Blood test for chlamydia in men decoding. How are tests for chlamydia diagnosed? Most common causes of false positive tests

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As you know, every disease has its own, inherent only to it, signs. But it has nothing to do with chlamydia.
Chlamydia- this is a disease that does not have clear symptoms that are unique to it, and sometimes it is completely asymptomatic. And even if some are manifested, then most often they are similar to the signs of other STDs.
Therefore, laboratory research methods are decisive for making a diagnosis. Unlike many other diseases, the diagnosis of chlamydia is purely laboratory.

Who should be screened for chlamydia first?

• Men and women who have many sexual partners, especially casual ones.
• Persons whose sexual partners are found to have chlamydia, even in the absence of complaints and symptoms. After all, complications of chlamydia can develop even with its asymptomatic course. The risk of infecting a partner is about 90%.
• Women suffering from infertility for more than 2 years, even if the sexual partner is examined and healthy.
• Women with cervical erosion, cervicitis, inflammation of the ovaries (especially when planning pregnancy). Moreover, the vaginal smear may be normal.
• Women with impaired pregnancy: spontaneous miscarriage, premature birth, polyhydramnios, fever of unknown origin during this pregnancy.

What are they researching?
To detect chlamydia, it is necessary to make a sampling of the material. It can be a scraping containing cells of a diseased organ - the vagina, cervix, prostate secretion, scraping from the urethra, conjunctiva of the eye. Such material can also be blood, urine and semen in men.

What tests are prescribed for chlamydia and how useful can they be?
First, we will dwell on the possible methods of examination, and then we will conclude which of them are most preferable.

2. Immunocytological analysis - Direct immunofluorescence reaction (RIF or PIF).
This method involves the direct detection of chlamydia antigens. For this, the material obtained by scraping is treated with special antibodies that are directly treated with a fluorescent substance. These antibodies bind to specific chlamydia antigens. Then, with fluorescent microscopy, chlamydial inclusions in the cells are determined by a green or yellow-green glow.
The immunocytological method is used in both the acute and chronic phases of the disease.
A significant disadvantage of RIF is a large number of false negative and false positive results. False-negative results are most often associated with violation of the rules for sampling biological material. False-positive results may be due to combined infections of the urogenital tract, when other microbial flora is present along with chlamydia. Among other things, the RIF is very subjective, because. depends on the experience and personal assessment of the laboratory assistant. Therefore, RIF gives a very high percentage of false positive results and cannot be considered reliable. The disadvantage of RIF is also that it cannot be used to evaluate the results of treatment.
With urogenital chlamydia, the accuracy of the method is about 50%.

3. Enzyme immunoassay (ELISA).
ELISA is a method for indirect detection of bacteria, i.e. the pathogen is not detected directly, but specific antibodies (IgG, IgA, IgM) to it are determined. The method is based on the ability of the immune system to produce antibodies ( immunoglobulins, Ig) in response to the introduction of foreign agents.
The advantages of ELISA are that it allows not only to identify the causative agent of the disease, but also to determine at what stage it is (acute or chronic) and evaluate the effectiveness of the treatment. The advantage is also the automation of the method and the speed of its implementation.

How are the results evaluated?
When infected with chlamydia, specific antibodies appear on the 5-20th day of the disease. In this case, the appearance of each class of antibodies occurs at a certain stage of the disease.

• In primary infection, IgM appears first, then IgA, and lastly IgG.
• The very first after the primary infection (after 5 days) appear IgM, which protect the body from the possible spread of infection. They are markers of the acute stage of the disease. By the 10th day, the amount of IgM in the blood reaches a peak. Then their level begins to decrease, and IgA appear. For a short period of time, IgM and IgA antibodies can be detected in parallel. This period indicates the height of the infectious process.
• IgA can be detected 10 days after the onset of the primary symptoms of the disease. They protect the mucous membranes from the penetration of bacteria deep into the tissues. A high level of IgA in mucosal secretions indicates a well-functioning local immunity.
• Then, 15-20 days after the introduction of Chlamydia trachomatis into the body, IgG appears in the blood, and the level of IgA decreases.
• The acute primary process is characterized by a high level (titer) of IgM in combination with a low titer of IgG.
• With re-infection, there is a rapid increase in the titer of IgG and IgA and the almost complete absence of IgM.
• In the chronic course, specific IgG and A are detected, the concentrations of which do not change for a long time.
• When cured after 1.5-2 months, IgA and IgM are not detected in the blood, and IgG can persist for several years, but their level decreases by 4-6 times.
• Long-term detectable IgG indicates past chlamydial infection.
• With an exacerbation of chlamydia, the amount of IgA and IgG increases several times.
• The effectiveness of the treatment is determined by the presence of IgA. If IgA is detected in the blood 2 months after the course of treatment, this means that the infection has remained.

