36. Infectious diseases in pregnancy. Bacterial and parasite infections

Question 1

what are the potential complications of mom being an asymptomatic carrier of GBS?

Answer 1

• Preterm labor, premature rupture of membranes = (PROM).
• Chorioamnionitis, fetal/neonatal infections.
• Pyelonephritis.
• Endometritis.
• Neonatal sepsis can develop within 6-12 h’ of birth with signs of neonatal respiratory distress syndrome (NRDS), apnea, shock.

Question 2

how to prevent GBS infection to the fetus?

Answer 2

Vaginal and rectal GBS screening (culture-based) recommended for all pregnant women.

Question 3

when is Intrapartum prophylaxis indicated for GBS infection

Answer 3

• Previous infant with GBS infection.
• GBS bacteriuria during current pregnancy.
• Positive GBS screening during current pregnancy.
• Unknown GBS status (culture not done, incomplete or unknown result) with any of the following criteria: delivery at < 37 w’ gestation, amniotic membrane rupture > 18 h’, intrapartum fever (> 38.0°C).

Question 4

what is the 1st line treatment for GBS infection?

Answer 4

Ampicillin
For penicillin allergy: cefazolin if anaphylaxis risk is low;
erythromycin/clindamycin/ vancomycin if anaphylaxis risk is high.

Question 5

what stage of syphilis may result in fetal infection?

Answer 5

Any stage of maternal syphilis may result in fetal infection.
Treponema pallidum spirochetes cross the placenta and cause congenital infection.

Question 6

how do newborns present with syphilis infection?

Answer 6

jaundice, hepatosplenomegaly, skin lesions, deafness, bone and teeth abnormalities, rhinitis, pneumonia, myocarditis, nephrosis.

Question 7

US findings seen in a fetus with syphilis

Answer 7

edema, ascites, hydrops, thickened placenta

Question 8

diagnosis of syphilis (newborn/mother)

Answer 8

One screening test (RPR, VDRL) should be followed by one confirmatory test (TPPA, FTA- ABS, ELISA, dark-field microscopy)

Question 9

treatment of choice for all stages of syphilis

Answer 9

Penicillin (2.4 million units IM penicillin-G)
If a patient is penicillin-allergic, she must be desensitized and still treated with penicillin

Question 10

presentation of toxoplasmosis

Answer 10

1. Maternal infection: mostly asymptomatic; occasionally may cause mononucleosis-like
   illness (heterophile negative mononucleosis).
   2.fetus infection: may be localized to CNS. Severity
   of fetal infection depends on the gestational age at the time of the maternal 1° infection.

Question 11

Classic triad of newborn toxoplasmosis complications

Answer 11

chorioretinitis, intracranial calcifications, hydrocephalus. Can also cause mental retardation and blindness.

Question 12

how to confirm diagnosis of toxoplasmosis

Answer 12

1. By seroconversion of IgG and IgM or > 4-fold rise in paired specimen.
2. If high-avidity IgG found, infection in the preceding 3-5 months is excluded.
3. PCR for T. gondii in amniotic fluid.

Question 13

treatment for toxoplasmosis

Answer 13

Mom during pregnancy → spiramycin.
Newborn if infected → pyrimethamine + sulfadiazine + folinic acid (rescue).