Urogenital mycoplasma infection
Introduction
Introduction to genitourinary mycoplasma infection With the deepening of research work and the emergence of new selective media, new types of mycoplasma have increased. To date, the mycoplasma that causes human sexually transmitted diseases (STD) or parasitic in the human genitourinary tract has mycoplasmarealyticum, mycoplasmahominis (MH), mycoplasmage nitisol (MG), mycoplasma genus (mycoplasmapene trans, MPe), mycoplasmafermentans (MF), mycoplasmasalivarium (MS), mycoplasmaspermatophilum (MSp), and mycoplasma primatum (MPr). There is evidence that this type of mycoplasma (MH, MG) can cause human genitourinary infections and is a common pathogen of non-gonococcal urethritis (NGU). Can cause urethritis, male infertility, chronic prostatitis, epididymitis, salpingitis, pelvic inflammatory disease, vaginitis. Among them, Ureaplasma urealyticum is one of the important pathogens causing perinatal maternal-infant infection. basic knowledge The proportion of sickness: 0.01% Susceptible people: no special people Mode of transmission: sexual transmission, contact transmission Complications: endometritis, premature delivery, premature rupture of membranes
Cause
Causes of urogenital mycoplasma infection
(1) Causes of the disease
Seven of the 15 human mycoplasmas are more common in the genitourinary tract. An overview of genital mycoplasma and ureaplasma urealyticum is now available.
Genital mycoplasma
The appearance of Mycoplasma genitalium is in the form of a flask, 0.6-0.7 m high, 0.3-0.4 m wide at the bottom, 0.06-0.08 m at the top, and has a rod-like structure at the end. It does not grow in the general medium and is cultured in SP-4 without cesium acetate. Growth in the base, the optimum growth temperature is 37 ° C, can ferment glucose, can not decompose arginine and urea, genital mycoplasma grows very slowly, grows faster when subculture again, can not grow in liquid medium and aerobic conditions After growth, the medium is fine-grained and slightly turbid. In the N2 environment containing 5% CO2, the mycoplasma can grow on the solid medium to form a "fried egg"-like colony. The colony size is extremely inconsistent and the diameter is 20 ~200m, which can be inhibited by erythromycin and other antibiotics. It adheres to the surface of glass, plastic and epithelial cells, and invades and enters epithelial cells. It also has the ability to slide and has the ability to adsorb human and animal red blood cells.
Its genome is 600Kbp, which is the smallest of all mycoplasma genomes, and its adhesion structure (MGPa) is 1.4×105 membrane protein.
Ureaplasma urealyticum
Ureaplasma urealyticum, formerly known as T-mycoplasmas, belongs to the genus Ureaplasma of the human mycoplasma. There are 12 serotypes, A and B, which are the smallest free life that can be propagated in cell-free medium. Prokaryotic microbes, mainly spherical in liquid medium, about 50-300 nm in diameter, single or double-arranged, can pass 0.45 m microporous membrane, no cell wall, negative for Gram stain, but not easy to color, Giemsa The staining is purple-blue. The biological characteristic different from other mycoplasmas is that it has urease, which can decompose urea, produce ammonia and CO2, and can change the medium of phenol red from yellow to red. It can grow on artificial medium, but nutrition. High requirements, need to supply cholesterol, yeast and uremic, it has three layers of cell membrane, two layers of protein inside and outside, middle layer lipid, antigenic mainly from cell membrane and urease, lipid part and urease as its specific antigen, can be used as immunogen Inducible specific antibodies (IgM), intracellular ribosomes and double-stranded DNA, are easily lysed by lipid solvents, ethanol, detergents, specific antibodies and complement due to cell-free walls.
(two) pathogenesis
After invading the human genitourinary system, the pathogen adheres to the surface of the mucosal cells and can be inserted into the epithelial cells. The pathogenicity of mycoplasma is low. Except for the production of neurotoxins, it does not produce severe exotoxin, and it damages cells and organs. May be related to its secretion of toxic metabolites.
Pathological changes are similar to those caused by bacterial origin. The most susceptible organs of Ureaplasma urealyticum perinatal infection are placental tissue, chorioamnion, fetus and neonatal lung. The basic pathology of the brain is seen as acute and chronic inflammation. Lesion.
Prevention
Urogenital mycoplasma infection prevention
1. The vaccine has not yet been adopted.
2. Intimate persons who are in close contact or who have other heavier diseases can be prevented by antibiotics such as erythromycin.
3. Strengthen sexual ethics, sexual health education, and check and treat high-risk groups and their sexual partners.
Complication
Urogenital mycoplasma infection complications Complications , endometritis, premature rupture of membranes
Pregnant women can be complicated by endometritis, pregnancy poisoning, premature delivery, premature rupture of membranes and other complications.
