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What is ToRCH?

Dec 22, 2017

ToRCH is a combination of English prefixes of four human pathogenic microorganisms: Toxoplasma gondii (Toxo) virus; R represents Rubella Virus (RV); C represents Cytomegalovirus (CMV); H Representative Herpes Simplex Virus (HSV). These four kinds of pathogenic microorganisms in addition to susceptible populations cause a variety of diseases, but also through the placenta affect the normal early fetal development and cause a variety of congenital diseases, there are two common characteristics:

First, pregnant women due to endocrine changes and decreased immunity prone to primary infection, pregnant women in the past infection of latent pathogens in the body is also vulnerable to recurrent infections, pregnancy infection not only endanger the mother, but can also cause intrauterine infection , Leading to miscarriage, premature birth and stillbirth. Fetal infection, may cause stunting and congenital malformations, resulting in neonatal mental retardation, a variety of paralysis, blindness, deafness, deafness, mentally retarded and other serious consequences on the quality of the population has a direct impact.

The second is the general symptoms of mild infection or no obvious symptoms, not easily detected and ignored, can not feel whether they are infected, so pre-pregnancy and early pregnancy diagnosis of prenatal and postnatal care is very important.

ToRCH infection in perinatal medicine called "ToRCH syndrome", has been the world medical community, especially obstetrics and gynecology and pediatricians attach great importance. ToRCH syndrome is one of the important problems plaguing our country's prenatal and postnatal care for a long time. Pregnant women in the first trimester of pregnancy caused more abortion and congenital malformations, late pregnancy more often lead to premature labor, premature rupture of membranes, neonatal infections. Some potential infections are activated when pregnant women become less active and become active infections.

At present, clinical and laboratory use of detection of pathogen-specific IgG and IgM to diagnose the infection of pregnant women and fetuses. IgM production is generally considered an acute response and IgM is produced within one to three weeks after infection. Maternal blood specific IgM-positive pathogens may occur intrauterine infection. IgM molecular weight, can not pass the placenta, so cord blood detection of pathogen-specific IgM is a diagnostic indicator of congenital infection. The pathogen IgM-positive fetus may have a poor prognosis, can be used as an indicator of fetal choice.

Toxo is a protozoan widely parasitized in humans and in a variety of animal nucleated cells. Toxoplasmosis is a worldwide distribution with a wide range of natural epidemiological zoonotic diseases, the infection is very common, regional differences are enormous, according to serological survey data showed the French population was 80.0% positive rate of the United States 25.O% ~ 33.O%, China's infection rate was 4.O% ~ 9.0%. Congenital toxoplasmosis is one of the most important human congenital diseases, is an important research topic of our eugenics, fertility work. Toxoplasmosis is an important cause of teratology in newborns in our country. To date, at least 38 cases of toxoplasma deformity or birth defects have been reported in China [1], with or without brain, hydrocephalus, macula, microcephaly, bulging meninges, cystic or recessive spina bifida , Skull defect, skull fracture, eyelid disease, small orbit, monocular, cleft palate, gingival cleft, cleft lip, absence of uvula, median nasal cleft, ear shell without round, funnel chest, short arm, Limb varus and valgus, esophageal atresia, anal atresia, esophageal tracheal fistula, rectovaginal fistula, umbilical hernia, polycystic kidney, adrenal absent, visceral valgus, short penis, residual angle uterine malformation, double uterus, double vagina, Yin and Yang, United deformity and so on. Therefore, the susceptible population, especially pregnant women, once on the eve of pregnancy, pregnancy, toxoplasmosis, the risk posed to the fetus is great. Diagnosis mainly by detecting serum antibodies to achieve. Toxoplasma infection can produce immunity, including humoral immunity and cellular immunity. First appeared IgM antibodies, later IgG antibodies, IgG can pass from the mother to the fetus through the placenta, while IgM is not. Therefore, such as IgM antibodies detected in babies suggest the possibility of congenital toxoplasma infection.

