Infectious Diseases & Toxins

ToRCH & Childhood Diseases

ToRCH is an acronym for a group of infections that can cause congenital abnormalities and it has become an important part of prenatal care to recognize these infections in the first trimester of pregnancy.

Although the organisms typically cause only asymptomatic or mild infection to the mother, they can have much more serious consequences to the fetus. If the infection occurs during the first three months of pregnancy and if it is a primary infection (newly acquired during pregnancy), the risk of congenital abnormalities is much higher compared to a secondary or reactivated infection. An important part of prenatal care is to recognize these infections in the mother and the fetus and provide suitable care. ToRCH tests measure antibodies against five groups of chronic infections and all of these infectious diseases are associated with congenital abnormalities resulting from maternal infection: • Toxoplasmosis • Rubella • Cytomegalovirus (CMV) • Herpes simplex virus (HSV) • Other infections (usually Syphilis, Hepatitis B, Coxsackie virus, Epstein-Barr virus, Varicella-zoster virus, and Human parvovirus)

For most ToRCH organisms, the initial screening test is based on the detection of antibodies to the organism. Assays are commercially available for the detection of IgG, IgM, or both IgG and IgM antibodies. In most cases, IgG reactivity in the absence of IgM reactivity is indicative of a past infection, while IgM reactivity in the absence of IgG reactivity indicates a current infection. However, for some ToRCH diseases such as toxoplasmosis and CMV, IgG avidity has recently been found to be useful for identifying primary infections. An IgG antibody produced in the first few months following an initial infection has a lower avidity than an IgG antibody produced several months or years later. Consequently, low-avidity antibody can be used to specifically identify high-risk mothers with a primary infection. To protect a fetus from ToRCH infections, early diagnosis through first trimester screening is critical.

Antibody Pairs

CAPTURE DETECTION

C01686M C01688M C01686M

C01687M C01686M C01689M

Listeria

C01729M C01730M C65196M C65194M C65196M C65197M C65063M C65065M C01770M C01776M C01775M C01774M C01775M C01773M C01769M C01773M C01770M C01773M C01774M C01773M C65064M C65065M

Rotavirus

RSV

Antigen Pairs

CAPTURE DETECTION

T. pallidum (Syphilis)

R01681

R01682

R - Reversible