It should be noted that specific antibodies produced to chlamydia do not provide stable immunity against them.
The accuracy of this test for chlamydia is about 70%. This is due to the fact that antibodies to chlamydia can also be present in healthy people due to a previous illness, as well as be determined in respiratory and other types of chlamydial infections.

4. Polymerase chain reaction (PCR).
Using PCR, a specific site or DNA fragment of chlamydia is detected in the material under study, therefore, in comparison with other methods, it is impossible to confuse chlamydia with some other infection. It is effective in both acute and chronic phases of the disease. At the same time, very little material is needed for analysis, but the results are ready in 1-2 days.
For PCR research, the material can be scraping from the urethra or cervical canal, prostate secretion, urine sediment, scraping from the conjunctiva of the eyes, blood.
When diagnosing a primary infection, it is more informative to identify this infection in the places of initial localization, i.e. the material should be scrapings from the genital tract. False-positive PCR results may be in case of violation of the process of sampling, transporting the material and conducting the analysis itself.

Important! To assess the effectiveness of PCR treatment, the study cannot be carried out earlier than a month after the course of antibiotic therapy, because. you can get false positive results. This is due to the fact that when a DNA fragment of chlamydia is detected, it is impossible to assess how viable the microbial cell itself is. In this case, the viability of chlamydia, as well as the possibility of recurrence of the disease associated with it, is assessed using a microbiological method. If chlamydia is not viable, then despite the presence of a DNA fragment, microbial cells will not grow in cell culture.
To date, the accuracy of this method is the highest - up to 100%.
This method is recommended as the preferred method in the diagnosis of chlamydial infection.

5. Microbiological examination (cultural method) with the determination of sensitivity to antibiotics.
The essence of this method is that the studied material is sown on a special medium and grown. Then, the pathogen is identified by the nature of growth and other signs. The cultural method is the most sensitive, it allows not only to identify viable chlamydia, but also to select an antibiotic to which this microorganism is sensitive.
Scraping from the urethra, cervix, prostate secretion, scraping from the conjunctiva of the eye can serve as material for research.
One month before the study, antibiotics should not be used.
Microbiological examination is preferable to carry out in the following cases:

• To evaluate the effectiveness of the antibiotic treatment.
• To detect sensitivity to antibacterial drugs.
• To detect chlamydia in people with immunodeficiencies (HIV infected, cancer patients after radiation and chemotherapy, people receiving immunosuppressants, etc.).

The disadvantages of the cultural method for diagnosing chlamydia are the complexity, high cost and duration of the study. It also requires special laboratory equipment and very high qualification of personnel. In addition, this method, like no other, requires impeccable compliance with the rules for the collection of material, transportation and storage.
The actual term for obtaining results by this method is at least seven days.
The detection rate of chlamydia during sowing is up to 90%.

6. Express diagnostics.
All methods of rapid diagnosis of chlamydia are based on enzyme-specific reaction and immunochromatography. For this, special kits for express diagnostics are used, which allow you to visually evaluate the results in 10-15 minutes. This is a very fast and convenient method, but its accuracy is only 20-25%.

Conclusions.

• There is no single method that would detect chlamydia in 100% of cases. Therefore, in most cases, laboratory diagnostics should include a combination of at least two methods.
• The most sensitive tests for chlamydia are PCR (DNA - diagnostics) and microbiological analysis. They are the "legal standard" for diagnosing chlamydia.
• In the case of primary infection, one PCR test is usually sufficient before the use of antibiotics.
• In chronic processes - PCR or microbiological test, or RIF + ELISA.
• With the probability of the transition of the pathogen into the L-form - ELISA.
• Microbiological examination is ideally used to evaluate the effectiveness of treatment. If it is impossible to conduct it - PCR + ELISA.
• To determine the stage of the disease - ELISA.
• In patients with immunodeficiencies, ELISA is not informative; ideally, a microbiological method should be used.
• You should not rely too much on the results of determining the sensitivity of chlamydia to antibiotics. After all, as you know, microorganisms behave differently in a test tube (in vitro) and in a living organism (in vivo).