Cytomegalovirus (CMV) infection is one of the most common and harmful viruses in pregnancy virus infection. CMV infection is usually invisible infection or only shows mild cold symptoms. Therefore, pregnant women should be vigilant as soon as possible CMV IgM detection, so as to avoid CMV infection and endanger the fetus. Primary infection (pregnant women during pregnancy CMV infection, CMV has not previously been infected), resulting in the highest rate of fetal congenital infection, up to 31% to 40%. However, the incidence of primary infection during pregnancy is low, accounting for only about 4%. CMV infection in pregnant women and 3-month-old fetus, newborn and other groups, especially primary infection, often cause serious clinical symptoms or even death. Pregnancy leads to the suppression of immune function, which promotes the occurrence of CMV primary infection and the activation of latent virus. The active CMV infection during pregnancy makes the immune function further inhibited. The suppression of immune function in infected pregnant women promotes the occurrence of intrauterine infection And lead to serious consequences, miscarriage, premature birth, stillbirth, neonatal death [2]. If alive, the vast majority of CMV-infected neonatal no obvious symptoms and signs. Only about 10% of newborns with low birth weight, jaundice, purpura, hepatosplenomegaly, mental retardation, retinal choroiditis, intracranial calcification, microcephaly, etc., most children died within a few hours to several weeks after birth, died Rates are as high as 50% to 80%. Survivors often have long-term sequelae of mental retardation, hearing loss and delayed central nervous system damage, whereas 5% to 15% of asymptomatic persons develop at 2 years after birth abnormal. General acute infectious disease indicators (IgM) -positive pregnant women, if the fetus in poor condition, such as heart abnormalities, fetal ascites, etc. should immediately terminate the pregnancy.

Rubella virus (RV) belonging to the genus Togaviridae in the herpes virus genus Rubella virus, is the cause of rubella pathogens, RNA viruses. Virus spread through the respiratory tract, the incubation period of about 2 to 3 weeks, the virus proliferates into the blood to cause viremia. The clinical manifestations of rubella are similar to those of measles but less severe than those with measles infection and few comorbidities. Adults infected with rubella virus have symptoms such as common cold, general symptoms and ear and suboccipital lymph nodes, followed by facial reddish rash and rapid spread throughout the body. More in 1 to 3 days subsided, the prognosis is good. The rate of infection in the population is about 95%, often overlooked. Pregnant women are infected with rubella virus within 6 months of pregnancy and can infringe the fetus through the placenta (vertical transmission). In addition to causing miscarriage and stillbirth, about 29% of live births show "congenital rubella syndrome" (CRS) Body weight below 2.5 kg, stunting; systemic organ damage after birth, congenital heart disease, deformity, deafness, blindness and so on. CRS in children is the most common eye diseases such as cataracts, followed by deafness, 60% of cardiovascular system defects. Surveys show that compared with pregnant women who have not been infected with rubella virus, their stillbirth and spontaneous abortion are two to four times higher. According to statistics, rubella virus infection within 1 month of pregnancy, the incidence of congenital malformations in infants was 33%, 25% within 2 months, 9% within 3 months, 4% within 4 months [3] , 5 months still have congenital deafness fetus born, 6 months pregnant other than rubella virus infection basically no risk of fetal deformity. The positive rate of pregnant women with acute infection is 0.2 ~ 13%, different regions, different seasons statistically significant difference. According to the low infection rate of women of childbearing age in our country, appropriate methods should be adopted to protect a few young women who are susceptible to the disease. If the RV-IgG antibody is negative before marriage check-up, the rubella vaccination should be gradually implemented and the vaccination Prohibition of pregnancy within 2 months before and after the vaccine.

Herpes simplex virus (HSV) belongs to the Herpes virus family, divided into type I and type II, the main routes of infection through secretions and with close contact with susceptible people. Herpes simplex virus type I is mainly transmitted through the respiratory tract, skin and mucous membranes in close contact with the infection of the skin and mucous membranes and organs above the waist, such as causing inflammation of the mouth mucosa, nasal vestibule, conjunctiva, throat and herpes, around the mouth and mouth Herpes. Type II virus infects the lower parts of the waist and causes genital herpes, which spreads mainly through sexual activity and may be related to cervical cancer. Both type I and type II viruses can cause meningitis and skin herpes. Pregnant women infected with HSV can be placental transmission or genital tract infection caused by intrauterine infection, induced abortion [4], premature birth (spontaneous abortion or premature birth rate is uninfected pregnant women, 2 to 3 times), stillbirth (mortality 90%), deformity, the occurrence of deformities and early embryo Toxoplasma, rubella virus, cytomegalovirus infection caused by deformity similar to, such as small head, small eyeball, chorioretinitis, cerebral calcification, thrombocytopenia, etc., can also occur Heart and limb abnormalities, skin herpes and so on.