O&G Written - Infections Flashcards
Congenital Toxoplasmosis key features
Cerebral calcification
Chorioretinitis
Hydrocephalus
Congenital Rubella key features
Sensorineural deafness
Congenital cardiac abnormalities e.g. PDA
Congenital cataracts
Glaucoma
Congenital cytomegalovirus key features
Growth retardation
Purpuric skin lesions
Diagnostic Ix for CMV infection in pregnancy
USS - may show hepatic or cerebral calcifications (but only minority)
Specific CMV testing
- CMV IgM
- CMV IgG
- viral culture?
What follow up Ix is needed if confirmed CMV infection during pregnancy?
Amniocentesis at least 6 weeks post-infection
To confirm/refute vertical transmission
Delivery recommendations in maternal Herpes Simplex infection
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
Role of acyclovir in maternal HSV?
Primary infection - 5 days oral acyclovir 3x day 400mg
THEN daily in 3rd trimester
- primary and recurrent
Management of chickenpox exposure in pregnant woman
Previous chickenpox = safe
Unsure?
- Measure Varicella IgG
- Immune = safe. Non immune = VZIG ASAP (within 20 days) if <20/40 OR 7-14 days post exposure if >20/40
Maternal chickenpox - management for mum & baby
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)
Features of congenital varicella syndrome
Foetal growth restriction Skin scarring Eye defects Limb hypoplasia Neuro - microcephaly, hydrocephalus etc.
Management of confirmed maternal rubella infection
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
Pattern of Rubella transmission risk during pregnancy
Risk of congenital rubella syndrome DECREASES as gestation increases
- 90% <8-10 weeks
- 10-20% <16 weeks
Foetal signs of parvovirus infection on USS
Initially anaemia –> increased blood flow velocity in middle cerebral artery
THEN cardiac failure –> oedema (non immune hydrops fetalis)
Management of maternal parvovirus b19 infection
Referral to foetal medicine
- regular uss to identify anaemia / complications
Intrauterine blood transfusion if needed
NOT an indication for TOP
Markers of protection / infectivity in Hep B
surface antibody (HBsAb) = ‘immunologically cured’, low infectivity
e antigen (HBeAg) = infectious
surface antigen (HBsAg) without Ab = infectious
Management of maternal Hep B
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)
Management of maternal Hep C
alpha or lymphoblastic interferon usually + ribavirin - contraindicated in pregnancy
Zepatier (elbasvir + grasoprevir) +/- ribavirin has unknown safety in pregnancy
Rate of chronic Hep B carriage in neonates vs adults
90% neonates
10% adults
Neonatal HIV ART regimens
Low-medium risk = Zidovudine mono therapy 2-4 weeks
High risk = triple agent PEP (2 NRTI + II) for 4 weeks
Neonatal HIV testing schedule
At birth On discharge 6 weeks (2 weeks after stopping Tx) 12 weeks (8 weeks after stopping Tx) 18 months
Risk factors for maternal –> infant GBS transmission
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
Indication for GBS testing?
GBS +ve in previous pregnancy
Maternal Tx of GBS
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
Neonatal monitoring & Tx in maternal GBS
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
