This is a blood test that screens for several infections that may be present in the newborn, including Toxoplasmosis, Rubella, Cytomegalovirus, Herpes simplex and HIV (hence the name), and other infections. Sometimes the test is spelled TORCHS, where the extra S stands for Syphilis.
How the test is performed
The area from which blood will be drawn (usually finger) is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. Cotton or a bandage may be applied to the puncture site if there is any continued bleeding.
How to prepare for the test
For specific information regarding how you can prepare your child, see Infant test or procedure preparation.
How the test will feel
While the blood sample is being obtained, your child will most likely feel a prick and a brief stinging sensation.
Why the test is performed
This test is used to screen infants for certain congenital infections (infections transmitted from mother to fetus/newborn via the placenta). Infections like toxoplasmosis, cytomegalovirus, herpes simplex, Syphilis and others may lead to malformations, growth delay, and neurological problems.
The TORCH screen is one way to assess whether your child has a congenital infection. In some cases, the mother may also need to be tested to help diagnose certain congenital infections.
Proper interpretation of these blood tests requires an understanding of the immune response of infants, as well as the passage of antibodies via the placenta from the mother.
What abnormal results mean
If high levels of immunoglobulin IgM against a particular microorganism are detected in the infant, there may be congenital infection. A definitive diagnosis requires culturing or direct detection of the microorganism.
What the risks are
Blood draws carry a small risk of bleeding, bruising, and infection at the involved site.
The TORCH screen is useful in narrowing down the possibility of a congenital infection, but if the result is positive, a definitive diagnosis will require additional testing. The mother will also need to be evaulated in order to interpret the newborn’s blood tests.
by Harutyun Medina, M.D.