Content

A serious infection, often sexually transmitted, is dangerous with severe consequences. Laboratory diagnostic methods - blood tests for chlamydia - help to identify the disease, start its treatment. What are the features of surveys, how informative are all their varieties, how the results are deciphered - questions that are interesting to get answers to.

Chlamydia trachomatis - what is it

• during unprotected intercourse;
• household way;
• during pregnancy from an infected mother to a child;

• for men, the disease is dangerous by the development of prostatitis, impotence, chlamydial pneumonia;
• in women, chlamydia provoke miscarriages, adhesions in the pelvis, premature birth, tumors of the uterus.

Diagnosis of chlamydia

The disease may be asymptomatic for a long period after infection. Often chlamydia is detected in the diagnosis of other sexually transmitted infections. Due to the characteristics of the biological cycle of the pathogen, analyzes are carried out in several ways. Laboratory diagnosis of chlamydia includes research methods:

• primary microscopic analysis of the smear;
• cultural method - sowing biomaterial in a special environment - gives an accurate result;
• RIF of chlamydia - determination of the immunofluorescence reaction - pathogens glow under a microscope, it is reliable.

Analysis for chlamydia

Blood tests are the most accurate diagnosis for detecting chlamydial infection. They are produced according to several methods that have their own characteristics. The main types of examination:

• Immunoassay - ELISA. By the amount of Igg, Igm, Iga antibodies, it is determined which phase is currently observed in the disease - acute, chronic or remission.
• Polymer chain reaction - PCR. Detects pathogen DNA, is a very reliable diagnostic method.

• having unprotected sex with a new sexual partner;
• women who have frequent ailments due to pelvic diseases;
• both partners when planning pregnancy, so as not to infect the expected baby;
• women who have problems bearing a child;
• patients with unexplained causes of infertility.

Blood for chlamydia is taken from a vein. To obtain objective results, doctors recommend that you comply with the requirements:

• do tests not earlier than a month after antibiotic treatment;
• do not have sexual intercourse in the coming days before the examination;
• do not smoke half an hour before blood sampling;
• come to the study on an empty stomach;
• do not drink alcohol during the day;
• do not drink water before testing;
• exclude the implementation of physiotherapy.

PCR for chlamydia

With this research method, chlamydia in the blood is determined by the amount of DNA of microorganisms that are in the selected sample. Polymer chain reaction analysis - PCR - is characterized by very high accuracy and sensitivity. The result is fast and reliable. It is considered positive with a large number of chlamydia in the sample for research - the cause of infection is confirmed. The advantage of the method is that it detects infections:

• in a hidden form;
• oligosymptomatic;
• at the acute stage.

Chlamydia poses a great danger to a woman who is expecting the birth of a baby. There is a high probability of intrauterine infection. Timely diagnosis will help to start treatment at an early stage, to avoid serious problems. Chlamydia PCR analysis is prescribed by gynecologists to exclude infection when a pregnant woman has symptoms:

• elevated temperature;
• soreness in the lower abdomen;
• bad feeling.

The PCR blood test is universal. With its help, not only the causative agent of chlamydia is determined, but also other infections - herpes, tuberculosis, hepatitis. When decrypting, two options are possible:

• negative - indicates the absence of infection of the body;
• positive - indicates that infection has occurred, and by what type of bacteria.

ELISA for chlamydia

From the first days of infection, the body begins to produce antibodies to chlamydia in the blood. Three types of immunoglobulins stand up to protect against the disease, which are called Igg, Igm, Iga. Enzyme-linked immunosorbent assay - ELISA for chlamydia not only accurately determines their presence, but states the stage in which the disease is located. This is due to the appearance of each of the antibodies at a particular stage of infection.

