Congenital Infection
Guidelines for Investigation of Suspected Cases

 

Reviewed by Dr Liz Wilson and Dr MC Croxson
April 2014
Clinical Guidelines Back Newborn Services Home Page

Toxoplasmosis

Cytomegalovirus

Syphilis

Rubella

Infection of the fetus can result in embryonic death, stillbirth, prematurity, intrauterine growth retardation, developmental abnormalities or congenital disease.

Clinical findings are rarely disease specific but include:

  • Low birthweight for gestational age
  • Prematurity
  • Seizures
  • Chorio-retinitis
  • Cataracts
  • Purpura
  • Chronic rash
  • Cerebral calcification
  • Micro-ophthalmia
  • Jaundice
  • Anaemia
  • Hepatosplenomegaly
  • Pneumonitis

The combination of IUGR with any of these features should prompt investigation for congenital infection. The mother’s antenatal (“booking” and/or later) bloods should be checked, including HIV status. Maternal and infant serum should be obtained for toxoplasma, CMV and syphilis serology (see appropriate sections) and infant urine sent for CMV culture. Serology for parvovirus B19 (more commonly a cause of hydrops), HIV, herpes and VZV may also be required according to clinical history and examination.
This guideline clarifies the local practice for investigation as a recent review (de Jong 2013) highlighted several potential problems with “Torch testing”.

See also: Hepatitis C  and HIV 

Toxoplasmosis

Investigation

  1. Babies born to Toxoplasma IgM positive mothers

N.B. even if amniocentesis has been performed with positive toxoplasmosis PCR confirmation of infection in the baby should be sought.

  1. Cord blood - label clearly 'cord blood'.
  2. Placenta - Multiple small (<20g) samples taken from various sites around the placenta – mainly from fetal side near umbilical cord): place aseptically in sterile disposable plastic container. Keep chilled. For toxoplasma PCR.
  3. Placenta also should be sent for histology.
  4. Amniotic fluid - collect where available as this may be very informative - 10ml in sterile plastic container for toxoplasma PCR.
  5. Newborn serum - 1ml plain blood (red top) for toxoplasma IgG and IgM. Label clearly 'newborn serum - not cord blood' and request endpoint titre for IgG, see below.
  6. Maternal serum for toxoplasma IgG and IgM

The newborn blood and maternal blood will allow direct comparison of maternal and fetal antibody levels, i.e, is there any evidence of fetal infection as revealed by fetal antibody production? Cord blood is proving unreliable for antibody titration. Please request end point titre so that if level is >200 I.U./ml the lab will dilute the serum further. The lab must be telephoned with this request as it is not standard practice.

All these samples should be sent to:
Department of Virology & Immunology
Level 2, Building 31
LabPlus

  1. Babies in whom congenital toxoplasmosis is suspected after delivery
  1. Maternal serum for toxoplasma IgG (end point titre, see above) avidity, and IgM.
  2. Infant serum (red top) for toxoplasma IgG (end point titre, see above) and IgM; and infant blood (CPD or EDTA tube) for toxoplasma PCR
  3. Head ultrasound
  4. CSF for M, C and S, protein, glucose and toxoplasma PCR : please discuss case first with paediatric infectious diseases team as this may not be required if low risk
  5. Ophthalmology review
  6. Audiology
  7. Refer to Paediatric Infectious Diseases Team for treatment and follow up and ensure mother’s NHI and relevant results are included in the referral.

Cytomegalovirus

  1. There may be a history of maternal 'mono'-like illness.
  2. Most infected infants are asymptomatic but may have later deafness or learning disability.
  3. Approximately 15% of infants born after primary infection of mothers will have one or more sequelae of intrauterine infection.
  4. CMV infection may show more marked liver involvement than congenital toxoplasmosis with hepatosplenomegaly and jaundice.

Investigation

  1. Urine culture for CMV (must be in first two weeks of life to confirm congenital infection). Minimum volume 2ml. Urine must be chilled and transported immediately to the lab on melting ice.
  2. Cord or infant blood for CMV PCR (EDTA or CPD tube).
  3. Head ultrasound

Long term: serial audiology and developmental assessment, head circumference, ophthalmology. Click here to link to: Nursing Care of Infants who are CMV positive

Treatment

The recommendations for treatment of congenital CMV are evolving: please consult the paediatric infectious disease team.

Syphilis

Evaluation of newborn for syphilis is indicated if:

  1. Maternal syphilis not or inadequately treated
  2. Maternal syphilis has been treated but with inadequate follow up or without demonstration of expected fall in non-treponemal antibody titre.
  3. Syphilis in pregnancy treated with non-penicillin regimen (e.g. erythromycin).
  4. Syphilis treated within one month prior to delivery.

Or if any of the following clinical features present:

The above are relatively specific for congenital syphilis, compared with other nonspecific signs of congenital infection:

  1. Hepatomegaly +/-splenomegaly (NB splenomegaly alone does not occur with congenital syphilis but can with congenital CMV)
  2. Jaundice.
  3. Non-immune hydrops fetalis (NB check for parvovirus)
  4. Generalised lymphadenopathy.
  5. CNS signs, elevated cell count or protein in CSF.
  6. Haemolytic anaemia, DIC, thrombocytopenia.
  7. Pneumonitis.
  8. IUGR; failure to thrive.

Investigations

  1. FBC, LFTs and syphilis serology on infant blood.
  2. Maternal syphilis serology.
  3. Infant CSF for VDRL, cells count and differential, protein and glucose concentrations. (please discuss with paediatric I.D. first – the need for this will depend on the level of risk of infection and timely availability of serology results).
  4. Long bone radiographs
  5. Darkfield microscopy of skin lesions, nasal discharge, placental tissue or amniotic fluid may show spirochaetes (but majority of cases have none of these). Discuss with microbiology lab first.

Refer to Paediatric Infectious Disease Team for treatment advice and follow up. Please ensure full information on the mother’s serology and treatment is included in the referral and provide her NHI number.

Symptomatic babies require treatment as soon as possible after investigations are complete, with 10 day course of benzyl penicillin.

Isolation

Gloves should be worn for handling babies with suspected congenital syphilis as moist open lesionsof skin and mucous membranes, secretions and possibly blood are contagious until 24hrs of penicillin treatment has been completed
 

Rubella

Investigations

Mother
  • Check antenatal serology and perform if result not available
    NB maternal IgM may clear within a couple of months so IgG alone in later pregnancy does not exclude primary infection in early pregnancy.
Baby
  • Urine +/- CSF for rubella virus PCR.
  • White blood cells (cord blood or infant blood) for rubella PCR (EDTA or CPD tube).
  • Serum (cord or infant blood) for rubella IgM.
  • Ophthalmology and cardiology referral.

Isolation

Resources

1 de Jong EP, Vossen AC, Walther FJ, Lopriore E. How to use neonatal TORCH testing. Arch Dis Child Educ Pract Ed. 2013 Jun;98(3):93-8.
2 www.asid.net.au