Bacteriological and virological examination with habitual miscarriage of pregnancy
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Analysis of literature data and work experience of the department allows to draw a conclusion about the high importance of bacteriological and virological examination of patients with habitual miscarriages. According to research, persistent bacterial and viral infection is one of the main factors of miscarriage. Even in the absence of direct specific effect of infectious agents on the fetus, reproductive system disorders caused by their persistence in the endometrium, with the development of chronic endometritis, as well as concomitant endocrinopathies and autoimmune disorders, lead to disruption in the development of the embryo and fetus and to the termination of pregnancy.
A characteristic feature of endometrial microcenoses in patients with miscarriage is the presence of obligatory anaerobic microorganisms in them, and in case of miscarriage of pregnancy as an undeveloped pregnancy, the persistence of associations of viruses: herpes simplex virus type II, cytomegalovirus, Coxsaki A and B, etc.
For microbiological examination, the contents of the vagina and cervical canal are taken with a sterile cotton swab, which is then placed in a sterile tube. The collected material is sent to the bacteriological laboratory in the next 2-3 hours. Species identification of conditionally pathogenic microorganisms is carried out according to generally accepted methods. At the same time, the sensitivity of all isolated cultures to susceptibility to antibiotics is determined.
If it is necessary to take the endometrium for bacteriological and morphological examination, take it with a special curette or vacuum suction catheter on the 5th-6th day of the menstrual cycle with the precautions necessary to not mix the samples obtained from the uterine cavity and the cervical canal and only after determining that in the cervical canal has no pathogenic flora.
Simultaneously with the bacteriological expedient, a bacterioscopic examination of the genital tract to be separated. For a bacterioscopy, swabs from the cervical canal, posterior vaginal vault and urethra are taken on two glasses. The first smear is stained by Gram to exclude vaginosis in the first place, gonococcal infection; the second - staining by Romanovsky-Giemsa for the detection of trichomonads. The data of bacterioscopy of the reproductive genital tract help to determine the qualitative composition of microbial flora, the number of leukocytes, the composition of epithelial cells, which may to some extent characterize the severity of the inflammatory process.
If a urinary tract infection is suspected, a bacteriological examination of the urine is indicated. To do this, after the toilet of the external genitalia, a medium portion of urine (without a catheter) is collected in a sterile tube.
The tube is tightly closed with a stopper. One to one ml of urine is sufficient for the study. Bacteriuria is considered true if there are 10 5 or more colony forming units (CFU / ml).
To identify the chronic inflammatory process of the kidneys simultaneously with the bacteriological study of urine, it is advisable to conduct a urine test according to Nechiporenko. To do this, after the toilet of the external genitalia, an average portion of morning urine in an amount of at least 10 ml is collected in the test tube. The presence of an inflammatory process is indicated by the detection in the urine of more than 2500 leukocytes and more than 1000 erythrocytes.
Diagnosis of a persistent viral infection should include evaluation of the antigen or antigens themselves and an objective response of the organism to these antigens. If only viruses (antigens) are detected by any method, this will not be enough for diagnostics, since the case of transient passage of viruses without affecting the organism is possible. In addition, there may be a period of remission, when there are no viruses in the cervical channel, but the fact of a virus carrying can be. If you determine only antibodies to viruses, this is also not enough. The presence of antibodies to IgG viruses means that the body has already met this type of virus in the past and there is a response in the form of antibody formation. This is very important in obstetric practice, since it means that there will be no primary viral infection in the pregnant woman, namely this infection is most dangerous for the fetus. Secondary infection, i.e. Reactivation of a viral infection is less dangerous for a fetus and even in case of a disease it will proceed in a lighter form than with a primary infection.
The most informative methods for a clinician:
- The degree of viruses is the determination of viruses in urine sediment cells, indirect immunofluorescence (RNIF).
Based on the results obtained in RNIF, the morphometric indicator of the activity of a viral infection is determined. This takes into account the intensity of specific luminescence and the relative number of cells containing the viral antigen. The evaluation is carried out in a point system from "0" to "4+", in which practically the whole field of vision is covered by cells with bright granular and diffuse specific luminescence.
- The DNA probe method, DOT-hybridization, is the detection of viruses in the mucus of the cervical canal. This method is accurate for pathogens. For conditionally pathogenic microorganisms and persistent viruses, its significance is less and the cost is higher than when assessing the virus.
- Polymerase chain reaction (PCR diagnostics) is a highly sensitive method for determining antigens in acute and chronic forms of infection. As a clinical material, scraping of epithelial cells of the cervical canal is used. Using the method of PCR diagnostics, the presence of herpes simplex virus, cytomegalovirus, chlamydia, mycoplasma, ureaplasma in the cervical canal cells.
- Determination of antibodies to viruses, especially the presence of IgG. The presence of IgM antibodies is less informative, they quickly disappear, or on the contrary, persist for a long time. If suspected of reactivation, IgM antibodies are also examined.