Laboratory diagnosis of syphilis. Modern laboratory methods and syphilis diagnostics algorithms Serological study Syphilis

13.01.2021

The diagnosis of syphilis to this day is considered a rather complicated procedure that does not always guarantee the rapid and correct results. How to check for syphilis and correctly determine the results of all studies conducted?

What is laboratory confirmation of the specified diagnosis, how is it produced? How to diagnose secondary syphilis or latent stage of the disease? Consider these questions in this article.

Diagnostic methods

Collect Anamneza

First of all, if there are suspicion of syphilis, it is necessary to immediately go for consultation to the venereologist. Already at the stage of counseling and inspection, the doctor can put a preliminary analysis.

To diagnose the venereologist need to collect anamnesis, i.e. All the necessary information: the peculiarities of the patient's sexual life, the presence of contacts with possible syphilites, complaints, were previously venereal diseases, etc.

Having received this information, the venereologist focuses on solving the issue, which disease is characteristic of symptoms identified during the collection of history. Next, with the aim of checking for the disease, a clinical examination of the patient is carried out.

Inspection of the patient

The doctor pays the most attention to the inspection and study of the skin and mucous membranes of the genitals, the rear pass, as well as the oral mucosa. The lymph nodes are thoroughly feeling, the foci of their necrosis is detected.

At this stage of the survey, it is possible to recognize the disease with high accuracy, i.e. Replace the primary diagnosis. But to make sure this is 100%, a number of laboratory studies with positive data are needed.

This type of diagnosis is divided into two separate studies. In the first case, you can identify the causative agent of this complex disease, in the second - determine the degree of change in the patient's immunity.

Microscopy

The detection of pale treponam is carried out with the help of a well-known medical technology called the dark-axis microscopy of bacteria. Science is known that Pale Treplema is poorly painted with traditional dyes.

Therefore, on a dark field of a special microscope, it immediately becomes visible as a small spiral. At the same time, the material taken from the ulcers, similar to a syphilitic, which is the result of the primary infection is investigated.

Fluorescence reaction

In this case, the biological material is treated with a special serum, as a result of the action of which the pale treponema begins to glow, it looks very beautiful and elegant.

Polymerase reaction

With this reaction, the doctor will detect the DNA of the pale treponam, i.e. Through PCR, it is possible to finally prove the presence in the body of the patient of this infectious agent.

How to diagnose this disease in immunological indicators? Their study in medicine is referred to as serology. Serodiagnosis has many modern methods, they are widely applied in practice.

All these methods are based on the study of the patient's blood. One group of methods is aimed at allocating antibodies against pale treponam, the second group studies changes in immunity due to the activities of this malicious bacterium.

1) Microscopic precipitation reaction.

During this study, antibodies are detected in the blood of the patient, which were developed by its immune system against the cells of the body damaged as a result of the activity of pale treponama.

This type of testing has high accuracy, but can reveal not only syphilis, but also other diseases (for example, gonorrhea, its pathogens are gonococci). Therefore, with the help of the test, only a suspicion of infection appears.

Preventation is often used not to diagnose, but also study the effectiveness of therapy. If the patient was safely cured, the above reaction becomes negative.

This type of laboratory study differs significantly from other variants of serological studies, which, after cure, can give a positive reaction for a long time, fix the presence of a disease in the human body.

2) Vasserman reaction.

As a result of such testing, "pluses" are put. The more "pros", the more reliable the presence of pale treponam in the human body. The maximum positive result is four "plus" or "++++".

What is trepaline serology?

1) immunological fluorescence reaction.

In the course of this testing, antibodies are detected, which produces human immunity infected with tronamed. In the course of the study, human blood serum interacts with a drug that has an antibody in its composition.

After mixing both components: serum and antibodies marked with a special luminous substance, they bind to each other, after which they are investigated by means of a special microscope.

2) Immuno enzyme analysis.

With this analysis, most infectious diseases are effectively revealed. In the course of it there is an antigen reaction with antibodies of various class. It is easy to determine their quantity.

According to the type of antibodies and their number it is possible to draw conclusions about the diagnosis, the duration of the flow of the detected disease, the development of the pathological process, the activity of the treponam, the power of the patient's immune system.

Thanks to the abundance of indicators of the origin, development and course of the disease, this analysis simply will not be replaced when diagnosing a plurality of infectious diseases. And also as control of their development and cure.

3) hemagglutination reaction.

As a result of this test, red blood cells are glued. Its essence is that after preliminary preparation on the surface of the erythrocytes, the proteins of the treponam are recorded.

These materials are mixed with serum in which there are antibodies to this malicious bacterium. After gluing erythrocytes, the test blood becomes thick and grainy.

