congenital and Perinatal Infections Flashcards
What is a prenatal infection?
Infection acquired/carried by mother and transmitted to developing foetus
What is a perinatal infection?
Infection transmitted around time of delivery
What is a postnatal/postpartum infection?
Infection acquired after delivery, withing 1st 2 days of life From - Family - Healthcare workers - Community
What is vertical transmission?
Mother > foetus; eg: transplacental
Mother > baby; eg: breast milk
What is horizontal transmission?
One person/baby > another
What is an ascending infection?
Vaginal organisms producing foetal infection
What are the non-specific effects of maternal infection?
Foetal death
Premature delivery
What are the specific effects of maternal infection?
Benign/self-limiting
End-organ damage
Chronic infection
What is the epidemiology of varicella zoster virus (VZV) infection?
Very efficient transmission via respiratory system
Maternal varicella
What is the clinical presentation of VZV in the mother?
Respiratory illness with productive cough and haemoptysis
Chicken pox
What are the factors influencing transmission to the foetus or neonate with VZV?
Congenital varicella
- Primary maternal varicella in 3rd trimester has greatest risk of transmission and mortality
- Chance of earlier transmission if maternal varicella very severe
Perinatal varicella
- Primary maternal varicella just before/after delivery
What is the route of transmission of VZV?
Congenital
- Transplacental
Perinatal
- Respiratory
What are the outcomes of a VZV infection?
Maternal varicella - 2% mortality Congenital varicella - Limb hypoplasia - Dermatomal cicatricial scarring - Microcephaly - Cataracts - Mental retardation - GIT and genitourinary problems Perinatal varicella - Disseminated infection > disseminated intravascular coagulation - 25-30% mortality
What is the treatment and prevention for VZV infection?
Prophylactic varicella zoster Ig - To prevent maternal, congenital, and perinatal varicella - Given to mother/infant within 96 hours of exposure - Can give to preterm babies Acyclovir - To treat acute varicella - Oral/IV, depending on severity Vaccination - Very effective - Given at 18 months - Live attenuated
What is the epidemiology of cytomegalovirus (CMV)?
Primary infection Reinfection with different strain Reactivation of latent infection 10% of CMV IgG positive people shedding at any time More common in developing countries Congenital CMV common
What is the clinical presentation of CMV in the mother?
Sepsis-like symptoms
- Hepatomegaly
- Respiratory distress
- Atypical lymphocytosis
What are the factors influencing transmission to the foetus or neonate with CMV?
Timing of infection during pregnancy irrelevant
Type of infection matters
- Primary infection in mother has 25-50% foetal transmission rate
- Reactivation in 10-30% of mothers, but only 1-3% foetal transmission rate
What is the route of transmission in CMV?
Congenital - Transplacental Perinatal - Breast milk - Cervical secretions - Genital secretions - Urine
What are the outcomes of a CMV infection?
90% of neonates asymptomatic - Still have risk of long-term complications 10% of neonates symptomatic - Very high rates of long-term sequalae - 20-30% mortality - Chorioretinitis/optic atrophy - Deafness - Microcephaly and periventricular calcification - Developmental delay - Behavioural problems - Pneumonitis (rare)
How is a CMV infection diagnosed?
Characteristic activated mononuclear white cells in peripheral blood In mother - IgG - IgM - IgG avidity - Nucleic acid amplification test Confirmation of foetal infection - Amniotic fluid PCR - Cord blood serology/PCR - Guthrie blood spot
What is the treatment and prevention for a CMV infection?
Basic hygiene around toddlers/young children
Avoid pregnancy <6 months after primary infection
Monitor and assess regularly
Ganciclovir
- 6 week IV treatment for symptomatic neonates
Valganciclovir
- Oral follow up treatment for 12 months for symptomatic neonates
What is the epidemiology of rubella?
Peak in winter/spring
What is the clinical presentation of rubella in the mother?
Low grade fever Lymphadenopathy but unusual - Occipital - Post-auricular - Posterior cervical nodes Exanthem - Macropapular rash - Face > trunk > limbs Polyarthralgia/polyarthritis
What are the factors influencing transmission to the foetus or neonate with CMV?
1st trimester key
- Risk greatest in early pregnancy within 1st month
- Declining over time
Very rare in 2nd trimester
What are the outcomes of a rubella infection?
Ophthalmological - Cataracts - Glaucoma - Retinopathy Cardiac - Patent ductus arteriosus - Pulmonary artery stenosis Auditory - Sensorineural hearing loss Others - Meningoencephalitis - Behavioural problems - Increased rates of T1D and thyroid dysfunction
How is a rubella infection diagnosed?
Foetal diagnostic testing - Amniotic fluid - Cord blood Neonatal serology - IgG detection/rising titre - IgM
What is the treatment and prevention for a rubella infection?
Vaccination Don't give vaccination during pregnancy - Vaccinate before if possible - Post-natal No treatment for infection
What is the route of transmission in herpes simplex virus (HSV)?
Perinatal
What are the outcomes of a HSV infection?
