The Study On Diagnostic Value Of IgG Avidity And The Test Of HCMV DNA In The Body Fluid In The Diagnosis Of HCMV Infection

Objective:To study the HCMV IgG seropositive rate in women of reproductive age in Tianjin and discuss the relationship between HCMV infection and related factors including age, occupation, places of residence, education background and adverse pregnancy history. To detect the viral load of HCMV shedding in body fluid of women who are serologically positive by FQ-PCR. To diagnose HCMV primary infection via HCMV IgG Avidity index test and study the viral shedding in HCMV primary infection. To discuss the relationship between pregnancy outcomes and the FQ-PCR and HCMV IgG AI test and evaluate the diagnositic value.Methods:The blood sample and the details of related information of1812women of reproductive age who came to General Hospital of Tianjin Medical University for progestation counseling and medical check-ups during pregnancy were collected randomly. To test the specific HCMV IgG in the blood serum by ELISA and select477women who are seropositive of IgG randomly and detect the viral load of HCMV shedding in the peripheral blood leukocytes (PBL), urine and vaginal secretion of these women using FQ-PCR. To compare the positive rates of viral shedding in different body fluid and the relation of HCMV shedding and the pregnancy state. To test the specific IgM and IgG AI in blood serum samples and study the relation between primary infection and viral shedding in vaginal secretion. Following36pregnant women till delivery. Amniocentesis is operated on12pregnant women under informed consent to test whether there is intrauterine infection. If the babies are born, test the HCMV DNA in the cord blood or urine within two weeks after birth by FQ-PCR to diagnose congenital HCMV infection. And also test HCMV DNA in the maternal milk to see the viral shedding state in milk.Results:1. The positive rate of HCMV IgG was70.5%among the women of reproductive age in Tianjin.2. The positive rate of HCMV IgG is associated with occupation, education background and adverse pregnancy history. The positive rate is higher in women with low level of education than in those with high level (P<0.05). The positive rate is higher in medical worker than other occupations (P<0.05). The positive rate is higher in women who are pregnant than those are not (P<0.05). The positive rate is higher in women who had a history of adverse pregnancy than those did not (P<0.05).3. The positive rate of HCMV IgM is5.5%. The IgG AI lower than40%suggests primary infection and statistic in our research shows that the incidence of HCMV primary infection is10.1%. The positive rate of HCMV DNA detected in PBL, urine and vaginal secretion of477women are2.5%、9.0%、19.1%respectively(x2=72.51,P=0.000).5. With the progress of pregnancy, the positive rate of HCMV DNA tested in PBL and vaginal secretion has an upward tendency.6. There are more primary infection in women who are IgM seropositive than those are negative.(26.9%vs9.1%, P<0.05).7.66.7%of women who are both IgM and HCMV DNA positive are HCMV primary infection while6.3%of women who are both IgM and HCMV DNA negative are primary infection(P<0.05). There are more HCMV DNA positive result of vaginal secretion in Women with primary infection than with non-primary infection(35.4%vs16.6%, P<0.05).8. The incidence of HCMV intrauterine infection is higher in primary infection than in non-primary infection.9. Women with high load (>104) HCMV shedding in vaginal secretion during the first trimester of pregnancy have a significant higher risk to get adverse pregnancy outcomes than those without,(RR=6.00). There are also correlations between HCMV shedding in vaginal secretion during the third trimester of pregnancy and viral shedding in maternal milk after birth (r=0.61).Conclusion:The HCMV infections are common in women of reproductive age. In Tianjin the positive rate of HCMV IgG was70.5%. HCMV infection is associated with occupation, education background and adverse pregnancy history. HCMV DNA can be tested in body fluid when active infection happens. The positive rate of HCMV DNA detected in vaginal secretion is higher than in PBL and urine. The primary infections cause more intrauterine infections and congenital HCMV infections. There are correlations between high load (>104) HCMV shedding in vaginal secretion during the first trimester of pregnancy and adverse pregnancy outcomes. As a result, conbining HCMV IgG AI with FQ-PCR in diagnosing HCMV infection during pregnancy can decrease the incidence of congenital HCMV infection to some extent and of big diagnositic value.