Papillomaviruses are a group of DNA-containing viruses that infect epithelial cells of organs and tissues: skin, mucous membranes.
What is the danger of HPV type 16 for women?
A characteristic feature of papillomaviruses is the ability to induce the formation of various epithelial tumors.
The forms of tissue damage caused by HPV are diverse. Asymptomatic and subtle: keratosis, dysplasia. There are clinically pronounced: warts, papillomas, condylomas. Most are absolutely safe. Without treatment, they remain a lifelong cosmetic defect or disappear on their own (self-healing).
But sometimes benign lesions can degenerate into malignant tumors – carcinomas.
- Carcinoma or epithelial cancer is a malignant tumor that develops from the altered epithelial cells of various tissues.
Today, it has been established that human papillomavirus infection is the leading cause of cervical cancer. In clinically expressed cervical cancer of HPV, high risks of oncogenicity are detected in 95-100% of cases.
About 100 serotypes of papillomaviruses are known. About 17 are considered oncogenic.
- The most at-risk groups include HPV types: sixteen, 18, 31, 33, 35, 39, 45, 46, 51, 52, 56, 58, 59 and 68.
- Low-risk viruses remain HPV types: 6, 11, 42, 43, 44.
For women, HPV 16 and 18 types are especially dangerous: they most often cause cervical cancer.
HPV 16/18 accounts for 70% of cervical cancer associated with human papillomavirus infection. Moreover, the most common squamous cell carcinoma is associated with HPV type 16. A rare glandular cancer – with HPV type 18.
Infection with HPV type 16
The prevalence of human papillomavirus infection is extremely high: the DNA of certain (sometimes several) HPV types are found in more than 80% of the adult population.
Mucosotropic HPV, including serotype 16, are referred to as sexually transmitted infections (STIs). The probability of infection through the blood, household items, the more airborne insignificant.
Ways of infection of HPV 16 type:
- Sexual path: traditional, oral, unconventional sexual contact with an infected partner.
- Intrauterine: infection of the fetus from an infected mother through the placenta or amniotic fluid.
- During childbirth: infection of the newborn when passing through the birth canal of the mother affected by warts.
What happens after infection with HPV type 16?
The overwhelming majority of infected HPV are unaware of the incident and have no further complications in the future.
Moreover, up to 75% of sexually active women throughout their lives are infected with different types of HPV several times. However, in 2/3 of women, the active infection after some time is partially or completely excreted from the body by the immune system.
The “remnants” of viruses are “preserved” in sensitive tissues in the form of HPV DNA and are inherited inside an infected cell clone throughout the carrier’s life. At the time of weakening of local or general immunity, latent HPV infection “wakes up”, recurs, manifests clinically.
Reasons for reducing immunity to HPV type 16 in women:
– pregnancy; – age-related changes associated with aging; – acute, chronic gynecological, somatic, inflammatory, infectious diseases; – STIs: chlamydia, genital herpes, CMVI, trichomoniasis, gonorrhea, syphilis, HIV, etc. – hormonal imbalance; – neuroendocrine, metabolic disorders, obesity; – operations, injuries, abortions, difficult childbirth; – chronic stress, physical exhaustion; – treatment with cytotoxic, immunosuppressive drugs; – aggressive insolation, ionizing radiation, radiation therapy; – Smoking, alcoholism.
A prolonged unproductive persistent course of HPV infection is possible only against the background of immunity defects.
Symptoms of HPV type 16 in women
- Latent infection – no symptoms.
The presence of the virus can only be detected using modern immunochemical or molecular-biological techniques that determine the presence of antigens or HPV DNA in the body.
In women, even the asymptomatic course of HPV 16 can initiate cervical cancer.
HPV infection persists (it sharpens, then subsides), proceeds unnoticed, against the background of chronic vulvogenitis, endocervicitis, cervical pseudo-erosion. Sometimes the patient is worried about burning, itching in the genital area. Scant anomalous vaginal discharge, dysuric phenomena are possible.
In cervical smears appear: coylocytes, leukocytes, abnormal cells; sometimes pathogenic flora (the combination of HPV infection with other STIs is quite natural).
What should be a smear from the vagina in a healthy woman in detail in the article: Elevated leukocytes in a smear in a woman – the reasons.
In the histological specimens of the cervical mucosa, pathological changes in the structure of the cervical epithelium are visible. When tumor transformation occurs dysplasia (neoplasia, CIN).
HPV infection in women is papillomatosis or condyloma of the vulva, vagina, cervix, anogenital area.
How to cure condylomas, how anogenital warts look – read in detail in the article: Peaked warts.
HPV 16 type and cervical cancer
The high-risk papillomaviruses include specific structural proteins oncoproteins E6 and E9. They are able to inactivate intracellular immunity. They are especially numerous in HPV 16 type. By causing genetic instability, oncoproteins of HPV 16 initiate cell mutation, the development of intraepithelial neoplasia, and cervical cancer.
Cervical dysplasia or cervical intraepithelial neoplasia (CIN / CIN) is a violation of the structure of the epithelial layers of the cervical mucosa. The pathological process is caused by abnormal reproduction (proliferation) of atypical, transformed HPV cells.
Cervical dysplasia is an early manifestation of human papillomavirus infection caused by HPV 16 and 18 types.
Moderate and severe dysplasia (CIN 2-3) is a precancerous condition. Without treatment by the age of 40-49 on the background of age-related changes in the immunity, it can malignize into clinically pronounced (invasive) cancer. Malignant degeneration progresses So slow, for years.
Timely detection and adequate treatment of CIN completely prevents the development of cervical cancer.
That is why every female sex worker should do a routine screening diagnosis of HPV and take a smear test for oncocytology (PAP test).
DNA diagnosis of HPV type 16 in women
The material for this study are: vaginal smear or cervical scraping.
There are two main molecular methods for detecting and verifying HPV serotypes:
1. PCR – polymerase chain reaction method.
Allows you to find a specific type of HPV in the test material. The PCR test is highly sensitive. It reveals even the minimum amount of viral genetic material. But! According to its results, it is difficult to distinguish the active infection process from the safe latent HPV carrier state.
Interpretation of the results of the PCR test for oncogenic HPV 16/18 types