Symptom
Urinary genital mycoplasma infection symptoms common symptoms true bacteria urinary urgency urinary frequency urinary tract burning urinary pain vaginal discharge increased itching abdominal pain spontaneous abortion dyspnea
1. Non-gonococcal urethritis (NGU) has urgency, frequent urination, urinary tract burning, dysuria, dysuria and secretions in the urethra, redness and swelling outside the urethra, tenderness along the urethra, redness in the urine, white blood cells; The urethral secretion smear was examined without gonorrhea.
2. Most patients with pelvic inflammatory disease have acute or subacute salpingitis, abdominal pain, aversion to cold and fever; lower abdomen tension, tenderness, tenderness in the attachment area; increased white blood cell count, acute pelvic connective tissue inflammation, pelvic mass The tenderness is obvious.
3. Vaginitis and cervicitis increased vaginal discharge, genital itching; vagina and cervical mucosa congestion.
4. Pregnant women with mycoplasmosis, metritis, infertility, spontaneous abortion, fetal death, etc.
5. Others can also cause chronic prostatitis, epididymitis, male infertility and so on.
6. Perinatal infection (Ureaplasma urealyticum) can cause stillbirth, stillbirth, miscarriage, premature delivery, low birth weight infants, survivors are mainly
1 neonatal pneumonia: may have acute, prolonged and chronic processes, the symptoms are different, most of them are subclinical and light, no clinical symptoms or only mild dyspnea, no snoring or a small amount of fine phlegm in the lungs Sound, X-ray chest has a small piece of shadow or texture thickening, a small number of people can die due to respiratory failure.
2 neonatal meningitis: clinical manifestations of different severity, mild asymptomatic or only mild, moderate fever, slightly poor milk reaction, irritability, cerebrospinal fluid routine normal or mild abnormalities, mycoplasma culture positive, the course of disease Self-limiting, no sequelae, severe cases are more common in premature or very low birth weight infants, clinical manifestations of convulsions or severe inhibition, increased number of conventional cerebrospinal fluid cells, increased proportion of neutral or lymphocytes, severe cases can be combined with intraventricular hemorrhage or ventricles Expanded, hydrocephalus.
3 sepsis: the incidence is not high, the clinical symptoms are not typical, only manifested as non-specific symptoms such as refusal to milk, less crying, poor response.
Examine
Examination of urogenital mycoplasma infection
Specimen collection
Male patients can take urogenital secretions, prostatic fluid, semen, quantitative culture can take early urine, middle urine, women in addition to cervical and vaginal swabs, amniotic fluid, urethral secretions can also be used for testing, if you want to test specific antibodies, Blood specimens should be collected and collected as soon as possible after collection. Generally, the specimens should not be more than 3 hours. Because the mycoplasma has no cell wall, it is particularly sensitive to drying, and the accumulation of metabolites is not conducive to its growth and reproduction.
The laboratory diagnosis of mycoplasma is culture, specific antibody detection, metabolic inhibition test, DNA probe and PCR technology, etc., to the most reliable culture, PCR technology is the most sensitive.
2. Isolation and culture
According to the patient's gender and lesions, different specimens were taken under sterile conditions, and immediately inoculated in liquid medium. When the color of the liquid medium changed, it was transferred to solid medium.
3. Specific antibody detection
Some patients with Mycoplasma genitalium infection can detect antibodies, but the sensitivity is not high, the repeatability is poor, and it can not be used in clinical practice. IgM and IgG antibodies of Ureaplasma urealyticum can be detected by ELISA, which is sensitive and specific. Early diagnosis.
4.DNA probe technology
This method is sensitive and difficult to promote and apply due to the need for isotopes.
5.PCR technology
Because of its high sensitivity and good specificity, it has entered the clinical application stage from the experimental research stage, and has gradually become an important means for rapid clinical diagnosis.
Endoscopy can directly observe inflammatory lesions of the genitourinary system.
Diagnosis
Diagnosis and diagnosis of urogenital mycoplasma infection
diagnosis
1. Epidemiology has a history of contact with patients or carriers within a few weeks before the onset of illness.
2. Different conditions depending on the infection site
(1) urethritis: urgency, frequent urination, dysuria, difficulty urinating; secretions in the urethra, redness and swelling in the urine.
(2) vaginitis and cervicitis: increased vaginal secretions, genital itching, vaginal and cervical mucosal congestion.
(3) pelvic inflammatory disease: most patients with acute or subacute salpingitis, lower abdominal pain with muscle tension, tenderness, aversion to cold fever, pelvic cavity may have a mass.
(4) Others: may have prostatitis, epididymitis, amnion, spontaneous abortion, premature birth, etc.
3. Laboratory examination through mycoplasma culture, specific antibody detection, DNA probe and PCR technology test results can help to clarify the pathogenic diagnosis.
Differential diagnosis
The disease should be distinguished from gonococcal urethritis, fungi, trichomoniasis or other bacterial infections.
