Papillomaviruses (HPV, Latin abbreviation – HPV) – an extensive group of viruses, numbering about 150 strains and affecting epithelial tissues. Some subtypes of HPV are harmless, others are unpleasant, because they lead to the appearance of warts on the skin, but there are also life-threatening varieties.
Special fears among doctors are caused by those subspecies that cause degeneration of epithelial tissues, leading to the development of benign and malignant tumors.
The papilloma virus is easily transmitted through sexual contact. Today it is considered the second most common after a group of herpes viruses. Up to 70-75% of adults are carriers of it, and at least half of them have clinical manifestations.
As the study proceeds, virologists isolate strains of increased oncogenic risk that can cause cervical cancer, breast cancer (according to 2011) and other types of malignant tumors. The most dangerous strains are 16, 18, 31, 33, 35, 39, 45, 51, 52, 54, 56, 66, 68, 82 – they have a high risk of oncogenicity, cause precancerous conditions and cancer in women and men. In approximately 70% of women with severe dysplasia and cervical cancer, HPV 16 and 18 became the main provocateur.
Anxiety in doctors is caused by flat and genital warts, papillomas and neoplastic changes in the cervical epithelium that occur under the influence of HPV. If the doctor found such manifestations during a gynecological examination, he will certainly send the patient for examination and take an HPV test to find out if she is infected with a subspecies of high risk of oncogenicity.
The same analysis will need to be submitted to the man in the event of genital warts in the perianal region or on the genitals.
Why diagnose HPV
There are a lot of HPV strains, and a person can be infected with several of them at the same time, as well as be infected more than once. If he has clinical manifestations of HPV, for example, condylomas, then during sexual contact the virus will be transmitted to the partner. At the same time, short-term skin contact is sufficient, therefore, the use of condoms does not fully protect against HPV.
The incubation period lasts from a month to 5-10 years, and the clinical manifestations are far from always observed, or the infected person does not notice them. In approximately 90% of cases, healthy immunity suppresses the virus on its own, even without treatment.
But in some cases, the pathogen may linger in the body, then doctors talk about persistent infection. However, even it does not always lead to severe dysplasia or cancer. If condylomas, papillomas on the genitals or neoplasia of the cervix are detected, then these diseases are treated as independent, regardless of the results of HPV tests, which are used to assess oncology risks and control the strength of the immune response.
HPV tests: how often to take
Since women are at risk, HPV is especially dangerous for them; they are advised to be tested regularly. With the onset of sexual activity, approximately 70-75% of girls become infected with the HPV virus, which can be detected in tests (smear). In some cases, a slight ectopy of CMM is detected. Usually it requires only observation, and after a year – two HPVs are successfully suppressed, and ectopia disappears.
At age 21, according to modern standards, all girls, regardless of whether they live sexually, are recommended to undergo screening for CMM cancer (cytological examination, PAP test) and HPV analysis. If the latter is negative, and the cervix is normal, then in the subsequent cytology, before reaching 30 years, it is recommended to do it every three years, at the same time an analysis for papillomavirus (HPV screening) is given.
If HPV infection is present, especially if subtypes of the virus with high oncogenicity are detected, there are neoplastic changes in the CM epithelium, a PAP test and a gynecologist's examination are recommended to be performed once a year.
After 30 years of age, women are advised to undergo screening annually. It is believed that at a young age the virus is successfully suppressed, but over time, it is more difficult for the immune system to maintain protection. Plus, there is an increased risk of developing CMM cancer, which is extremely rarely diagnosed before age 30.
Possible indications for the analysis:
- Scheduled gynecological examination;
- Unprotected sexual intercourse or contacts with multiple partners during the period following a routine examination;
- Preparation for pregnancy;
- The presence of epithelial neoplasms on the genitals.
