TORCH testing (sometimes called TORCHES testing) includes tests for a group of infectious diseases that can infect pregnant women and cause birth defects or death in their infants. TORCHES is an acronym for the following infectious diseases:
Toxoplasma gondii (toxoplasmosis)- a parasite that can be acquired from ingesting cysts from the feces of infected cats, drinking unpasteurized milk, or eating undercooked contaminated meat. Infection early in pregnancy can cause miscarriage. Later in pregnancy it can cause eye infections, and mental retardation.
Other– Other infections that may be screened for at the same time include Parvovirus B19 and sometimes varicella zoster virus (chicken pox).
Rubella (German Measles)-Infection early in pregnancy can cause birth defects such as heart disease, growth retardation, and eye defects. It can also cause problems later in childhood such as hearing loss. Following the introduction of the vaccine in the 1970s, the incidence of Rubella has now dropped to approximately 1 in 10,000 births.
Cytomegalovirus (CMV)- This virus is transmitted through body secretions (including breast milk) as well as sexual contact. Infection can cause death, hearing loss and mental retardation.
Herpes simplex virus (HSV)- is a common infection that is spread by oral and genital contact. Most infections are spread to infants during the birth process. Infected infants may have localized infections of the mouth, eyes or skin, and some may have disseminated infection. Infant mortality from neonatal infection can be very high.
Syphilis (Treponema pallidum) – this bacterial infection can cause stillbirth or infant death shortly after birth. Untreated babies may become developmentally delayed, have malformations, seizures, or die.
In practice, TORCH testing in the United States is most commonly targeted toward high-risk groups, or women from areas where the prevalence of the diseases is high. In these situations, the screening serves to identify women with active infection as well as those who lack immunity to the diseases. Those who aren’t immune can be vaccinated or more specifically counseled to limit risk of exposure.
The use of TORCH testing to diagnose these infections is becoming less common since more specific and sensitive tests, that don't rely on the detection of antibodies are available. Note that false positive results are possible and all positive TORCH tests should be followed-up with more specific confirmatory tests.
Routine screening of pregnant women for underlying infectious disease or immunity is consistently performed to identify:
In fact, the CDC 2010 "Sexually Transmitted Diseases Treatment Guidelines" recommend that pregnant women be screened on their first prenatal visit for sexually transmitted diseases which may include Hepatitis B, HIV, Syphilis as well as Gonorrhea & Chlamydia.
In addition to being tested for sexually transmitted diseases, the CDC also has a list of tips on how to avoid infections during pregnancy.
We will discuss testing for each of these infectious diseases individually in future blogs, so stay tuned!