When examining blood by ELISA, immunoglobulins are detected at the following times:

• after infection, Igm immediately appears, if the other two are absent, acute inflammation is diagnosed, it is important when examining newborns;
• a month after infection, Iga antibodies are formed, which indicate the progression of the disease;
• the appearance of Igg signals the transition of chlamydial infection into its chronic form.

Deciphering the analysis for chlamydia

Interpretation of the results of the survey has subtleties, so it should be carried out by qualified specialists. A blood test for chlamydia ELISA stands for each type of immunoglobulin, indicates the period of development of the infection. When determining Igm, the results are:

• Positive: less than two weeks have passed since infection; if other antibodies are not detected, in the presence of Igg, an exacerbation of chronic inflammation.
• Negative: no chlamydia - in the absence of all immunoglobulins; when Igg is detected - infection occurred at least two months ago.

In blood tests for the presence of Iga antibodies, the result is interpreted as follows:

• Positive: acute stage of chronic infection or infection more than two weeks old; infection of the child during pregnancy.
• Negative: no chlamydial inflammation; from the time of illness less than 14 days; there is little chance of fetal infection.

When decoding the test for Igg, the following results are produced:

• At the norm - absent, the value of the coefficient of positivity is in the range of 0–0.99;
• Positive: Chlamydia infection or flare-up occurred more than three weeks ago.
• Negative - in case of simultaneous absence of Iga Igm immunoglobulins: no chlamydia in the blood; full recovery.

Where to get tested for chlamydia

Those who have felt signs of the disease, had unprotected sex with a casual partner, can be purchased at the pharmacy for an express test. With its help, the presence of chlamydia infection is quickly determined. For analysis, you need urine or a smear in women. The instructions describe how to collect them. The result is decoded like this:

• positive - requires immediate contact with a venereologist for the appointment of drug treatment;
• a negative test indicates that the disease is absent at the time of the test.

You can get tested for chlamydia by referral from a venereologist or gynecologist. It is not excluded that the patient independently applies to medical institutions if infection is suspected. A blood test for chlamydia is carried out by such organizations:

• women's consultations;
• family planning clinics;
• skin and venereal dispensaries;
• specialized laboratories for research.

How much does a chlamydia test cost?

Testing for chlamydia can be done at clinics or specialized centers that provide such services. The cost depends on the status of the institution, the available equipment. The classification of specialists involved in deciphering the results plays a role. The price of analysis for chlamydia in medical organizations in Moscow is summarized in the table:

Video: how to take a blood test for chlamydia

Attention! The information provided in the article is for informational purposes only. The materials of the article do not call for self-treatment. Only a qualified doctor can make a diagnosis and give recommendations for treatment, based on the individual characteristics of a particular patient.

In women, chlamydia affects the cellular material of the ovaries, fallopian tubes, uterus, migrating into the peritoneum.

In men, the disease affects the ureters, urethra, seminal vesicles, prostate gland.

When typical symptoms of chlamydia appear - painful sensations during urination, pulling pains, discharge, a blood test should be taken.

Where to turn, to which doctor? The direction is given by a narrow specialist - venereologist, urologist, gynecologist. Deciphering the tests for chlamydia is carried out by the attending doctor after studying the history of the anamnesis.

Deciphering a blood test for chlamydia

The results of tests for chlamydia make it possible to exclude / confirm the presence of the pathogen Chlamydia trachomatis.

Diagnosis is performed by two main methods - ELISA and PCR.

Deciphering the analysis of ELISA for chlamydia

ELISA determines the protein compounds in the blood to chlamydia, detects which titers are growing, which are not. Proteins M, G, A are of value for diagnostics.

10-14 days after infection, immunoglobulins of classes M and A begin to appear. The titer of G antibodies increases gradually, being determined in the analysis after 14-21 days.

When positive after treatment with IgG, this is a variant of the norm.

Antibodies can be detected for another 3-4 months after completion of the course of therapy. The detection of only one titer is uninformative.

Therefore, in order to correctly interpret the results of tests for chlamydia, a test for 2-3 immunoglobulins is performed simultaneously (G + M, G + A). For greater information content of the analysis, two-fold detection of G.

The active process manifests itself by an increase in the concentration of immunoglobulins by 5-6 times. This allows the diagnosis of acute infection without testing for A or M.

