O&G Written - Infections

Question 1

Congenital Toxoplasmosis key features

Answer 1

Cerebral calcification
Chorioretinitis
Hydrocephalus

Question 2

Congenital Rubella key features

Answer 2

Sensorineural deafness
Congenital cardiac abnormalities e.g. PDA
Congenital cataracts
Glaucoma

Question 3

Congenital cytomegalovirus key features

Answer 3

Growth retardation

Purpuric skin lesions

Question 4

Diagnostic Ix for CMV infection in pregnancy

Answer 4

USS - may show hepatic or cerebral calcifications (but only minority)

Specific CMV testing

• CMV IgM
• CMV IgG
• viral culture?

Question 5

What follow up Ix is needed if confirmed CMV infection during pregnancy?

Answer 5

Amniocentesis at least 6 weeks post-infection

To confirm/refute vertical transmission

Question 6

Delivery recommendations in maternal Herpes Simplex infection

Answer 6

CS if delivery within 6 weeks of primary attack OR genital lesions from primary infection at time of delivery

Vaginal delivery ok if:
- genital lesions in woman with recurrent herpes

Question 7

Role of acyclovir in maternal HSV?

Answer 7

Primary infection - 5 days oral acyclovir 3x day 400mg

THEN daily in 3rd trimester
- primary and recurrent

Question 8

Management of chickenpox exposure in pregnant woman

Answer 8

Previous chickenpox = safe

Unsure?

1. Measure Varicella IgG
2. Immune = safe. Non immune = VZIG ASAP (within 20 days) if <20/40 OR 7-14 days post exposure if >20/40

Question 9

Maternal chickenpox - management for mum & baby

Answer 9

Mum:
- oral acyclovir within 24h of rash onset (if >20 weeks)

Foetus/baby:

• VZIG if baby delivered 5 days after OR 2 days before mum gets Sx + close monitoring
• VZIG if baby exposed (not via mum) in first 7 days of life
• symptoms = aciclovir (discuss with virologist + neonatologist first)

Question 10

Features of congenital varicella syndrome

Answer 10

Foetal growth restriction
Skin scarring
Eye defects
Limb hypoplasia
Neuro - microcephaly, hydrocephalus etc.

Question 11

Management of confirmed maternal rubella infection

Answer 11

Contact PHE / local HPU!

<16-20 weeks

• Urgent referral to Obstetrics / foetal medicine
• risk assessment, counselling
• TOP offered
• +/- Ig in 2ndary care only

> 20 weeks = reassurance +/- vaccination postpartum

Question 12

Pattern of Rubella transmission risk during pregnancy

Answer 12

Risk of congenital rubella syndrome DECREASES as gestation increases

• 90% <8-10 weeks
• 10-20% <16 weeks

Question 13

Foetal signs of parvovirus infection on USS

Answer 13

Initially anaemia –> increased blood flow velocity in middle cerebral artery

THEN cardiac failure –> oedema (non immune hydrops fetalis)

Question 14

Management of maternal parvovirus b19 infection

Answer 14

Referral to foetal medicine
- regular uss to identify anaemia / complications

Intrauterine blood transfusion if needed

NOT an indication for TOP

Question 15

Markers of protection / infectivity in Hep B

Answer 15

surface antibody (HBsAb) = ‘immunologically cured’, low infectivity

e antigen (HBeAg) = infectious

surface antigen (HBsAg) without Ab = infectious

Question 16

Management of maternal Hep B

Answer 16

Routine screening for all women.

High viral load = antivirals from 36 weeks onwards

Hep B Ig + vaccination to neonate if maternal high infectivity.

Vaccination only to infants of Hep B antigen +ve father (discuss with neonatologist first)

Question 17

Management of maternal Hep C

Answer 17

alpha or lymphoblastic interferon usually + ribavirin - contraindicated in pregnancy

Zepatier (elbasvir + grasoprevir) +/- ribavirin has unknown safety in pregnancy

Question 18

Rate of chronic Hep B carriage in neonates vs adults

Answer 18

90% neonates

10% adults

Question 19

Neonatal HIV ART regimens

Answer 19

Low-medium risk = Zidovudine mono therapy 2-4 weeks

High risk = triple agent PEP (2 NRTI + II) for 4 weeks

Question 20

Neonatal HIV testing schedule

Answer 20

At birth
On discharge
6 weeks (2 weeks after stopping Tx)
12 weeks (8 weeks after stopping Tx)
18 months

Question 21

Risk factors for maternal –> infant GBS transmission

Answer 21

Previous infant with early-onset GBS disease
GBS bacteriuria in current pregnancy OR GBS colonisation at term
Prolonged ROM (>18 hours)
Pre-term labour
Maternal intra-partum temp >38

Question 22

Indication for GBS testing?

Answer 22

GBS +ve in previous pregnancy

Question 23

Maternal Tx of GBS

Answer 23

Intrapartum Abx - IV benzylpenicillin

• 3g loading dose at least 4 hours prior to delivery - - then 1.5g every 4 hours
• severe allergy = IV vancomycin instead

ROM after 37 weeks and GBS + –> IOL

Question 24

Neonatal monitoring & Tx in maternal GBS

Answer 24

Abs declined or inadequate cover = 12 hours monitoring

Previous baby with GBS disease (even if sufficient Abx given) = 12 hours monitoring

Term babies clinically well + sufficient Abx given = no special observations

Signs of GBS disease = penicillin + gentamicin within 1 hour

Question 25

Tx of maternal or foetal syphilis

Answer 25

Penicillin G / benzathine penicillin

Question 26

Tx of maternal toxoplasmosis

Answer 26

ASAP = Spiramycin

Vertical transmission confirmed = add pyrimethamine and sulfadiazine + folinic acid