Primary infection during pregnancy - Abortion - Intrauterine growth restriction - Preterm labour Primary infection near delivery: 3 disease patterns - Skin-eye-mouth - Encephalitis - Disseminated disease
What is the treatment and prevention for a HSV infection?
Primary infection during pregnancy
- Acyclovir until delivery
- Caesarian section to reduce risk of transmission
Recurrent disease during pregnancy
- Acyclovir to suppress
- Avoid instrumentation during delivery
- Examine neonate carefully for lesions
- Swab eyes/nasopharynx of neonate to detect colonisation
- Treat neonate with acyclovir if infection detected
What is the clinical presentation of parvovirus B19 in the mother?
Commonly asymptomatic Commonly non-specific symptoms - Fever - Muscle pain - Malaise - Diarrhoea - Headache - Nausea May have more specific symptoms - Febrile illness with rash - Arthropathy - Temporary aplastic crisis
What are the factors influencing transmission to the foetus or neonate with parvovirus B19?
Primary infection from weeks 18-20 of pregnancy puts foetus at risk of most serious effects
What is the route of transmission in parvovirus B19?
Transplacental
What are the outcomes of a parvovirus B19 infection?
10% risk of spontaneous abortion
Foetal anaemia and hydrops fatalis in 2nd/3rd trimester
How is a parvovirus B19 infection diagnosed?
Maternal serology
- Classic IgG/IgM pattern for evidence of past infection with immunity vs current infection
What is the treatment and prevention for a parvovirus B19 infection?
No prevention other than avoiding infection
Specialist treatment can reduce foetal death, including intrauterine transmission if anaemic
What are the factors influencing transmission to the foetus or neonate with syphilis?
Stage of infection matters, rather than stage of pregnancy
- 90% transmission if primary syphilis
- 60-90% if secondary syphilis
- 40% early latent
- Low risk if late latent/tertiary
What is the route of transmission in syphilis?
Transplacental
What are the outcomes of a syphilis infection?
Stillbirth in 40% Premature delivery Snuffles - Secretions from nose - Lots of treponemes Hutchinson's teeth Osteochondritis syphilitica Deafness Intellectual disability
How is a syphilis infection diagnosed?
Antenatal serology at 1st visit
Follow-up serology if high risk of infection
What is the treatment and prevention for a syphilis infection?
3 dose intramuscular benzathine penicillin to mother and baby if infected at birth
What is the route of transmission in chlamydia?
From genital tract at delivery
What are the outcomes of a chlamydia infection?
50% transmission if present in mother’s genital tract
25% conjunctivitis
10% pneumonia
May have persistent colonisation
How is a chlamydia infection diagnosed?
Need to look carefully for haemorrhagic conjunctivitis and specifically test for chlamydia
What is the clinical presentation of toxoplasma gondii in the mother?
Usually asymptomatic
May have flu-like symptoms and lymphadenopathy
What are the factors influencing transmission to the foetus or neonate with toxoplasma gondii?
Primary infection during pregnancy dangerous
Highest risk of foetal abnormalities if infected in 1st trimester
What are the outcomes of a toxoplasma gondii infection?
70-90% asymptomatic at birth Can get - Rash - Lymphadenopathy - Chorioretinitis - Hydrocephalus - Mental retardation
How is a toxoplasma gondii infection diagnosed?
Screening usually not recommended
Can check IgG
What are the factors influencing transmission to the foetus or neonate with hepatitis B virus (HBV)?
Stage of infection important
- 90% transmission if eAg positive or PCR positive
- 5% transmission if markers for active infection negative
What is the route of transmission in HBV?
Transmission at birth
How is a HBV infection diagnosed?
Routine antenatal screening for all
What is the treatment and prevention for a HBV infection?
Vaccination
HBV IV Ig for neonate within 12 hours of delivery
What are the factors influencing transmission to the foetus or neonate with hepatitis C virus (HCV)?
Risk of infection depends on mother’s viral load
What is the route of transmission in HCV?
Transmission at birth
What is the treatment and prevention for a HCV infection?
Caesarian section reduces risk of transmission by 30%
Duration of exposure to ruptured membranes during birth affects risk
What is the epidemiology of group B Streptococcus?
In bowel/vagina of 20-30% of women
40-70% babies born to colonised mothers will also be colonised
What are the factors influencing transmission to the foetus or neonate with group B Streptococcus?
Preterm delivery Prolonged exposure to ruptured membranes Intrapartum fever Chorioamnionitis Having previous baby with infection
What is the route of transmission in group B Streptococcus?
Ascending infection
Colonisation at delivery
What are the outcomes of a group B Streptococcus infection?
1% of colonised babies will have invasive disease
- Sepsis
- Pneumonia
- Meningitis
Sepsis and pneumonia more common with early post-natal infection
Colonisation later after birth more likely to cause meningitis
Increases risk of preterm delivery
How is a group B Streptococcus infection diagnosed?
Self-collected vaginal and anal swabs
What is the treatment and prevention for a group B Streptococcus infection?
Penicillin + gentamicin
Can give intrapartum chemoprophylaxis if mother screens positive for carriage
