Infections (Obs): Listeria, parvovirus, Rubella, toxoplasmosis

Question 1

What is Listeria infection?

Answer 1

Infection caused by Listeria monocytogenes.

Question 2

What is the aetiology of Listeria infection?

Answer 2

Found in soil, decayed matter and animals. Transmission by FOR in soft cheese, pate, unpasteurised cheese, unwashed salads. Vertical via transplacental or delivery.

Associations / Risk factors
Increased risk of infection in pregnancy and immunosuppression

Question 3

What is the epidemiology of Listeria infection?

Answer 3

1/20k pregnancies in UK.

Question 4

What is the history/ exam of Listeria infection?

Answer 4

D&V, malaise, fever, sore throat, myalgia. May be asymptomatic.
No specific signs.

Question 5

What is the pathology of Listeria infection?

Answer 5

Gram+ bacillus

Question 6

What investigations do you do for Listeria infection?

Answer 6

Micro: blood culture, amniotic culture, placental culture (Serological test not available)

Question 7

What is the management of Listeria infection?

Answer 7

IV Abx (penicillin and gentamycin (penic + an aminoglycoside))

Question 8

What are the complications/ prognosis of Listeria infection?

Answer 8

General: septicaemia, pneumonia, meningitis

Pregnancy: miscarriage, stillbirth, chorioamnionitis, PTL, death.

Good prognosis if treated, poor with septicaemia (mortality 50%). Meningitis (70%) or if neonatal infection (80%).

Question 9

What is Erythema infectosum infection?

Answer 9

Erythema infectuosum (Fifth disease) caused by PVB19.

Question 10

What is the aetiology of Erythema infectosum infection?

Answer 10

Transmission aerosol, also blood borne.

DDX: RUBELLA!

Children or susceptible adults.

Question 11

What is the epidemiology of Erythema infectosum infection?

Answer 11

Common infection, 60% immune by 20. 1/400 pregnancies.

Question 12

What is the history/ exam of Erythema infectosum infection?

Answer 12

Rash, malaise, fever, arthropathy. May be asymptomatic.

Slapped cheek rash, may have purpura, may have erythema multiforme.

Question 13

What is the pathology of Erythema infectosum infection?

Answer 13

Small ssDNA virus. Incubation 13-20d. Infective from 10d before rash and until disappearance of rash. Risk period for transmission to fetus between 4-20/40. No IU transmission under 4/40. Low risk of hydrops fetalis after 20/40.

Question 14

What investigations do you do for Erythema infectosum infection?

Answer 14

Blood: PVB19 serology (IgM acute, IgG past). Rubella serology (similar presentation)

USS: fetal anomaly scan at 4wk pot onset of illness, then 1-2wk intervals until 30/40.

Question 15

What is the management of Erythema infectosum infection?

Answer 15

Maternal: symptomatic tx, self limiting

Neonate: Intrauterine blood transmision (if fetal hydrops)

Question 16

What are the complications/ prognosis of Erythema infectosum infection?

Answer 16

Maternal: aplastic anaemia, arthritis, myocarditis, nephritis.

Fetus: miscarriage15%, fetal hydrops 3%.

Untreated fetal hydrops has 50% mortality, reduced to 18% if IUBT. No gcongenital abnormalities.

Question 17

What is Rubella?

Answer 17

Infeciton caused by the rubella virus

Question 18

What is the aetiology of Rubella?

Answer 18

Transmission by aerosol route, vertical (transplacental)

Non immunity (high rates in ethnic minorities)

Question 19

What is the epidemiology of Rubella?

Answer 19

Rare – 97% of women are vaccinated in UK

Question 20

What is the history/ exam of Rubella?

Answer 20

Fever, malaise, coryza, arthralgia, rash

Lymphadenopathy, maculopapular rash (starting behind ears, spread to head and neck, then to rest of body).

Question 21

What is the pathology of Rubella?

Answer 21

RNA virus (togaviridiae) with incubation 6-21d. infectious form 1wk pre and to 5d post rash

Question 22

What investigations do you do for Rubella?

Answer 22

Bloods: Rubella IgM/IgG

USS: fetal anomalies

Question 23

What is the management of Rubella?

Answer 23

Symptomatic tx for mother May offer TOP if confirmed infection in first trimester.

Question 24

What are the complications/ prognosis of Rubella?

Answer 24

Maternal: miscarriage, pneumonia, arthropathy, encephalitis, ITP

Fetal: death, congenital rubella syndrome (deaf, VSD, PDA, cataracts, CNS defects, IUGR, hepatomegaly, thrombocytopenia, rash)

Highest risk is congenital rubella syndrome in first trimester (90%). 510% risk between 14-16/40, low risk after 20/40.

Rubella and congenital rubella syndrome rare since MMR vaccination in 1988.

Question 25

What is Toxoplasmosis?

Answer 25

Infection by toxoplasmosis gondii.

Question 26

What is the aetiology and RFs for Toxoplasmosis?

Answer 26

FOR transmission (infected meat and cat faeces)

Household cats, rural areas, France.

Question 27

What is the epidemiology of Toxoplasmosis?

Answer 27

1/2000 pregnancies

Question 28

What is the Hx/ Ex of Toxoplasmosis?

Answer 28

Fever, malaise, arthralgia. Often asymptomatic.

None. ? lymphadenopathy.

Question 29

What is the pathology of Toxoplasmosis?

Answer 29

Parasite in cat faeces, incubation 5-23d. High risk of vertical transmission with increasing gestational age at infection (5% T1, 80% T3). Risk of congenital toxoplasmosis reduces with increasing gestational age (80% T1, 5% T3).

Question 30

What is the Ix s of Toxoplasmosis?

Answer 30

Bloods: IGM, IgG.

USS: foetal abnormality scan

Other: amniocentesis to detect fetal infection.

Question 31

What is the management of Toxoplasmosis?

Answer 31

ABX: Spiramycin (reduces vertical tranmsission )

Termination: may offer TOP if USS evidence of fetal ifnection.

Question 32

What are the complications and prognosis of Toxoplasmosis?

Answer 32

Miscarriage, PTL, fetal death, congenital toxoplasmosis (hydrocephalus, retinochondtiritis, intracranial calcifications, IUGR, Hsmegaly, Tcpenia, rash)

PGX depends on severity of congential toxoplasmosis