Genital candidiasis
Introduction
Introduction to genital candidiasis Genital candidiasis is a common mucosal candidiasis caused by Candida albicans infection, which can affect both men and women. In men, it is manifested as Candida balanitis, which occurs in people with too long prepuce. In women, vulvovaginal candidiasis occurs in women of childbearing age, and the increase in genital itching and vaginal discharge is the main manifestation. basic knowledge The proportion of illness: 0.0008% Susceptible people: good for young people Mode of infection: contagious Complications: vulvitis erythema diabetes recurrent vulvovaginal candidiasis
Cause
Causes of genital candidiasis
Bacterial infection (60%):
Candida is a conditional pathogen. Whether it occurs after invading the human body depends on the level of human immunity and the number and virulence of the infected bacteria. When the human body is pregnant, diabetes, oral contraceptives, long-term application of broad-spectrum antibiotics, corticosteroids and immunosuppressive agents to reduce the body's immunity and change the environment of the vagina, it is easy to induce Candida infection.
Candida albicans infection first adheres to the epithelial cells of the host and then forms an infection in the presence of the pathogenic factors of Candida albicans described above. Adherence to epithelial cells is due to the adhesion receptors of Candida albicans on the surface of the host cell membrane, namely fucose and N-acetylglucosamine; a variety of adhesion mediators on the cell wall of Candida albicans are important. There are mannans - protein complexes (MP) and chitin. Chitin is a stereogenic multimer of (1-3, 1-6) -glucan and N-acetylglucosamine; the cell wall of Candida albicans has fibrinogen, fibronectin and other components. Adhesive receptor. These components are widely distributed in the blood vessel wall, inflammation and wound healing, and have strong adhesion. When they are adhered to Candida albicans, they can bridge the adhesion between Candida albicans and host cells, making Candida albicans easier. Adhere and invade the host.
The virulence of Candida is related to the following factors:
Adhesion
Adhesion is directly proportional to virulence, and Candida albicans has the strongest adhesion in Candida.
2. Two forms
When infected, Candida albicans is often hyphal. The virulence of the mycelium type is stronger than that of the yeast type.
Toxin
The polysaccharide toxin on the surface of bacterial cells and another known as "candida toxin" may be a causative factor.
4. Cell surface composition.
5. Extracellular enzymes
Candida albicans can produce certain enzymes, such as lysophosphatidase, phospholipase and extracellular acid protease (CAP). Among them, CAP is the most important. CAP not only hydrolyzes proteins, but also hydrolyzes keratin and collagen, and promotes the adhesion function of Candida albicans.
Other factors (10%):
Wearing tight-fitting underwear, vaginal lavage, etc., in men, long-term changes in hormone metabolism, diabetes, long-term use of antibiotics or glucocorticoids can lead to changes in the body's immune function, causing Candida infection in the foreskin glans.
Pathogenesis
Candida is a conditional pathogen, and the decline of the body's resistance is the internal cause of the disease. The virulence or pathogenicity of Candida is an external cause.
The balance between Candida, vaginal flora and vaginal defense mechanisms determines different clinical manifestations, and the predisposing factors for vulvovaginal candidiasis include:
1. Apply a large number of broad-spectrum antibiotics.
2. Pregnancy.
3. Apply high-estrogen content oral contraceptives.
4. Diabetes.
5. Receive immunosuppressive therapy and HIV infection.
6. Other
Prevention
Genital candidiasis prevention
1. Keep the genital area clean, wash frequently, change underwear frequently, keep it dry locally, and avoid topical steroid corticosteroids.
2. Take a shower and take a shower to avoid bathing.
3. The spouse or partner of the patient should be examined together, treated, avoiding sex during treatment, and not engaging in extramarital sex.
4. Actively prevent the predisposing factors mentioned above.
Complication
Genital candidiasis complications Complications vulvitis erythema diabetes recurrent vulvovaginal candidiasis
Mainly female Candida vaginitis, because the secretion of the vulva stimulation, plus secondary infection, causing Candida vulvitis, at this time, the size of the labia, yin, genital area around the vulva and the inside of the thigh, erosion, surface There are moist white scales, blood papules, small blisters, etc. around the erythema, there is obvious itching sensation, VVC with complications refers to recurrent vulvovaginal candidiasis, clinical symptoms are more serious, can be caused by Candida albicans Other Candida causes, often accompanied by diabetes, immunosuppression or pregnancy.
