Urogenital chlamydia is one of the most frequent sexually transmitted infections. The number of cases of chlamydia is steadily increasing; 90 million cases of the disease are registered annually in the world. The prevalence of chlamydia is due to the wear of clinical symptoms, the complexity of diagnosis, the emergence of strains resistant to antibiotics, as well as social factors: an increase in the frequency of extramarital sex, prostitution, etc. newborns.
Etiology and pathogenesis. Chlamydia are Gram-negative bacteria of spherical shape, of small size, belonging to the Chlamidiaceae family of the Chlamidia genus. S. trachomatis (the causative agent of urogenital chlamydiosis, trachoma, lymphogranuloma venereal), C. psittaci (causes atypical pneumonia, arthritis, pyelonephritis), S. pneumoniae (the causative agent of ARD, pneumonia) are most significant for humans. The causative agent has all the main microbiological signs of bacteria, reproduces by simple binary division, but for reproduction it needs the cells of the host organism (intracellular parasitism), which makes it similar to viruses. The unique development cycle of chlamydia includes two forms of existence: elementary bodies (an infectious form adapted to extracellular existence) and reticular bodies (a vegetative form that provides intracellular reproduction). The elementary bodies are phagocytosed by the cell of the host organism, but they are not digested (incomplete phagocytosis), but turn into reticular bodies and actively proliferate. The development cycle of chlamydia is 48-72 hours and ends with the rupture of the host cell with the release of elementary bodies into the extracellular space (Fig. 12.21).
Chlamydia is unstable in the environment, easily die when exposed to antiseptics, ultraviolet rays, boiling, drying.
Infection occurs mainly through sexual intercourse with an infected partner, trans paralysis amber and intranatally, rarely through the household through toilet articles, underwear, bedding. The causative agent of the disease exhibits a high tropism for the cells of the cylindrical epithelium (endocervix, endosalpinx, urethra). In addition, chlamydia, being absorbed by monocytes, are spread with the blood flow and are deposited in the tissues (joints, heart, lungs, etc.), causing a multifocal lesion. The main pathogenetic link of chlamydia is the development of the scar-adhesive process in the affected tissues as a result of the inflammatory reaction.
Chlamydial infection causes marked changes in both cellular and humoral immunity. It should take into account the ability of chlamydia under the influence of inadequate therapy to transform into L-forms and (or) to change its antigenic structure, which complicates the diagnosis and treatment of the disease.
Classification. Fresh (disease duration up to 2 months) and chronic (disease duration more than 2 months) chlamydia are distinguished; there have been cases of carriage of chlamydial infection. In addition, the disease is subdivided into chlamydia of the lower parts of the urogenital system, its upper parts and organs of the small pelvis, and chlamydia of other localization.
Clinical symptoms. The incubation period for chlamydia varies from 5 to 30 days, averaging 2-3 weeks. Urogenital chlamydia is characterized by polymorphism of clinical manifestations, the absence of specific signs, asymptomatic or oligosymptomatic long-term course, and a tendency to relapse. Acute forms of the disease are noted with a mixed infection.
Most often chlamydial infection affects the mucous membrane of the cervical canal. Chlamydial cervicitis often remains asymptomatic. Sometimes patients notice the appearance of serous-purulent discharge from the genital tract, and when joining urethritis – itching in the urethra, painful and frequent urination, purulent discharge from the urethra in the morning (a symptom of the “morning drop”).
An ascending urogenital chlamydial infection determines the development of salpingoophoritis, pelvioperitonitis, and peritonitis, which have no specific signs, except for a protracted “erased” course during chronic inflammation. Consequences of the pelvic dose of the pelvic organs are the adhesions in the uterus, infertility, and ectopic pregnancy.
Extragenital chlamydia should include Reiter’s disease, including the triad: arthritis, conjunctivitis, urethritis.
Chlamydia of the newborn is manifested by vulvovaginitis, urethritis, conjunctivitis, pneumonia.
Due to scarce and (or) non-specific symptoms, it is impossible to recognize the disease on the basis of the clinical picture. The diagnosis of chlamydia is made only according to the results of laboratory research methods. Laboratory diagnosis of chlamydia is to identify the pathogen itself or its antigens. The material for the study are the braces from the cervical canal, the urethra, from the conjunctiva. Microscopy of smears stained according to Romanovsky-Giemsa makes it possible to identify the pathogen in 25-30% of cases. At the same time, the elementary bodies are painted in red, reticular – in blue and blue. Immunofluorescence and enzyme immunoassay using labeled monoclonal antibodies, as well as the molecular-biological method (PCR) are more sensitive. The gold standard for detecting intracellular parasites remains the culture method (isolation from cell culture).
In order to clarify the diagnosis and determine the phase of the disease, detection of chlamydial antibodies of classes A, M, G in serum is used. In the acute phase of chlamydial infection, the IgM titer increases, and upon transition to the chronic phase, IgA titers increase, and then IgG. The decrease in titers of chlamydial antibodies of classes A, G in the course of treatment is an indicator of its effectiveness.