Obstetrics and Perinatal Infections

Question 1

Risk factors modifying infective risks in pregnancy

Answer 1

• Immunological changes
• Physiological
  
  • Stasis in the urinary tract

Question 2

Main maternal infections that can give rise to congential infections

Answer 2

TOxoplasmosis

Rubella

Cytomegalovirus

Herpes simplex virus

TORCH

Question 3

Cause, features, prevention of Toxoplasmosis

Answer 3

Cause: Toxoplasma gondii; a protozoon

• Transplacental transmission, risk greatest early pregnancy

Clinical feature: Brain damage, choroido-retinis

Prevention: Hygiene cats

Question 4

Cause, features, prevention of Rubella

Answer 4

Transplacental

Outcome depends on timing:

• First: CNS, eye, heart, congenital rubella syndrome
• 12-18: deafness
• 18 weeks+ no risk

Preventable by MMR. INvestigate all maternal rash

Question 5

Cause, features, prevention of congenital CMV

Answer 5

• Member of herpes virus family, all herpes virus go latent
• 3/1000 births
• Majority normal at birth
• Some severe cases; deafness, hepatosplenomegaly

Question 6

Cause, features, prevention of maternal CMV

Answer 6

• Primary (STI, salivay etc) or secondary (from latent laten herpes)
• Both give congenital infection and foetal damage, primary worse
• Maternal infection mainly asymptomatic

no vaccine

Question 7

Cause, features, prevention of Varicella

Answer 7

• Reaction of herpes virus in utero-> skin loss, scarring like shingles, unilateral and dermatomal
• Impaired limb bud development
• 1-2% risk following maternal infection in first 20 weeks

Question 8

How can blood-borne viruses spread to foeatus

Answer 8

• Antenatally - transplacental
• Perinatally - Main, in infected birth canal
• Postnatall - In breast milk (HIV only)

Question 9

Prevention of HIV spread from mother to baby

Answer 9

Overall 20% risk, but preventable

• Maternal antiretroviral therapy to reduce viral load
• C section to avoid perinatal transmission
• No brestfeading

Question 10

Cause, features, prevention of Neonatal septicaemia meningitis

Answer 10

• Main cause Strep B and E.coli
• Life threatening
• From birth canal or early rupture of membranes
• GBS
  
  • Important cause of neonatal pneuomnia, septicaemia and menigitits
  • Comm in GI flora, colonice perineum/vagina in 25%
  • Neonatal risk greatly reduced by antibiotics

Question 11

Cause, features, prognosis of neonatal herpes

Answer 11

• From primary maternal genital herpes at term
• Awful prognosis
• Brain damage, lungs, liver

Question 12

Causes of Opthalmia NEONATURUM

Answer 12

Acute purulunt conjunctiivts from Neisseria gonnorhoa or chlamydia, thracomatis

Acquired perinatally