RU2121687C1 - Method of predicting fetal infection in the latter half of pregnancy - Google Patents

Abstract

FIELD: obstetrics and gynecology. SUBSTANCE: one-fold low-invasive investigation of cervical mucus is performed by determining level of secretory immunoglobulin A and lysozyme activity in the mucus. When sum of products of these parameters by coefficients -0.11 and +8.6, respectively, and constant equal to 1.86 exceeds 1.0, probable fetal infection is predicted; when above-defined sum is below 0.9, emergence of this complication is regarded as unlikely; when between 0.9 and 1.0, pregnant is regarded as being in fetal infection risk group. EFFECT: reduced expenses and procedure duration. 2 ex

Description

 The present invention relates to medicine, namely to the immunological aspects of obstetrics and neonatology.

 The prior art.

The prototype of this invention are:
1. The method described in the domestic literature for the quantitative determination of secretory Ig A (SIg A) using radial gel immunodiffusion proposed by Manchini et al. in 1965 [1]. This method, being, according to the authors, quite highly informative, has several disadvantages. As a rule, it is used to determine the state of local immunity in the presence of an inflammatory process in the body. The immune status is influenced by many factors, and its isolated indicators are non-specific, are uninformative. In addition, the results are taken into account by visual observation, which introduces elements of subjectivity in the interpretation of the data obtained, thereby reducing their reliability.

 2. The method of rapid diagnosis of the inflammatory process of the female genital area, proposed by A.V. Kazakov et al. in 1990 [6]. The method is based on determining the activity of lysozyme of cervical mucus, as one of the factors of nonspecific defense of the body, and is intended to increase accuracy in the diagnosis of inflammatory processes of female genital organs. The disadvantage of this method is that an isolated determination of lysozyme activity is uninformative and requires additional research to select treatment tactics.

 Analogs of the proposed method are microbiological (bacteriological, bacterioscopic) and immunological studies described in the literature, aimed at detecting infectious pathogens in the female genital organs (Order No. 535 of April 22, 1985) or antibodies formed as a result of their introduction. These studies use very expensive media and immunological reagents. In addition, their production requires significant time (5 - 7 days). All of the above does not allow widespread use of the described methods for screening examination of pregnant women, with the aim of timely diagnosis of chronic intrauterine infection in them and prevention of fetal infection.

 SUMMARY OF THE INVENTION

 The purpose of the invention is to develop a method for predicting intrauterine infection of the fetus from the end of the 2nd trimester of pregnancy (from 28 to 30 weeks), which will allow timely treatment measures to be taken to prevent this complication. The method is based on a one-stage minimally invasive sampling of cervical mucus, quantification of SIgA in it by means of radial immunodiffusion in a gel (Manchini 1965) and determination of lysozyme activity (A.V. Kazakov et al. 1990) in a gestational age of 28-30 weeks.

In the mathematical processing of research data, a decisive rule was deduced for predicting intrauterine infection of the fetus
S = ML • K1 + SIgA • K2 + const,
Where
ML is an indicator of cervical mucus lysozyme activity (average diameter of growth retardation in Micrococcus Lisodeiticus test culture).

 SIgA is a quantitative measure of SIgA in cervical mucus.

K1; K2 - coefficients, with:
K1 = -0.11; K2 = 8.6; const = -1.86.

 It was further established that at S> 1.0, a reliable conclusion can be made about the likely intrauterine infection of the fetus, at S <-0.9, with the same degree of certainty, a conclusion can be drawn that there is no risk of intrauterine infection of the fetus. At -0.9 <S <1.0, pregnant women are at risk for this complication. Such patients need additional examination and dynamic observation. Our proposed method for predicting intrauterine infection of the fetus gives the probability of a correct prognosis in 77% of cases, with a significance level of P = 0.05. In addition, the method allows one to identify borderline states at the risk group level.

 The claimed method is used in patients.

 Example 1. Kulikova Yu. V., 25 years old. A history of one medical abortion. This pregnancy is the second. In the gestational age of 30 weeks, a survey was conducted according to the proposed methodology. Received S = 1.36, i.e. the probability of intrauterine infection of the fetus was revealed, about which a comprehensive antibacterial therapy was carried out. Pregnancy ended with an urgent birth, a girl was born weighing 3200 g, 51 cm long, with an estimate of w. Apgar 8 - 9 points without signs of intrauterine infection. The early neonatal period proceeded physiologically.

 Example 2. Shershneva VV, 25 years. A history of one spontaneous miscarriage at 12 weeks of gestation. This pregnancy is the second. In the gestation period of 29 - 30 weeks, a survey was conducted according to the proposed method. Received S = 1.38, i.e. the probability of intrauterine infection of the fetus was identified. Sanitation of the infection failed due to intolerance of the woman to antibiotics. Pregnancy ended with an urgent operative birth. A girl was born weighing 2900 g, length 50 cm, with an estimate of w. Apgar 6 - 7 points. The early neonatal period was complicated by the manifestation of conjunctivitis and catarrhal omphalitis.

 Thus, our proposed method for predicting intrauterine infection of the fetus by a single minimally invasive cervical connection, examining the SIgA level and lysozyme activity in it allows timely prevention of this complication. The method can be proposed for widespread use in obstetric practice.

Sources of information
1. Mancini G., Carbonara AO, Hermans IF Int. I. Immunochem., 1965, v. 2, p. 235.

 2. German G.P., E.V. Chernokhvostova et al. Quantitative determination of the level of immunoglobulins. // Journal of Microbiology, Epidemiology and Immunology. - 1971, N 12. - S. 62 - 67.

 3. Govallo V.I. Immunology of reproduction. 1987. Moscow. "The medicine".

 4. Taranov A. G. Radioimmune and enzyme immunoassay methods of analysis. // Laboratory diagnostics. - 1995.- S. 72 - 75, 98 - 102.

 5. Order N 535 of April 22, 1985 "On the unification of microbiological (bacteriological) research methods used in clinical diagnostic laboratories of medical institutions." Section 1. 9. Microbiological methods for the study of discharge from the female genital organs. Moscow. 1985.

 6. Kazakov A. V. et al. The method of rapid diagnosis of the inflammatory process of the female genital area. // Patent N 2009200. of March 15, 94. Priority of the invention from 5.02.90.

Claims (1)

 A method for predicting intrauterine infection of the fetus in the second half of pregnancy by determining the level of secretory immunoglobulin A, characterized in that a single minimally invasive study of cervical mucus is carried out, in which the level of secretory immunoglobulin A and lysozyme activity are determined, and with the value of the sum of the products of these parameters by factors of -0 , 11 and +8.6 and a constant equal to -1.86, exceeding 1.0, predict the fetal infection likely, if the value of the sum less than -0.9, construct the absence of the likelihood of this complication, and with an amount of less than 1.0, but more than -0.9, a pregnant woman is classified as a risk group for intrauterine infection of the fetus.