Symptom
Symptoms of genital candidiasis common symptoms vaginal discharge increased sexual intercourse difficulty white lochia pimples skin hypertrophy itchy scaly urinary frequency urinary pain pustules
Candida foreskin balanitis: more common in the foreskin is too long, there is a history of unclean sexual intercourse, penis foreskin, glans mild flushing, foreskin inner plate and glans crown can have white cheese-like patches, glans can have a needle size red Pimples, if the outside of the foreskin and the scrotum are invaded, scaly erythema can be seen. If the scaphoid nest is involved, there may be frequent urination, dysuria, etc. Local burning tingling and itching may occur. For those who have allergies to Candida, after unclean sexual intercourse Penile itching and burning sensation can occur in a few hours, and there may be flushing of the foreskin glans, occasionally fulminant edematous foreskin balanitis, mainly manifested by obvious edema of the penis foreskin, itchy, shallow ulcers.
Candida vulvovaginitis: vaginal itching and increased vaginal discharge are prominent manifestations of this disease, local itching, due to scratching, swelling of the labia minora, epidermal erosion, scratches and pustules, vaginal secretions are thick, cheese Sample or bean dregs, taste odor, and may have vaginal pain, irritation and difficulty in sexual intercourse, etc., check the vaginal wall mucosa on the white pseudomembrane, after detachment may have erythema or erosion surface, vaginal wall congestion and edema, some asymptomatic health Candida can be isolated from women's vagina, but does not necessarily cause vaginitis, pregnancy, oral contraceptives or antibiotics, diabetes or tightness.
1. Vulvovaginal candidiasis:
(1) The main symptoms are genital itching, burning pain, increased vaginal discharge, dysuria, pain or irritation in the vagina, and superficial sexual pain, genital itching is the most common symptom, almost seen in all symptomatic patients, light and heavy Unlike the typical vaginal secretions, which are white curd or bean dregs, they can also be watery or evenly viscous.
(2) physical examination showed vulvar flushing and edema, scattered in the scratch or epidermal exfoliation, chronic infection of the vulva skin hypertrophy was lichen-like changes, vaginal mucosa congestion, redness or erosion, white curd or bean dregs-like secretions in the vagina, vaginal wall Attached with a white film, the pH of the vaginal secretions is generally normal.
The symptoms of VVC relapse 4 or more times per year and are confirmed by pathogens, called recurrent vulvovaginal candidiasis (RVVC). About 5% of patients with VVC can develop RVVC. Currently, according to clinical manifestations, microbiology , host factors and response to treatment, VVC is divided into two categories of no complications and complications, uncomplicated VVC refers to sporadic VVC, the condition is mild to moderate, mainly caused by Candida albicans, the body's Good immune status, effective for conventional antifungal treatment, this category accounts for 90% to 95%, VVC with complications refers to recurrent vulvovaginal candidiasis, clinical symptoms are more serious, can be other than Candida albicans Caused, often accompanied by diabetes, immunosuppression or pregnancy.
2. Candida foreskin balanitis: diffuse flushing of the foreskin and glans, dry and smooth, red papules or white cheese-like patches on the medial and coronal sulcus of the foreskin. Frequent urination and dysuria may occur when the urethral scapula is involved. .
Examine
Examination of genital candidiasis
First, direct microscopic examination: women use a long sterile cotton swab to take the vagina, cervical secretions or milky white film on the vaginal wall, male scraping the penis glans, crown sulcus or foreskin surface lesions as the specimen to be examined, will be treated The specimens were prepared with 10% potassium hydroxide or physiological saline. Microscopic spores and pseudohyphae were observed under the microscope. If more pseudohyphae were found, it indicated that Candida was in the pathogenic stage, and the diagnosis was more Significant.