Test results for chlamydia trachomatis

Transcription of tests for chlamydia (titles)

ELISA Benefits:

• detection of the pathogen at the initial stage
• determination of a specific type of immunoglobulins, which allows you to choose an adequate drug regimen, make a forecast for the course of the infection, the timing of recovery
• control over the course of therapy
• sensitivity even at a low concentration of a biological substance
• specificity, which guarantees the reliability of the result in 60-85% of cases
• efficiency of diagnostics

Disadvantages:

• you need to know exactly what pathology to look for. Performing an analysis requires the doctor to have an assumption about the nature and genesis of the disease.
• the test detects only the presence of certain immunoglobulins, and not the source of infection and a specific pathogen
• the method requires highly qualified medical personnel for the correct interpretation of the data obtained

How is a blood test for chlamydia done?

Before passing the analysis, it is worth avoiding stressful situations, intense physical exertion, smoking, taking medications, and alcohol-containing drinks.

Women should talk to their doctor if she is taking oral contraceptives. Since changes in hormonal levels can distort the test data.

It is not recommended to douche, donate blood while taking antibiotics, during menstruation. The results of a blood test for chlamydia are issued on a form with the wording doubtful, positive, negative.

Immunoenzymatic analysis can give erroneous readings.

False positive tests are obtained due to a recent infection, the presence of autoimmune pathologies.

False-negative - due to the slow production of immunoglobulins, weakened immunity.

Deciphering the PCR analysis for chlamydia

polymerase chain reaction- informative and reliable diagnostic method. Allows you to make a conclusion with 100% certainty about the absence / presence of chlamydial infection in the body.

The essence of the method lies in the interpretation of a DNA segment, the study of the element of which helps to identify the pathogen. Materials for testing - smear, urine, blood, saliva.

PCR is prescribed for dynamic monitoring of treatment, with complicated pregnancy, infertility of unknown origin, HIV, tuberculosis, hepatitis.

How is a PCR test for chlamydia performed?

Various biological materials are suitable for a smear - sexual secretions, urine, blood. Women most often take a vaginal smear with a medical probe, using a mirror, place it in a clean flask, and send it for preparation.

Men donate a portion of urine, ejaculate or urogenital scraping.

For pregnant women, a PCR test is mandatory - it helps prevent infection of the fetus.

Manipulation is fast and painless. The amniotic sac is not damaged during the sampling process, the cervix does not expand.

Advantages:

• identification of the causative agent of the disease, and not marker proteins or antibodies
• high sensitivity, specificity
• efficiency of data acquisition
• versatility of bacteria detection technology
• the possibility of detecting a latent/asymptomatic infection

Deciphering the analysis for chlamydia in men and women

PCR is a qualitative method, the result is given to the patient in two versions:

• discovered. Infection found in the material
• not detected. There were no signs of Chlamydia trachomatis

Deciphering the analysis for chlamydia PCR with concentration

The study of PCR can be quantitative - this helps to choose an adequate line of etiotropic therapy.

A high bacterial load implies the appointment of a high dose of drugs and an increase in the duration of treatment.

When the test is scheduled:

• inflammatory pathologies of the reproductive system: cervicitis, prostatitis, urethritis
• pain in the abdomen, lumbar region, burning sensation in the genitals, purulent discharge, temperature fluctuations, frequent urination
• somatic chronic inflammation: pneumonia, conjunctivitis, arthritis
• problems with conception
• ectopic pregnancy
• questionable sexual contact
• pregnancy planning
• preparation for surgery

How to Prepare for a Chlamydia Test

A blood test is taken on an empty stomach to prevent getting a distorted result.

You can not eat fried and fatty foods for 24-48 hours, you should limit the intake of alcoholic beverages, do not smoke.

Urine for the test must be collected in the morning in a container, after having carried out hygiene of the external genitalia. Taking a smear means refraining from sexual intercourse 48 hours before manipulation. It is recommended not to visit the toilet room 1.5-2.5 hours before the test.

Sometimes an analysis of the synovial fluid is prescribed: for the sample, a puncture of the joint is performed - the knee or elbow.

To obtain the most reliable result, it is recommended to give up alcohol 24 hours before the procedure, avoid ultrasound, MRI, and medication.