An unscheduled analysis can be prescribed for both a man and a woman with the following symptoms:
- Urination disorders (condylomas and papillomas can be localized in the urinary tract);
- Burning and itching in the genitals;
- Pain and discomfort during intercourse;
- Pain in the anus (condylomas are localized around the anus, in the rectum);
- Inflammation of the inguinal lymph nodes.
Examination of a woman begins with the usual appointment with a gynecologist. He conducts an examination, collects an anamnesis, is interested in complaints. At this stage, condylomas and papillomas can be detected.
During the examination, the doctor takes a smear for PCR HPV and a smear for cytology (Papanicolaou test, PAP test). Below we consider in more detail the essence of these studies. If the PCR result is positive, and changes in the epithelium of the CM are detected, the woman is sent for colposcopy – an instrumental examination to assess the status of the CM. About this study can be read below.
What does the PAP test show?
A method for examining cervical smears for pathologically altered cells was invented by a Greek doctor named Papanicolaou back in the 30s of the 20th century. And today, it remains the leading method of screening studies to detect precancerous conditions of CM and infection with PVI. As previously mentioned, WHO recommends that healthy women take it every three years.
It is believed that on average, a persistent papillomavirus infection caused by a highly oncogenic strain can degenerate into cancer in 10-15 years. Therefore, regular examinations protect the health and life of a woman.
Smears from the vaginal fornix, the surface of the cervix and cervical canal are taken with special tools and applied to a glass slide. Then this material is treated with a special composition so that the cell does not dry out and does not deform, and is stained according to the Papanicolaou method. Stained glass is sent to the laboratory for analysis.
Under a microscope, a specialist examines cells, analyzes their shape and size. According to the results of this study, a conclusion is given that relates the material obtained to one of five classes.
Table 1 provides a description of cytological classes:
Norm, there are no atypical cells.
There are cells that are changed as a result of inflammation of the mucosa, an inflammatory process, for example, caused by an STD, proceeds. After treatment, the smear usually returns to normal.
There are single atypical cells, it is necessary to clarify the diagnosis using other studies or repeat the test after 4 months.
Clearly altered cells have been detected, suggesting a precancerous condition or cancer.
A large number of altered cells were recorded.
In the last three cases, the woman will be sent for further in-depth examination, with class 2, the smear will need to be re-submitted after treatment for CM inflammation.
With papillomavirus infection, among atypical cells, coylocytes (cells that have an atypical bright zone around the nucleus and numerous vacuoles in the cytoplasm) and diskeratocytes (elements with an unusually large nucleus) are found.
Preparation and cost of the study
The PAP test gives the best results if it is carried out immediately after menstruation. 48 hours before the study, sexual contact should be excluded. You can not use medicines for the introduction into the vagina (suppositories, spermicidal contraceptives), do douching.
If there are signs of infection (itching, discharge), then they must first be cured, then conduct a test. The study itself is completely painless and lasts only a few minutes along with an examination.
The PAP test is done for free (according to the compulsory medical insurance policy) in any gynecology, but if you want to get the most accurate results, you can do thin-layer liquid cytology (a more advanced method) in a private clinic. The approximate price in Moscow clinics is 1,500 rubles.
Molecular biological research methods
The second part of the screening is the papillomavirus analysis itself. They are important because even with normal cytology, a positive molecular analysis says that a woman is at risk.
This includes two types of research:
- Polymerase chain reaction;
- Digene test
HPV PCR Analysis
PCR (polymerase chain reaction) detects the DNA of a virus in a biomaterial. There is a qualitative analysis – its result shows only the presence of one or another HPV group, but not the concentration of the virus in the body. The result of the analysis is “detected” or “not found”. It is used for screening.
Quantitative analysis already makes it possible to see the pathogen concentration per 100 thousand cells (total viral load) of highly oncogenic strains. This allows you to assess the risks to humans and track the effectiveness of treatment in control analyzes.
