Vaginal yeast infection is a mycosis of the vaginal mucosa that occurs when it is colonized by strains of yeast-like Candida fungi. In the acute stage, there is redness, swelling and itching of the vulva; soreness, burning and itching in the vagina; abundant, curd-like discharge from the genital tract; in the chronic – dryness and atrophy of the mucous membrane, excoriation, pronounced lichenization. The diagnosis is established according to the clinical picture, microscopic and cultural studies. In case of vaginal yeast infection, systemic and local antimycotic agents, multivitamins, immunostimulants are prescribed.
Vaginal yeast infection, or thrush, is a type of vaginal fungal infection, the causative agent of which is microscopic yeast-like fungi of the genus Candida albicans (Candida albicans). Candida infection is of great importance in obstetrics and gynecology due to the widespread and increasing incidence in recent years. Among vaginal infections, candidiasis ranks second after bacterial vaginosis. Vaginal candidiasis usually affects women of childbearing age (pregnant women – 2-3 times more often), before the onset of menarche and in postmenopause it is rare. Yeast infection of the vagina can exist in the form of asymptomatic candidiasis and true vaginal candidiasis – acute (lasting up to 2 months) and chronic recurrent (lasting more than 2 months).
Vaginal yeast infection is caused by conditionally pathogenic yeast-like fungi of the genus Candida, living on the skin and mucous membranes of the oral cavity, gastrointestinal tract, external genitalia and vagina of healthy women. The change of growth phases (pseudomycelia and blastospores) gives fungi the opportunity to survive in a wide temperature and acid range. The death of candide causes boiling for 10-30 minutes, treatment with formalin, copper sulfate, carbolic and boric acid. The presence of a mannoprotein shell and enzymes (proteinases and catalases) in fungi makes it easier to resist the immune system of the macroorganism.
The dominant pathogens (in 75-80% of cases) are strains of C. albicans, which have a great pathogenic potential. Disease caused by other species (C.glabrata, C. tropicalis, C. krusei, C. parapsilosis) is more typical for certain ethnic groups (representatives of the African race) and geographical areas (the Mediterranean coast, the Middle East), which is associated with the specifics of the microbiocenosis of mucous membranes and skin, nutrition and living conditions.
As a rule, vaginal yeast infection is an endogenous infection that develops in conditions of asymptomatic candidiasis, usually vaginal, less often – on the oral mucosa, intestines and skin. For example, the recurrent form of vaginal candidiasis is caused by the persistence of candida in the intestine and the periodic entry of the pathogen into the vagina and its colonization. With vaginal candidiasis, pseudomycelium candide usually penetrates only into the superficial layers of the vaginal epithelium, less often affects deeper tissues with subsequent hematogenous spread and damage to various organs.
The appearance of vaginal yeast infection is facilitated by the insufficiency of the host body’s protective system, manifested by a decrease in the local immunity of the vagina. Local immunodeficiency against candida antigens (decreased activity of macrophages and lymphocytes) does not allow blocking fungal receptors and enzymes.
The disease is usually not accompanied by a noticeable decrease in the level of lactobacilli and a change in the normal vaginal microflora; but with the formation of polymicrobial associations, it can be combined with bacterial vaginosis.
The development is caused by a violation of the balance of sex hormones during pregnancy, taking hormonal contraceptives, endocrine pathology. The effect of fluctuations in estrogens and progesterone on the vaginal mucosa is manifested by an increase in the concentration of glycogen in epithelial cells, stimulation of their sensitivity to candida and more effective adhesion of fungi. Vaginal candidiasis is much more often accompanied by various conditions associated with immunosuppression (HIV infection, diabetes mellitus, tuberculosis, hypovitaminosis, excessive use of antibiotics, corticosteroids, cytostatics, radiation therapy, etc.). Vaginal candidiasis can be associated with atopic manifestations (allergic rhinitis, food allergies).
Nutritional errors, the use of hygiene products (pads, tampons), wearing tight clothes are not considered significant factors in the development of vaginal candidiasis. There is a possibility of transmission of candida infection to a newborn when passing through the birth canal of a sick mother; sexual infection is possible; the risk of infection is higher with frequent oral-genital contacts.