Tests for chlamydia after the end of the course of treatment

Treatment of chlamydia should be adequate and timely. The drugs of choice are josamycin and doxycycline.

In 40% of cases, specific therapy does not lead to the elimination of chlamydia. This is due to changes in the immune system affected by Chlamydia trachomatis and an increase in the number of antibiotic-tolerant microorganisms. Therefore, it is very important to prescribe a combined regimen for patients: antibacterial drugs + immunomodulatory agents.

After completion of treatment, a re-diagnosis is performed, which allows you to verify the effectiveness of therapy. If the result of the analysis shows the presence of infection, a second course is required using antibiotics from a different clinical group.

If laboratory tests show the absence of chlamydia in the biological material, the patient is considered completely cured.

Chlamydial infection often occurs in a latent form. It is observed as an oligosymptomatic inflammatory process of the urethra. This leads to health problems: allergies develop, conjunctivitis develops, memory problems arise.

To prevent such a situation, it is necessary to undergo an examination for the presence of Chlamydia trachomatis and start treatment in a timely manner.

For the delivery and interpretation of tests for chlamydia, please contact the author of this article - a venereologist in Moscow with many years of experience.

Chlamydia trachomatis is one of the most common causative agents of sexually transmitted infections.

The results of tests for chlamydia can confirm or exclude the presence of a pathogen in the human body. Two main methods are used to diagnose chlamydial infection.

The first one is PCR. It involves the detection of pathogen DNA in clinical material.

The second method is ELISA. With its help, antibodies to chlamydia are detected in the patient's blood. They are produced by the immune system.

The presence of these antibodies indicates that the patient is ill or has recently had an infection. Deciphering tests for chlamydia should be carried out by a venereologist. Often, to obtain a reliable result, the results of tests for chlamydia are required after performing both tests - PCR and ELISA.

PCR is considered more reliable. It is sensitive and specific. Whereas blood tests are often used as a screening diagnostic method.

Chlamydia blood test results

For a person who takes a blood test for chlamydia, decoding presents certain difficulties. There are different types of immunoglobulins in the blood. There are 5 classes in total. Three classes are of diagnostic value in chlamydia.

In the blood, the titer of immunoglobulins M, A and G is determined in the analysis for chlamydia by ELISA. Decoding depends not only on the concentration of various antibodies, but also on the dynamics of its increase or decrease.

Everything immunoglobulins are proteins produced by the immune system.

They help her fight the causative agent of the infection. Some antibodies are formed shortly after infection. At the same time, the synthesis of other immunoglobulins takes much longer.

The timing of their disappearance from the blood also differs. Those immunoglobulins that are produced earlier disappear in a shorter time. At the same time, antibodies, the titer of which increases slowly, can circulate in the blood for a long time.

Immunoglobulins of classes A and M appear quickly enough. They are determined in the blood within 1-2 weeks after infection. But the titer of immunoglobulin G increases rather slowly. These antibodies do not disappear until the person is cured of chlamydia. And even after treatment, they can be determined for several more months. As a rule, a person is tested for several types of antibodies at once.

Because the isolated determination of the titer of one class of immunoglobulins gives the doctor a minimum of information. The analysis is done immediately for 2 or 3 types of antibodies. This is necessarily immunoglobulin G, as well as M or A (or both classes of immunoglobulins).

The presence of IgA or IgM in the blood indicates that the infection is acute. Most likely, the infection occurred quite recently. Because after one and a half to two months in the chronic course of chlamydia, these immunoglobulins may no longer be detected in the blood. The absence of IgG clearly indicates early infection. Because these immunoglobulins are formed later. If IgG is present in a blood test for chlamydia along with other classes of antibodies, this indicates that the person has chlamydia. He became infected more than 3 weeks ago. Sometimes IgG antibodies are detected in the blood in the absence of immunoglobulins A or M. This result is ambiguous. He can talk about both the current chronic infection and the chlamydia transferred in the past.

Decoding of analyzes: determination of IgG titer to chlamydia in dynamics

To increase the information content of the serological method for diagnosing chlamydia, a double determination of IgG is used.

So the doctor sees whether the titer (concentration) of antibodies increases or decreases. Typically, the study is carried out with a gap of 2 weeks. An increase in IgG titer by 4 or more times indicates active chlamydia. In this case, an acute infection can be diagnosed even without a blood test for IgM or IgA.

