Infections in Pregnancy and Neonates - in Pregnancy and Neonate · PDF file Infections in Pregnancy and Neonates Fiona Cooke & Hamid Jalal Department of Medical Microbiology and...

Infections in Pregnancy and

Neonates

Fiona Cooke & Hamid Jalal Department of Medical Microbiology

and Virology, Addenbrooke’s Hospital

Overview

• Definitions

• Maternal Factors

• Foetal factors

• Neonatal Factors

• Infection: Screening and

Diagnosis

• Cases

http://www.ci.fargo.nd.us/Health/Community/Images/pregnant-woman-closeup.jpg

Recent changes in Epidemiology and

management of infection of foetus and newborn

• Increase in: – Viability of very low birth weight infants

– Multiple births

• Improved Diagnostics: – molecular e.g. PCR, MALDI-TOF Mass spectrometry

• Prevention: – Intrapartum prophylaxis against GBS

– ARV for prevention of HIV transmission

• Spread of multi-drug resistant pathogens in nurseries: – MRSA, ESBL, Pseudomonas aeruginosa

Definitions

• Congenital : Conception to birth

• Abortion: Death of fetus up to 20 weeks of gestation

• Intra Uterine Death: Death of fetus between 21 and 37 weeks of gestation

• Peri-natal : 28th week of gestation to 7 days after delivery

• Stillbirth: Death of fetus after 37 weeks of gestation

• Neonate: A baby up to 28 days of life

• Infant: A child under the age of 1 year

• Labour: The process of expulsion of the fetus and the placenta from the uterus.

Maternal Factors Compromised cellular immunity

• Modest – e.g. severity of malaria in pregnancy

Specific systems at enhanced risk of infection

• urinary tract and uterus

Risk of infection of the products of conception:

• overwhelming – e.g. life threatening septic abortion – large volume infected material + heavy microbial load

• less severe e.g. Q fever – failure of foetal eradication of infection → prolonged maternal ill health

Post delivery ‘surgical’ infection

• episiotomy, Caesarean wound, retained products – Genital tract colonisation by high grade pathogens

• e.g. Group A or B ß-haemolytic Streptococci

Chronic Infections in the mother

• Tuberculosis, HIV, syphilis, malaria, viral hepatitis….

Foetal Factors

Immunocompromised cellular and humoral immunity

• profound (1st trimester) to modest (at term)

Risk of:

• Ascending infections from vaginal flora

• Trans-placental infection :

– Severe consequences

• abortion, premature delivery with infection

• e.g. listeriosis

– Less severe infection but interference with organogenesis

• →congenital malformation

• e.g. rubella

Important causes of trans-placental infection

Viral:

– rubella

– parvovirus

– CMV (very rarely: VZV, HIV)

Bacterial:

– Listeria monocytogenes,

– Treponema pallidum

– Chlamydophila psittaci

– Coxiella burnetii

– Borrelia burgdorferi

– Mycobacterium tuberculosis

Protozoal:

– Toxoplasma gondii

– Plasmodium spp.

– Trypanosomiasis

Symptoms and signs of infection vague and non-specific

↓

Delayed diagnosis

↓

Rapid progression to septicaemia

Widespread dissemination of infection

e.g. to lungs, bones, CNS

↓

Heavy antibiotic use with toxicity

Selection pressure for resistant bacteria and fungi

Managing Neonatal Infection:

Pitfalls

Screening and Diagnosis

• Screening: • An active process to identify the individuals suffering with an

infection or increased risk of disease, with the aim of preventive and therapeutic interventions.

