Although TORCH syndrome can cause a mild illness in women, intrauterine infections during pregnancy can lead to serious complications in the fetus. Therefore during pregnancy and at childbearing age, serological tests (titers of both IgM and IgG antibodies) are recommended to screen and prevent congenital malformations[24].
There is little data on the prevalence of TORCH infections among pregnant women in different geographic areas. Because the primary infection with TORCH syndrome is asymptomatic, therefore it is vital to identify the suspected women and prevent congenital problems [21, 22, 25]. This study aimed to investigate the prevalence of TORCH syndrome in women of reproductive age in Mashhad and discuss whether the TORCH is related to age or not.
As shown in figure 2, these graphs have not changed significantly with age. Therefore, with age, no significant changes are seen in the prevalence of TORCH syndrome (with three factors: T. gondii, CMV, and RV).
In our study, the specific IgG antibodies were found to be positive in for CMV in 402 cases (96.4%), for RV in 394 cases (94.5%), and for T. gondii in 80 cases (19.2%). Moreover, 7 (1.6%) of them were found to be positive for anti-CMV IgM, 6 (1.4%) for anti-IgM RV, and 8 (1.9%) for anti-IgM T. gondii. Furthermore, all the patients (100%) were proven negative for anti-IgM and IgG HSV. The seropositive rates of IgMs and IgGs antibody in the TORCH syndrome are shown in Table1.
The risk of transmission with T. gondii in the first, second, and third Trimester of Pregnancy is 15%, 30%, and 60%, respectively. However, the disease severity seems higher is higher in early pregnancy [26].
The seroprevalence of T. gondii is prevalent in tropical countries and in areas where raw or semi-raw meat is consumed [6, 27, 28]. For example, in India, the prevalence of anti- T. gondii IgG in women of reproductive age has been reported between 25 to 28% [29, 30].
In our study, 1.9 % of cases were positive for the IgM T. gondii, and 19.2% for IgG T. gondii.
In a study, the prevalence of antibodies against T. gondii in Brazilian women 53.03% for IgG and 3.26% for IgM, indicating the relationship between infection during pregnancy and climate, geographic, and socio-economic characteristics of this country[31, 32]. After That, in China, the prevalence of this infection was high due to their specific dietary habits [33]. In women Turkish has been reported for IgG T. gondii (26%) [34] and 52.1% while 0.54% of the cases were positive for anti-T. gondii IgM[35]. Studies show the reduction of toxoplasmosis prevalence in Western countries[36].
Fortunately, in this current study and reports from other areas of Iran, the prevalence of this infection was reported low.
In our study, according to the results, the relationship between age and T. gondii IgG was significant (P-value = 0.00, P <0.05), T. gondii IgG in the age group of 37-47 years is 6.44 times higher than the age group of 17-27 years.
CMV is the leading cause of congenital infections all over the world [37]. In developed countries, the prevalence of CMV IgG in pregnant women ranges from 40 to 60 percent. However, it exceeds 95 percent in developing countries (40), indicating the high exposure of these people to CMV. Recent research suggests that the majority of CMV infants are born from women who have anti-CMV IgG. As a result, it is critical to diagnose cytomegalovirus in women of childbearing age to prevent fetal defects[38].
In one study, the prevalence of anti-CMV IgG among women of reproductive age was reported to be about 65% that increased with age [39]. In women Turkish of childbearing age, the serum prevalence for anti-CMV was reported (99%)[34, 35, 40]. Also, the high prevalence of anti-CMV has been reported from Mexico, Brazil, and China.
In our study, the anti-CMV IgG was the highest. Also, the relationship between age and anti-CMV IgG was significant (P-value = 0.03, P<0.05); CMV IgG in the age group of 27-37 years was 4.13 times higher than the age group of 37-47 years. Similar studies in Iran have yielded the same results.
In a study in Kashan, the anti-CMV IgM was reported high, followed by anti-RV and -T. gondii [41]. In another study in Gorgan, 3.41% of mothers were negative or borderline for CMV antibodies, indicating that they can susceptible to CMV infection during pregnancy, as Intrauterine and prenatal infection with CMV can infect 9.5 % to 22% of newborns[42].
Interestingly, two studies conducted by health authorities in the United Kingdom and Japan concluded that only CMV antibodies testing was sufficient in maternal serum[43, 44].
Although, RV infection is a harmless dermatitis disease in childhood, during pregnancy (especially in the first 12 weeks) can result in congenital rubella syndrome (CRS), severe birth defects, and miscarriage[45]. One study found that the prevalence of RV antibodies increased from 93% to 98% in Brazilian women[32]. The prevalence of anti-RV IgG was also high in Turkish women (94%)[34, 35]. On the other hand, the anti-RV IgM in this study was 94.5%, suggesting vaccination in pregnant women to prevent RV infection.
A similar study in Bandar Abbas reported that 13% of women of childbearing age had anti-RV, therefore, vaccination was strongly suggested in premarital girls[46].
In our study, the rubella IgG rate was 94.5%, and no found a correlation between age and RV infection.
Studies show that there is a high prevalence of this infection in women of reproductive age worldwide. Therefore, the World Health Organization (WHO) recommends that countries introduce and use Rubella-containing vaccines (RCV) to reduce RV infection and congenital rubella syndrome (CRS). Analyzes show that the use of extensive vaccination will significantly reduce the amount of rubella.
Limitations:
Our study was conducted on a limited number of samples and only in the city of Mashhad. Also, unfortunately there were very little laboratory data about HSV infection as one of the pathogens of TORCH syndrome. Expanding this study throughout the country and understanding the main causes of this syndrome in Iran, will help to alleviate concerns about the percentage of congenital defects with infectious causes.