Obstetrics and perinatal infections

Question 1

Outline risk factors modifying infective risk in pregnancy

Answer 1

Immunological/physio changes eg stasis in urinary tract
Many drugs are contraindicated
Urinary tract infections may be asymptomatic or lead to pyelonephritis
Varicella->develop varicella pneumonia
Maternal rash
-> rubella
-> parvovirus B19-> no congenital risks but in increased risk of mis carriage

Question 2

Toxoplasmosis

Answer 2

Toxoplasmosis gondii- protozoan
Transplacental transmission- risk increases with preg duration
RIsk of foetal damage greatest in early preg
CF- brain damage- choroido-retinitis (later life)
Prevent- care with hand hygiene/cats
Spread in soil, cat faeces

Question 3

Rubella

Answer 3

Seen in UK when pregnant/infected abroad
1st trimester- DID, congenital rubella syndrome- CNS, eyes, cataracts
Deafness
>18 weeks- no risk
Prevention- entirely preventable- MMR vaccine
stopped now

Question 4

Cytomegalovirus

Answer 4

Most common
Maternal CMV infection
Primary- during preg-acquired- high risk
Secondary- reactivated, antibodies cross placenta
See on ultrasound
Foetal damage
Handicap, unilateral deafness
Prevent- no screening, vaccine>

Question 5

Syphilis

Answer 5

Multisystem range of CF
Routine antenatal screening
Sensitive to penicillin

Question 6

Congenital varicella

Answer 6

Varicella embryopathy
Skin loss, scaring, usually unilateral
Impaired limb bud development
Many other less specific features-> microcephaly, cataracts, IUGR 1-2% risk following maternal varicella in first 20 weeks of pregnancy

Question 7

List three routes of Blood Bourne virus transmission

Answer 7

Antenataly-> transplacental
Perinataly-> infected birth canal, exposure to maturation blood
Postnatally-> breast milk-> only HIV

Question 8

Mother to baby HIV

Answer 8

20% risk
Preventable by:
-> maternal antiretroviral therapy to reduce viral load
-> elective Caesarian 
-> no breast feeding 
Antenatal screening

Question 9

Mother to baby HBV

Answer 9

5-90% transmission rate 
Neonatal infection leads to very high carriage rates
Preventable by vaccination 
-> active-> accelerate course
-> passive-> hep B immunoglobin 
Universal antenatal screening-> HBsAg

Question 10

Neonatal septicaemia/meningitis

Answer 10

Group B streptococcus and e coli
Life threatening
From female birth canal, early membrane rupture- chorioamniocitis
Antibiotics + listeria monocytogenes
Acquired from mat rectum and anus

Question 11

Maternal chickenpox (varicella)

Answer 11

In mother-> varicella pneumonia
-> in first 20 weeks-> risk of fetal damage
->late pregnancy-> neonatal infection
Delivery >7 days after maternal rash-> safe
VZIg to neonates
Prophylactic aciclovir

Question 12

Neonatal herpes

Answer 12

1st gen herpes at term, infection- liver, lungs, brain damage

Question 13

Opthalmia neonatium

Answer 13

Acute purulent conjunctivitis, N gon or chlamydia
Neonatal pneumonia
Acquired perinatally