Congenital Infections Flashcards
1
Q
Infections transmitted to fetus
A
- Rubella
- CMV
- HIV
- Varicella zoster virus
- HSV
- Hep B
- Parvovirus B19
- Syphillis
- Toxoplasma gondii
- Listeria monocytogenes
- Mycobacterium leprae
- Zika virus
2
Q
Rubella during pregnancy
A
- Fetus very susceptible during first 3 months of pregnancy
- Congenital rubella
- Affects brain, eyes, ears and heart
- Clinical manifestations include: low birth weight, eye and heart lesions
- Brain: small brain size- mental retardation
- Eye: cataract, micropthalmia
- Ear: hearing defect, organ of Corti affected (80% of infants will be deaf)
- Heart: patent ductus arteriosus, patent interventricular septum
- Liver, spleen: hepatosplenomegaly, thrombocytopenic purpura, anemia
- General: low birth weight, failure to thrive, increased infant mortality
3
Q
CMV during pregnancy
A
- Following primary maternal infection during pregnancy- ~40% of fetuses are infected
- First trimester primary infections result in ~30% of babies w/ sensorineural hearing loss
- CMV reactivation or re-infection in pregnancy results in some protection by maternal IgG- baby still infected but not affected necessarily
- Clinical features: mental retardation, choriodoretinitis and optic atrophy, hearing defects (deafness), hepatosplenomegaly, thrombocytopenic purpura, anemia
4
Q
HIV during pregnancy
A
- Vertical infection from an infected mother- 20-30%
- Vert. trans. may occur transplacentally, intrapartum and postpartum- ~50% of transmissions occur near or during labor/delivery
- Childhood AIDS; ~1/5 infants born to infected mothers infected in utero
- NO EVIDENCE HIV infection of fetus causes structureal anomalies
5
Q
Varicella zoster virus during pregnancy
A
- Skin lesions; musculoskeletal
- CNS abnormalities when fetus infected before 20wks
- Congenital varicella syndrome- diagnosis depends on IgM-pos. cord blood and clinical findings in newborn (risk for fetus transmission decreased the earlier in pregnancy)
- Clinical findings: limb hypoplasia, cutaneous scars, chorioretinitis, cataracts, cortical atrophy, microcephaly
- Herpes zoster does not pose a risk to fetus
6
Q
HSV during pregnancy
A
- Neonatal HSV infection, often disseminated; much higher risk when maternal infection is primary; infection in utero is rare- it does occur a triad of symptoms occur
- Triad of symptoms:
*skin vesicles or scarring
*eye disease- chorioretinitis and keratoconjunctivitis
*microcephaly or hydranencephaly
- Most common route and time of infection is during delivery
7
Q
Hepatitis B virus during pregnancy
A
- Fetal infection can occur- most likely if maternal infection occurs in 3rd trimester
- Chronic active hepatitis- assoc. w/ increased risk of prematurity, low birth weight and neonatal death
- Most infections are asymptomatic- these are more likely to develop into chronic hepatitis and hepatocellular carcinoma
- Symptomatic infants may have hepatosplenomegaly, jaundice and/or icterus
8
Q
Parvovirus B19 during pregnancy
A
- Infection can occur in utero in the fetus
- Infection in utero can result in fetal death (rare), nonimmune fetal hydrops (uncommon) birth defects (eg, eyes and CNS) and prematurity
- ~60-70% of women of child bearing age are susceptible to infection- only 1% exposed to virus are infected
9
Q
Treponema pallidum (syphillis) during pregnacy
A
- Vertical transmission after 4 months gestation
*should be treated beofore w/ penicillin G
- Congenital syphillis
- Rare in US- more common in poor countries
- Clincial features: rhinitis, skin and mucosal lesions, hepatosplenomegaly, lymphadenopathy, abnormalities of bone, teeth, and cartilage (saddle-shaped nose)
- Treponemal IgM can be detected in fetal blood
10
Q
Toxoplasma gondii during pregnancy
A
- Congenital toxoplasmosis
- Clinical features: convulsions, microcephaly, chorioretinitis, hepatosplenomegaly, jaundice, hydrocephaly, mental retardation, defective vision
- NOTE: often no detectable abnormalities at birth- signs appear aftera few years
- Incidence of fetal infection increases from 14% from maternal infection in 1st trimester to 59% in the 3rd
- Dmg is more severe the earlier infection occurs in pregnancy (abortion, stillbirth, disease in newborn)
- Toxo-specific IgM may be detected in cord blood
- Treatment of pregnant woman or infected infant- use spiramycin or sulphadiazine + pyrimethamine + folinic acid
- No vaccine
- Prevention: avoid primary infection via ingesting cysts from cat feces or lightly cooked meat during pregnancy
11
Q
Listeria monocytogens during pregnancy
A
- Congential listeriosis
- Contact w/ infected animals and their feces, consumption of unpasteurized milk or soft cheeses or contaminated vegetables
- Maternal infection leads to bacteremia, then to placenta, then to fetus
- Outomces: abortion, premature delivery, neonatal septicemia, meningitis, pneumonia w/ abscesses or granulomas
- Organism isolated from blood cultures, CSF, or skin lesions
- Treatment- ampicillin + gentamicin
12
Q
Zika virus during pregnancy
A
- Can be passed from a pregnant woman to her fetus (Congenital Zika Syndrome)
- Infection during pregnancy can cause certain birth defects- eg, microcephaly
*other problems: eye defects, hearing loss, impaired growth
- Zika primarily spreads thru infected mosquitoes
- You can also get Zika thru sex (can stay in semen for up to 6months)
- There is no vaccine to prevent or medicine to treat Zika
13
Q
Routine antenatal screenings
A
- Rubella antibody
- Treponema antibody
- Hepatitis B surface antigen
- HIV antibody
- Zika antibody (IgM) and RTPCR
14
Q
Rubella infected fetus diagnosis
A
- Infected fetuses make IgM- found in cord and blood
- Maternal IgG along w/ interferons help control spread in infant
- Virus isolated- infants throats or urine and sheds for a number of months
- RNA detection can help w/ diagnosis
15
Q
Rubella during pregnacy treatment
A
- Live attenuated virus during childhood- MMR
- Pregnancy- contraindicated to vaccination- only safe immediately postpartum
- Vaccinated mother will protect future fetus
- Today- problems more freq. in countries not vaccinating