On the form of quantitative analysis there may be such indicators:
- Lg less than 3 – a virus in a clinically insignificant amount;
- Lg 3-5 – viral load is increased, there is a risk of malignant degeneration;
- L more than 5 is a very high level, the probability of degeneration is very high.
To determine the type of HPV, real-time quantum PCR studies are used. This is both a quantitative and a qualitative analysis. HPV Quantum 4 defines the 4 most oncogenic viruses – 6, 11, 16, 18. Quantum 15 and 21 cover the corresponding number of strains with medium and high oncogenic danger. Infection with several high-oncogenic strains at once requires a particularly attentive physician's attitude.
When infection with a highly oncogenic strain is detected for women over 30, genotyping is used – blood is taken for control tests (repeated once a year) to determine if the same strain circulates in the blood as before. A persistent infection will not disappear on its own and requires treatment, if the strain has changed, then this is another infection with which the immunity is most likely to cope.
For PCR analysis, scraping of epithelial cells is taken during a gynecological examination (first half of the cycle). The same test is carried out for men, if there is a suspicion of infection with HPV, only scraping is taken from the urethra. Sometimes men or women take blood or urine for analysis.
Preparing for PCR is simple: give up sex in three days. Women should not douche or wash with antibacterial soap the day before. Men – do not urinate an hour and a half before scraping.
The cost of such an analysis depends on the method of investigation. Since the method requires high-tech equipment, the price ranges from 1-3 thousand rubles.
Hybrid Capture Method Digin test
This is the most sensitive and informative of the existing tests for the human papillomavirus. It is both quantitative and qualitative, and determines the concentration of the virus and strain. Therefore, this analysis is used for both primary research and therapy control. For the study, different biomaterials can be used: a smear from the cervical canal, urethra, material taken for biopsy or cytology.
Typically, private clinics offer comprehensive identification of strains with both low and high oncogenic risk. All this together with a fence of material will cost about 6-7 thousand rubles. State clinics do not offer such a procedure as part of the compulsory medical insurance.
In-depth examination: colposcopy and histology
It is carried out with appropriate indications: if the cytology is bad, and / or infection with a virus with high oncogenicity is detected. During colposcopy, the vaginal part of the CMM is examined in detail with the help of sophisticated equipment – a special binocular microscope (colposcope) with illumination. This allows the doctor to see even minor changes in the epithelium. To get an accurate diagnosis, special optical filters are used.
With extended colposcopy, a test is carried out with a Lugol solution and 5% acetic acid solution. These samples help identify altered cells that are not visible. When using iodine, it does not stain as healthy, and when treated with vinegar, they turn white.
During the examination, the doctor decides whether a biopsy should be performed, and if so, from which site it is better to take the material, and in what way. For example, when revealing unpainted cells on a Schiller test (test with Lugol), tissues are taken from this area. A biopsy is also performed under the control of a colposcope. The biological material taken in this case is sent for histological examination in order to detect malignantly altered cells.
Histology, in contrast to cytology, uses biomaterial taken not only from the surface, but also from underlying tissues. This makes it possible to make an accurate diagnosis.
Men are also given a biopsy to identify genital warts on the skin or mucous membranes. Usually this manipulation is prescribed by a urologist or dermatovenerologist.
Preparation and cost of procedures
Colposcopy is performed in gynecological clinics, both public and private. Preparing for the procedure is not difficult: for 48 hours to abandon vaginal sex, the use of tampons, douching. Inspection by colposcope lasts 15–25 minutes. If any manipulations were performed with the cervix, there may be a slight spotting bleeding after the procedure, this is normal.
After a biopsy, it is recommended to refrain from sexual intercourse for 10 days.
How much does colposcopy cost? Simple is about two times cheaper than extended – from 1200 wheels in Moscow. The cost of a biopsy depends on the method used, on average it is 3000 rubles. At the same time, this procedure can be completed completely free of charge – according to the MHI policy. Where to do the examination, in a public clinic or private, the patient decides.