Toxoplamsa gondii: Diagnosis of congenital toxoplasmosis infection of the child

Description of tests

• Serological techniques: Detection of IgM antibodies in the newborn (cord blood and/or neonatal blood). Comparison of IgG profile with maternal antibodies by immunoblot. Serological follow-up of IgG antibodies during the first year of life : the persistence of IgG after one year of age or the increase in IgG antibodies in children during the first year of life suggest congenital infection.
• Molecular techniques: detection of the parasite in the child’s CSV and blood and placenta by PCR.

Purpose of tests

To confirm or rule out congenital infection in the newborn.

Criteria for performing this test

• The reference centre performs these analyses in newborns and children of women who have experienced proven or suspected toxoplasmosis during pregnancy, and in newborns with clinical signs of congenital infection at birth, irrespective of the presence or absence of pregnancy follow-up.
• To organise proper follow-up and initiate possible treatment, samples should be collected during the first days of life.

Instructions for samples and transport

For serology: at least 0.5 ml of serum, is required to allow all necessary tests to be performed:

• For unfrozen serum: transport at room temperature
• For frozen serum: preferably transport in frozen condition

For molecular techniques:

• CSV/ blood: min. 0.3 ml, stored at 4°C; send as soon as possible after collection, at room temperature
• Placenta: minimum 4 mm punch ml in physiological serum or universal transport medium.

The laboratory will decide whether to perform the test based on the medical information. Please provide the necessary medical information on the request form.

Unacceptable requests

• Incomplete request form
• Sample not suitable for analysis
• Incorrect transport/storage
• Insufficient volume

Turn around time 

Depends on the number of tests to be performed. Response time can be up to 1 week.

Reporting of test results

The reference centre reports the results and comments and sends it to the requesting laboratory by mail, fax or via medibridge (UZBrussels).