Antenatal Infection 1

Question 1

What are causes of maculopapular rashes in pregnancy?

Answer 1

Rubella
Parvovirus B19
Measles
Streptococcus
Meningococcus
EBV
Syphilis

Question 2

What is rubella? Transmission?

Answer 2

ssRNA virus

Transmission by airborne droplets between close contacts

Question 3

What tests for rubella infection/immunity?

Answer 3

IgM antibody - present in acute infection

IgG antibody - present following infection or vaccination

Question 4

Should a rubella vaccination be given during delivery?

Answer 4

It is a live virus and should not be administered while pregnant
Seek rubella vaccination post-delivery

Question 5

What are clinical features of rubella infection? Incubation period?

Answer 5

Often asymptomatic
Malaise
Headache
Coryza
Lymphadenopathy
Fine maculopapular rash - diffuse

14-21 days

Question 6

What management in maternal rubella infection?

Answer 6

No treatment - self limiting
Supportive/conservative

Woman is infective from 7d prior to onset of symptoms to 4 days after

Question 7

What management in fetal rubella infection?

Answer 7

<12 weeks gestation - high likelihood of defects
- Offer TOP

12-20weeks

• RT-PCR on amniotic fluid samples
• If transmission is present - TOP or US surveillance to identify features of congenital rubella syndrome

> 20 weeks

• no additional risk
• no action required

Question 8

What defects does congenital rubella infection cause?

Answer 8

Congenital cataract
Sensorineural Deafness
Cardiac lesions - pulmonary stenosis, PDA, VSD
Learning disability, Microencephaly

Later:
DM
Thyroiditis
Behavioural disorder

Question 9

What is cytomegalovirus?

Answer 9

Herpes virus 5

Question 10

How is CMV diagnosed?

Answer 10

Maternal:
Viral serology for IgM and IgG
- CMV specific IgG i mother previously seronegative (seroconversion)
- Presence of CMV IgM and low IgG

Fetal:
Amniocentesis and PCR
- After 21 weeks gestation

Question 11

What problems can congenital CMV cause?

Answer 11

IUGR
Hepatosplenomegaly
Thrombocytopaenia
Jaundice
Chorioretinitis
Microcephaly

Motor and cognitive impairment
Sensorineural deafness

Question 12

What is management of fetal CMV infection?

Answer 12

Termination of pregnancy offered

Serial US if continued pregnancy

Question 13

What is parvovirus B19

Answer 13

ssDNA virus
Transmitted by respiratory droplets or blood
4-20 day incubation

Question 14

Clinical features of parvovirus B19

Answer 14

Asymptomatic

In children:
Slapped cheek 
URTI
Malaise
Arthralgia

Question 15

What investigations in parvovirus B19

Answer 15

Viral serology
IgM - recent infection
IgG - past infection and immunity

Question 16

What problems can parvovirus B19 cause in pregnancy?

Answer 16

Cardiac failure
Fetal hydrops

Fetal suppression of erythropoiesis

Question 17

What is management for parvovirus B19?

Answer 17

Serial USS and Doppler
Look for signs of fetal anaemia - fetal hydrops and abnormal middle cerebral artery Doppler

If evidence of hydros - tertiary centre for intrauterine erythrocyte transfusion

Question 18

What is fetal hydrops? Why does it occur?

Answer 18

Ascites
Subcutaneous oedema
Pleural effusion
Pericardial effusion
Scalp oedema
Polyhydramnios

Parvovirus B19 has affinity for erythroid system and replicates within erythroid progenitor cells of liver and bone marrow
This induces severe anaemia resulting in:
High output cardiac failure
Increased extraepatic and hepatic erythropoiesis resulting in portal hypertension, hypoproteinaemia and ascites