The Test Sample
What is being tested?
TORCH is an acronym for a group of infectious diseases that can cause illness in pregnant women and may cause birth defects in their newborns. The test is a screen for the presence of any of the antibodies to these infections. Confirmation of an active infection may require more specific tests.
The following tests make up the TORCH panel: Toxoplasmosis, Rubella, Cytomegalovirus, and Herpes simplex virus.
- Toxoplasmosis is a parasitic infection that can be passed from mother to baby through the placenta during pregnancy. An infection with Toxoplasma gondii can cause eye and central nervous system infections as well as brain and muscle cysts. If acquired during the pregnancy, it may result in a miscarriage or cause birth defects, though this depends on the time during the pregnancy in which the infection was acquired by the mother. Toxoplasmosis is acquired by ingesting the parasite when handling the excrement of infected cats, drinking unpasteurized goat's milk, and, most commonly, by eating contaminated meat.
- Rubella is the virus that causes German measles. If contracted early in the pregnancy, the infant may develop heart disease, retarded growth, hearing loss, blood disorders, vision problems, or pneumonia. Problems that may develop during childhood include central nervous system disease, immune disorders, or thyroid disease.
- Cytomegalovirus (CMV) is another viral infection that a mother may have acquired. More than half of all American adults have been infected with CMV at some point in their life and, in most cases, it does not cause severe illness. However, it may pass to the fetus during the birth process and can also infect newborns through breast milk. Infected infants may have severe problems, such as hearing loss, vision problems, mental retardation, pneumonia, and seizures.
- Herpes simplex virus (HSV) is a common viral infection. The two most common infections with HSV are "cold sores" affecting the lips and genital herpes. Both of these infections can recur. HSV is most commonly acquired through oral or genital contact. Newborns who contract the virus usually do so during travel through the birth canal of a woman who has a genital infection with HSV. The virus may spread throughout the newborn's body, attacking vital organs. Treatment with specific antiviral medication should begin as soon as possible in the infected newborn. Even if treated, surviving babies may have permanent damage to the central nervous system.
Other infections that may be screened for at the same time include syphilis, hepatitis B, human immunodeficiency virus (HIV), enterovirus, Epstein-Barr virus, varicella-zoster virus, and human parvovirus.
How is the sample collected for testing?
A blood sample is required for the test. Blood can be collected by a heelstick from an infant, or a needle is used to draw blood from a vein in the arm.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.