Decoding tests for chlamydia: false positive or false negative results

The results of serological diagnosis are not always reliable. They can be false positives or false negatives.

False positive analysis is the detection of chlamydia in a person who does not actually have it.

A false negative test is the failure to detect chlamydia in a patient who is infected with chlamydia.

The most common causes of false positive tests are:

• previous infection;
• the presence of other infections;
• autoimmune diseases.

False negative results are possible with:

• weak immune response and slow production of immunoglobulins;
• a recent infection that occurred less than 3 weeks ago.

False positive analysis is less of a problem because the ELISA result must be confirmed by PCR. Therefore, no one will treat a healthy person. But a false negative analysis leads to the fact that a sick person does not receive therapy. He may develop complications. In addition, the infection will spread among his sexual partners. Therefore, if there are signs of chlamydia, it is better to immediately take two tests: ELISA and PCR in order to get reliable results.

PCR analysis for chlamydia - transcript

Since deciphering the results of tests for chlamydia after an ELISA can not always give an unambiguous answer whether a person is sick, a confirmatory study is required.

The determination of antibodies in the blood is screening (mass) diagnostic method. It is often given to women who are pregnant or about to become pregnant. This analysis is simple and convenient - it is performed simultaneously with studies for other infections. But if an elevated titer of immunoglobulins is detected, the diagnosis is not immediately made. It must be confirmed by PCR.

For this, scraping of cells from the urogenital tract is most often used as a clinical material. In men, chlamydia most often causes urethritis. In women, it often causes cervicitis - inflammation of the cervix. Deciphering the analysis for chlamydia in men and women is not at all complicated. The results of the study usually get either a positive or a negative result. That is, chlamydia is either detected or not detected.

This is a pathogenic microorganism. Therefore, for the diagnosis, its concentration in the structures of the genitourinary system does not matter. The indication for therapy is the very fact of the detection of chlamydia.

Deciphering the analysis for chlamydia PCR with concentration

A PCR test for chlamydia can be not only qualitative, but also quantitative. This diagnostic method is more expensive, but it is more informative.

Determining the concentration of chlamydia helps in choosing the optimal etiotropic treatment regimen. The higher the bacterial load, the higher the doses of the drugs, and the longer the treatment should continue.

Deciphering the analysis for chlamydia in women and men is carried out only by a doctor. He also prescribes treatment aimed at eradicating the pathogen.

If you need to take tests for chlamydia or decipher the results of previous studies, please contact our clinic. We have highly qualified venereologists.

If you suspect chlamydia, contact a competent venereologist.

Analysis for chlamydia as part of a preventive examination plays an important role. This is because chlamydia is often asymptomatic. The material for research can be tissue samples, blood, urine and other biological fluids.

Chlamydial infections are a group of infectious diseases caused by chlamydia. Bacteria of this genus affect the organs of the genitourinary, respiratory, cardiovascular, visual, and musculoskeletal systems.

A blood test for chlamydia is performed using venous blood, which is given in the morning on an empty stomach.

Indications for testing for chlamydia

An examination for chlamydia is indicated in the following cases:

• preventive examination;
• signs of sexual infection;
• pregnancy planning;
• complicated pregnancy in history;
• obstetric registration;
• inflammatory diseases of the urinary organs;
• no pregnancy within 2-3 years of regular sexual activity;
• monitoring the effectiveness of chlamydia therapy;
• individuals whose sexual partners are found to have chlamydia.

Types of tests for chlamydia

Diagnosis of chlamydia is carried out in several ways.

Cultural analysis

The study of biomaterial by means of sowing, the isolation of the culture of the pathogen and the determination of its sensitivity to antibiotics. Chlamydia isolates infect susceptible cells during the isolate assay. Then a growth medium containing an antibiotic is added to them. Infected cell cultures are incubated at +36°C for five days. Depending on the suppression of infection determine the sensitivity to the antibiotic. Seeding for chlamydia is used in evaluating the effectiveness of antibacterial treatment; the disadvantages of the method include the laboriousness of the process and the duration of preparation.

Cytological smear examination

The method is informative only in acute forms of the disease. Epithelial scrapings serve as clinical material for the study. During the study, the biomaterial is exposed to fixing agents and staining. Under the influence of reagents, preparations are detected under a light microscope.

