Obstetrics and perinatal infections

Question 1

How are UTIs different in pregnant women

Answer 1

May be asymptomatic

May lead to pyelonephritis (may ascend to kidneys)

Question 2

How does varicella differ in pregnant women

Answer 2

May be much more severe. More likely to die of varicella pneumonia

Question 3

Most important causes of congenital infections

Answer 3

Cytomegalovirus (most common)
Rubella
Toxoplasmosis 
Syphilis 
Varicella 
Zika

Question 4

Consequence of cytomegalovirus

Answer 4

Only a small minority have severe consequences (cataracts, sensory neural deafness and cataracts)

minor consequences- unilateral deafness

Question 5

How does baby get cytomegalovirus infection

Answer 5

From mother. May be primary or secondary. CMV is a herpesvirus so exhibits latency

Question 6

When is risk of damage to baby greater when mother is infected with CMV

Answer 6

IF this is her very first infection as she doesn’t have antibodies

Question 7

What is maternal infection of CMV like

Answer 7

Mostly always asymptomatic

Question 8

IF a pregnant woman develops a rash, what do you need to do and why

Answer 8

Must exclude maternal rubella- because there is a risk of congenital rubella syndrome

Question 9

How do foetuses get congenital rubella

Answer 9

Transplacental trasmissione to fetus

Question 10

What is the outcome of congenital rubella dependent on

Answer 10

Timing within pregnancy. Whether it is in:

• First trimester
• 12-18 weeks
• After 18 weeks

Question 11

What is the risk of congenital rubella if acquired in first trimester

Answer 11

Multiple developmental defects including CNS, cataracts, heart

Question 12

What is the risk of congenital rubella if acquire in 12-18 weeks

What is the risk of congenital rubella if acquired after 18 weeks

Answer 12

Most likely

Deafness

-NO risk

Question 13

How is congenital rubella preventable

Answer 13

Universal MMR vaccination

Antenatal screening and postpartum vaccination

Investigation of all maternal rash and maternal contact with rash

Question 14

What is a maternal rash more likely to be and what is the consequence of this

Answer 14

Parvovirus B19 infection

• Increased risk of spontaneous miscarriage
• Can cause fatal hydrops

Question 15

Transmission of congenital toxoplasmosis and when does the risk increase

Answer 15

transmission during maternal infection- risk increases with duration of pregnancy

Question 16

What does congenital toxoplasmosis lead to

Answer 16

Brain damage, chloroido-retinitis

Question 17

How do we check for syphilis to stop congenital syphilis

Answer 17

Routine antenatal screening and treatment

Question 18

What can congenital varicella lead to

Answer 18

Skin loss, scarring, usually unilateral, segmented

Impaired limb bud development

Many other, less specific features e.g. microcephaly, cataracts, IUGR

Question 19

What is Zika virus reported with a rise in

Answer 19

Microcephaly (where baby’s head is much smaller than expected)

Question 20

Blood-borne virus infections

Answer 20

HIV
Hep B virus
Hep C virus

Question 21

How can blood-borne virus transmission occur to baby

Answer 21

Antenatally- Transplacental
Perinatally-INfected birth canal, exposure to maternal blood
Postnatally- In breast milk (HIV only

Question 22

How to prevent mother to baby HIV

Answer 22

Maternal antiretroviral therapy to reduce viral load

Elective (planned) caesarian section

No breast feeding

Question 23

How to prevent mother to baby hep b

Answer 23

Preventable by vaccination

Question 24

Difference in management between Hep b and Hep c management

Answer 24

Hep b can be treated so is screened for however there is no intervention for hep c so there is no rationale for screening

Question 25

What are some other neonatal infection

Answer 25

Neonatal septicaemia/meningitis
Neonatal varicella
Neonatal herpes
Opthalmia neonatorum

Question 26

Principal causes of neonatal septicaemia/meningitis

Answer 26

Streptococcus
E.Coli
(less common: listeria monocytogenes)

Question 27

How is neonatal septicaemia acquired

Answer 27

From maternal birth canal/ early rupture of membranes leading to chorioamnionitis

[for listeria monocytogenes, maternal infection is food borne (e.g. soft cheese) , organism resides in GI tract]

Question 28

What does Group B streptococcus cause in pregnant women and how is it acquired

Answer 28

Neonatal pneumonia, septicaemia, meningitis

Colonises perineum/vagina in around 1/4 pregnant women. IT is commonly found as normal GI flora

Question 29

How can a Group B streptococcus infection be managed

Answer 29

IV antibiotics during delivery reduces risk of neonatal infection

Question 30

Risk of maternal varicella in late pregnancy

Answer 30

Baby can be born with chicken pox and mortality rate is high

Question 31

Maternal chicken-pox in late pregnancy management

What drugs can you use

Answer 31

• How long does it take for maternal antibodies to develop and cross the placenta?
• If she goes into labour for at least 7 days after her rash appears, then it will not get life threatening varicella

If tha baby is born within 7 days of onset of maternal rash, then you would give the baby passive immunity through varicella immunoglobulin

Can use prophylactic aciclovir when baby is born

Question 32

How are most neonatal herpes infections acquired

Answer 32

Primary maternal genital herpes

Question 33

Why is neonatal herpes difficult to diagnose

What is the prognosis for neonatal herpes

Answer 33

50% cases have internally disseminated infection without external lesions

-Prognosis is bad. Need to treat as soon as possible

Question 34

Organisms that cause ophthalmia neonatorum (conjunctivitis) and how is it acquired

Answer 34

Gonorrhoea or chlamydia

Infected maternal birth canal