Second, staining examination: Gram staining, Congo red staining or PAS staining after microscopic examination, the positive rate is higher than direct microscopy, Gram stain, spore and pseudohyphae dyed blue: Congo Red and PAS stained, spores and pseudohyphae were dyed red.
3. Separation and culture: Patients with negative smear test can be cultured in Candida, and the test specimens are inoculated on Sabouraud medium under sterile conditions (used in vitro), and the test medium is slanted during inoculation. Cut a little, inoculate 2-3 per tube, inoculate 2 tubes per specimen, and incubate the medium in a 37 °C incubator for 24-48 hours. Observe a large number of milky white colonies and pick up a small number of colonies with the inoculation needle. Smear, direct microscopic examination or microscopic examination after staining, a large number of spores can be seen, which can be initially diagnosed as Candida infection.
4. Candida albicans antibodies can be detected by immunodiffusion or latex coagulation.
Fungal culture: Candida culture and identification and drug susceptibility testing may be considered in the following situations:
1. The clinical symptoms suggest VVC and the microscopic examination is negative.
2. Use of empirical treatment for uncomplicated VVC failure.
3. Prepare for long-term inhibitory antifungal treatment of patients with complications of VVC.
Diagnosis
Diagnosis and identification of genital candidiasis
Diagnose based on:
The clinical symptoms of genital candidiasis are various, so the diagnosis should be based on the corresponding clinical features combined with mycological examination. Since Candida is a resident resident of the human body, when the specimen culture is positive or only a few spores are seen by microscopy, only It shows that there is Candida, can not be diagnosed as candidiasis, only a large number of spores, pseudohyphae or hyphae can be seen in the microscopic examination, it can be said that the bacteria is in a pathogenic state, if necessary, pathological examination, found that fungal invasive tissue can be Make a diagnosis.
Vulvovaginal candidiasis
(1) Symptoms: Itching or irritation of the vulva, increased vaginal secretions.
(2) Signs: vulva redness and swelling, scattered in scratches or epidermal exfoliation, chronic infection of the vulva skin hypertrophy is lichen-like; vaginal mucosa congestion, redness or erosion, vaginal secretions are cheese-like clots or bean dregs.
(3) Laboratory examination: microscopic examination showed that pseudohyphae or blast spores were positive; Candida culture was positive.
A clinical diagnosis of vulvovaginal candidiasis can be performed in patients with typical vulvovaginal symptoms and signs; a clear diagnosis can be made for patients who also have any of the indicators in the laboratory test.
2. Candida foreskin balanitis
Clinically, there are related manifestations, especially white cheese-like patches or dense red papules in the foreskin and glans coronal sulcus. The disease should be considered. The laboratory should perform fungal microscopy and culture, and see yeast-like bacteria. Pseudo-hyphae or blast spores.
Differential diagnosis
The disease is mainly differentiated from trichomonas vaginitis and male non-gonococcal urethritis caused by trichomoniasis.
1. Trichomonas vaginitis: increased vaginal discharge is foamy, sometimes serous or purulent, stench, and may have urethritis, cystitis, cervicitis, paraurethral gland and pasteurized gland infection, even There are kidney and nephritis, dysuria, hematuria and nocturia, vaginal examination can be seen cervical congestion, vaginal wall congestion, edema, and bleeding points, a characteristic appearance of strawberry-like appearance, can be found vaginal Trichomonas.
2. Male non-gonococcal urethritis: symptoms are milder than gonorrhea, manifested as urinary tract itching, discomfort or dysuria, may have purulent secretions, can also cause cystitis, prostatitis or epididymitis, urethral secretions can be found Insects. Bacterial vaginosis has no irritating symptoms or signs of vulvitis, and vaginal secretions are thin and uniform.
3. Vulvar skin disease: Vulvovaginal candidiasis needs to be differentiated from eczema with genital itching or irritation, neurodermatitis, genital pruritus, lichen planus and other skin diseases. These skin diseases are only genital itching and/or Symptoms and signs of vulvitis, no vaginitis manifestations, vaginal secretions for fungal microscopy or culture negative.
4. Others: such as foreskin balanitis.