The results of the study are individual for different types of infection, only a doctor should deal with their decoding and determining the nature of the treatment.

Immunofluorescence reaction (RIF)

Detection of chlamydia antigens using a fluorescent microscope. The method is based on the property of antibodies to differ from each other by the brightness of the glow, while inclusions of chlamydia stand out against the background of the cytoplasm of cells. This method is not sensitive enough for asymptomatic disease.

Enzyme immunoassay (ELISA)

A method based on the detection of specific antibodies to chlamydia in test samples. Allows you to determine the phase of the disease, to evaluate the effectiveness of antibacterial treatment. Thus, the production of IgM antibodies to Chlamydia trachomatis is a marker of the acute stage of the process. With the progression of the disease and its transition to a chronic form, IgA antibodies appear, then IgG.

The decoding of enzyme immunoassay is presented in the table.

Polymerase chain reaction (PCR)

A method for detecting pathogen DNA fragments, which allows you to confirm the presence of a foreign microorganism in the body with an accuracy of 90-95% and determine what kind of microorganism it is. Samples of tissue, blood, urine, and other biological fluids can be taken for analysis. In women, epithelial scrapings are taken from the vagina, urethra, and cervix. In men, a smear from the urethra, prostate secretion, ejaculate are used. If the eyes are affected, scrapings from the conjunctiva are examined. To exclude rheumatic damage to the osteoarticular system, the joint fluid is examined.

Use special devices - amplifiers for DNA multiplication. When the amount of DNA is sufficient, it is determined whether the sample contains DNA fragments characteristic of the infectious agent. The assessment is carried out by electrophoresis or using labeled DNA fragments. Normally, the genetic material of chlamydia is not detected.

Chlamydia occupy an intermediate position between viruses and bacteria.

The PCR result can be positive or negative. Quantification in dynamics allows you to determine the activity of the pathogen and the effectiveness of the therapy.

Express Diagnostics

For express diagnostics, immunochromatographic tests are used, the action of which is based on the use of fluorescent markers, while the presence of chlamydia DNA in the sample is determined already in the reaction tube.

To identify chlamydia allows an integrated approach. It is important to consider how much analysis is done. As a rule, after receiving the results of PCR (usually ready 4 days after delivery), additional studies are prescribed - culture and enzyme immunoassay. The results of the study are individual for different types of infection, only a doctor should deal with their decoding and determining the nature of the treatment.

Preparing for a chlamydia test

How do they take material for research and how to hand it over correctly?

A blood test for chlamydia is performed using venous blood, which is given in the morning on an empty stomach.

Preparation for the study includes abstinence from alcohol, fatty and salty foods, smoking during the day. Before taking a biological sample from the urethra, it is recommended not to urinate for several hours.

Antibiotics and uroseptic preparations must be discontinued 30 days before culture. In immunocytological studies, antibacterial drugs are canceled for 14 days.

On the eve of PCR, women are advised to refrain from douching, hygiene procedures with antibacterial soap, and the use of vaginal suppositories. Before collecting material, men must refrain from using medical products to increase potency.

Material for research on chlamydia can serve as tissue samples, blood, urine and other body fluids.

Chlamydia and chlamydia

A person is infected with three types of chlamydia - C. trachomatis, C. Psittaci and C.pneumoniae. The localization of the pathological process depends on the type of bacteria. The urogenital form of chlamydia is caused by Chlamydia trachomatis.

According to the characteristics of the genetic material, there is a similarity with mycoplasma, ureaplasma and Haemophilus influenzae.

Ways of infection:

• sexual- with unprotected sexual contact;
• vertical (from mother to newborn baby)- infection of the fetus through the placenta during pregnancy or during childbirth;
• contact household- through common household items, kisses.

The significant prevalence of chlamydial infection is explained by the asymptomatic nature of the course of the disease. The appearance of the first clinical signs and the development of symptoms (glassy discharge from the urethra, itching, pain and pain during urination, temperature changes, signs of intoxication) depends on the state of immunity. After some time, the symptoms of chlamydia usually disappear, the disease passes into a chronic stage with periods of exacerbation. This form of infection is called persistent.