• Antenatal Screening in the UK: – Booking antenatal clinic visit

– HIV, HBV, rubella and syphilis

– MSU

• Screening is not routinely offered for the following: – Hepatitis C, Toxoplasmosis, Cytomegalovirus, HSV,

Group B Streptococcus, Chickenpox, Parvovirus

Prevention

• Avoiding potential hazards – NICE clinical guideline 62 March 2008

http://www.nice.org.uk/nicemedia/pdf/CG062PublicInfo.pdf

– Avoid contact with chicken pox, Parvovirus if non-immune

– Raw meat, unpasteurised dairy products, soft cheese cold meats/pate

– Kittens, cat faeces

• Vaccination – Influenza

• Antibiotic prophylaxis – GBS: Intrapartum Penicillin

– UTI and asymptomatic bacteriuria: antibiotics

– HIV: Anti-retroviral Rx of mother and newborn

http://www.nice.org.uk/nicemedia/pdf/CG062PublicInfo.pdf

Laboratory Diagnosis of

Infections

Specimens Techniques

Mother Blood, body

fluids, swabs,

placenta

Serology, PCR,

culture

Fetus Amniotic fluid,

fetal blood

PCR or culture

Neonate Blood, body

fluids, swabs

Serology, PCR,

culture

Case 1

• 24 -year-old woman.

• 22 weeks pregnant.

• Fever and malaise for 3 weeks.

• What investigations would you do?

– MSU Negative

– Blood cultures Negative

– CMV IgG negative IgM positive.

– Toxoplasma IgG negative.

– Rubella IgG positive Rubella IgM negative.

– Parvovirus IgM negative

– Parvovirus IgG positive

• What is the risk to the baby?

• Can you treat congenital CMV?

• How can we diagnose CMV in the neonate?

Ganciclovir has been tried, does have some effect, but is not

recommended because of toxicity (it rots rats’ gonads!). Do not

use ganciclovir in pregnancy.

- Culture/PCR of urine.

- IgG/IgM seroconversion in mother.

- Only a minority of babies will have IgM at birth.

- They will have mother’s IgG level at birth.

CMV risk to foetus.

40% transmission to baby transplacentally of these

1% severe/fatal infection

10% symptomatic at birth

90% asymptomatic – of which approximately 20% will have

some sequelae

Primary CMV infection

Serology screen –

CMV IgM Toxo IgG, rubella IgM, parvo IgM.

?UTI, ?Listeria, ?Endocarditis – MSU, Blood cultures

Case 2.

• The urine from a healthy 26 year old primi-gravida was tested routinely at booking with the following results:

Normal values

WBC

Case 3

• 24-year-old woman

• 14 weeks pregnant

• Her 3-year-old boy developed chickenpox 2 days ago.

– Is this a problem?

• What should you do?

• She has not had chickenpox before.

– What should you do?

• VZV IgG negative - Not immune

• What action should be taken?

• Will ZIG prevent infection?

• What if she develops chickenpox?

- Yes, chickenpox can cause congenital damage in the child. If

infection in the mother

Case 4.

• 25 year old primigravida presents in the 30th week of pregnancy

H/O

• fever and abdominal pain x 1/7

• previous day noticed a little watery vaginal discharge.

O/E

• tenderness over the uterus,

• Per Vaginal discharge of foul amniotic fluid

• FBC: peripheral neutrophil leucocytosis.

• What is the likely diagnosis?

• What is the likely cause?

• What complications may follow?

• How should she be managed

Intra-uterine infection: anatomically a chorioamnionitis -

infection of foetal membranes

+/- amniotic fluid. Affects 0.9% pregnancies.

Given the history, an ascending infection with vaginal flora,

probably mixed:

E. coli, Streptococci (including Group B), obligate

anaerobes, occasionally Staphylococcus aureus

Intrauterine infection may also be secondary to bacteraemia

(e.g. Listeria monocytogenes) but this is rare

Endomyometritis (19%),

C-Section wound infection (15%),

Bacteraemia/septicaemia (4%),

Spontaneous abortion/preterm labour [

Case 5

• 30 year old Para 1 Gravida 2

• 10th week of pregnancy

H/O

• fever x 4/7 (no other symptoms including rash or vaginal discharge)

• Developed abdominal pains and contractions this morning

• Recently returned from a trip to France : no dietary precautions

O/E

• an oral temperature of 38oC

• CVS: hypotension and tachycardia

• PA: marked tenderness over the uterus

• PV: broken membranes with a fully dilated cervix

• Shortly thereafter she aborted a foetus with no signs of life.

• Cultures of blood and placenta were taken

• Treated with parenteral penicillin + gentamicin + metronidazole

• Condition steadily improved thereafter

Case 5 • What is the likely diagnosis?

•