Symptoms of vaginal yeast infection
With candidiasis, there are no clinical manifestations, patients, as a rule, do not complain. With acute vaginal candidiasis, there are abundant thick white-gray discharge from the vagina, a curd-like appearance with a sour smell. The mucous membrane affected is swollen, hyperemic and prone to bleeding. Sharply delimited or merging with each other rounded and oval foci of curd plaque and films, ranging in size from point to 5-7 mm in diameter, are noted on it. In the acute phase, the deposits are tightly attached to the mucosa and are hardly cleaned off with the exposure of a shiny eroded surface with a scalloped edge; later they are easily removed, standing out from the genital tract. Typical for vaginal candidiasis is itching and burning in the vulva, which increases during menstruation, after physical activity, and water procedures. Patients are also concerned about sharp painful sensations during sexual intercourse.
With chronic vaginal candidiasis, the absence of characteristic secretions is possible, there is a slight hyperemia of the mucous membrane, scanty films and dry erosions, pronounced lichenization and excoriation. The mucous membrane becomes flabby, atrophic, the entrance to the vagina narrows, hemorrhagic rashes may appear.
The chronic form has a long long-term course.
Disease usually spreads to the external and internal genitalia, the urethra with the development of candidiasis vulvovaginitis, cervicitis and urethritis. Vaginal candidiasis can cause termination of pregnancy (spontaneous miscarriage, premature birth), development of endometritis in the postpartum period, infertility.
Diagnosis of vaginal yeast infection
The diagnosis is confirmed by the presence of clinical signs of infection and the isolation of fungal culture from the vaginal mucosa during microbiological examination. Examination of the cervix and vagina with the help of mirrors reveals hyperemia, swelling of the mucous membrane, gray-white curd deposits in its folds. When stained with Lugol’s solution, fine-point inclusions and a pronounced vascular pattern appear. Discharge with vaginal candidiasis is detected in about 76% of cases, itching – in 32%.
Microscopic examination of the smear determines round-oval, budding cells in places. When bakposev on Saburo medium, convex shiny white colonies of rounded shape are found. Species identification of fungi and determination of their sensitivity to drugs, complex PCR diagnostics and ELISA for STI pathogens are carried out. If necessary, the examination is supplemented with a bacteriological examination of urine and a smear of the urethra for microflora, analysis of feces for dysbiosis, determination of blood sugar, ultrasound of the pelvic organs, abdominal cavity and bladder.
Treatment and prevention of vaginal yeast infection
Complex treatment of vaginal yeast infection includes exposure to the pathogen – Candida fungi, elimination of provoking factors, therapy of concomitant pathology.
In vaginal candidiasis, various groups of antifungal agents are used systemically and topically: polyene antibiotics (nystatin, natamycin), antimycotics of the imidazole and triazole series (clotrimazole, ketoconazole, fluconazole, itraconazole). Good results in the treatment of vaginal candidiasis are shown by fluconazole, which has a wide spectrum of fungistatic action, which does not give a side effect on the synthesis of steroids and metabolism. The effectiveness of a single high-dose oral administration gives an advantage over other antimycotics.
With a mild course, local drugs (miconazole, clotrimazole) are indicated in the form of cream, vaginal candles and tablets. In case of chronic infection, systemic antifungal drugs are repeated in certain courses. It is preferable to prescribe low-toxic forms of antimycotics to pregnant women (natamycin, nifuratel intravaginally) and in childhood (nifuratel in applications and intravaginally, fluconazole orally).
Therapy can be supplemented with the local use of disinfectants and anti-inflammatory agents – borax in glycerin, potassium permanganate and silver nitrate in the form of baths and douches. In case of vaginal candidiasis of polymicrobial genesis, combinations of antimycotics with metronidazole are prescribed.
The correction of immunity with immunostimulating agents is carried out, the intake of multivitamins is indicated. The cure of vaginal candidiasis is determined by the disappearance of clinical signs and a negative result of microbiological examination.
Prevention of vaginal yeast infection consists in eliminating the conditions for its development: limiting the intake of COCs, antibiotics, cytostatics; drug correction of immunodeficiency, endocrinopathies and other concomitant pathology, preventive examination of women by a gynecologist.