Interestingly, even after complete healing from the illness, the reaction described above may give a positive result and shoot down doctors involved in the diagnosis of other infectious diseases.

Changes in the immune system of syphilic

So, the diagnosis of illness and control of its effective cure is a complex professional task. A patient without serious education in the field of medicine, it is impossible to understand the intricacies of analyzes and reactions.

Let's try simply and accessible to explain the development of changes in the immune system of the patient, and for how laboratory indicators it can be quickly identified in order to deliver the correct diagnosis in a timely manner.

Immediately after entering infection (pale treponama) in the human body, it faces immune cells. They immediately identify it as a foreign and dangerous microorganism, and begin to act.

In the blood of the patient, a week or month, antibodies appear, which have a specific impact on the bacteria of the pale treponam. They can be divided into two classes of antibodies.

The first testify that infection occurred quite recently (a week ago). The second suggests that the body has already reacted properly and formed its own defense, sustainable immunity from the disease.

Before the appearance of clinical symptoms of this disease in the blood of the patient, specific antibodies are detected. During treatment, the amount of antibodies is significantly reduced and gradually normalized. Formed persistent immunity to Trepleme in the future.

How to interpret the results of serology?

Today, most venereologists in their professional practice to diagnose syphilis are most often used by three reactions:

1) precipitation;

2) fluorescence;

3) hemagglutination.

If all three studies gave a negative result, it means that there is no infection, or the diagnosis was carried out before a certain period. Do it you need seven days after infection.

If all three studies have given a positive result, it means that the presence of a disease in the patient's body is confirmed, and should immediately begin its intensive treatment so that the disease does not exceed the chronic form.

If negative indicators also issued a precipitation reaction, then a patient has a late stage of treating disease, or therapy has already been completed. A positive result indicates the presence of antibodies in the blood.

If negative data is only at the fluorescence reaction, all studies should be passed again, because The likelihood is that they are carried out incorrectly and give false indicators.

If the positive indicators allowed only hemagglutination, it means that it is either false (conducted with a violation of the established rules), or was carried out after the end of the disease therapy.

If the positive indicators gave only the reaction of the fluorescence, this is either an early stage of illness, or carried out after effective therapy. If only precipitation gave a positive reaction, then the result of research is false.

Consequently, for the qualitative diagnosis of this complex infectious disease, only serology is not enough. For the setting of the right and final diagnosis, the entire complex of clinical studies and differential diagnosis is required.

Indirect methods for diagnosing syphilis.

For the diagnosis of syphilis, a variety of research methods are applied, differing in the technique of conducting and destination. Direct methods are aimed at detecting the causative agent in the material under study using microscopy (microscopy in a dark field, etc.) or PCR.

In addition to the methods of direct detection of pale treponama (T. Pallidum), with a survey on syphilis, indirect was widely used ( serological) Research methods that detect antibodies to the causative agent of syphilis in serum and cerebrospinal fluid. The indirect methods of diagnosis of syphilis include serological reactions of ELISA, RPGA, CER, RIF and RIF-ABS, Ribt, PCR, express method, immunoblot and others.

Serological methods for diagnosing infectious diseases.

Serological diagnostic criteria Based on specific antigen anti-antibody reactions. Antigens react (components of cell walls, flagellations, capsules, DNA and toxins) of those microorganisms that need to be determined with antibodies contained in serums. Between antigens and antibodies corresponding to them, binding occurs, which is based on the methods of serological diagnostics. Serological reactions are used to determine the unknown antigen (source of which is bacterium, virus, toxin, etc.) with a known antibody or to determine serum antibody with a known antigen.

Serological reactions are classified depending on the state of the antigen and the characteristics of the medium in which the antigen and antibody interact, as well as by the method of conducting.

For serological reactions, many laboratory methods are used, such as agglutination, precipitation, complemental binding, immunofluorescence, immunoferment and radioimmune analysis and others. These reactions make it possible to effectively carry out the preliminary identification of microorganisms.

Serums that are necessary for the formulation of serological reactions are obtained experimentally, in particular, they are produced by vaccines and sera institutions, and are offered as part of commercial diagnostic sets.

Serological methods are an important tool in the diagnosis and treatment of human infectious diseases and animals, since with their help, it is possible not only to identify the causative agent of the disease, but also to detect patients in the blood and speaking specific antibodies to the appropriate pathogens. Serological methods are currently the most effective methods of diagnostics at the impossibility or difficulties of excretion of the pathogen, and relatively rarely give false-positive and false-negative results.

Use of serological methods for the diagnosis of syphilis

The basis of serological laboratory methods for diagnosing syphilis is the body's ability to give an immune response to the appearance of the pathogen. With the help of serum serum reactions (plasma) of blood (or cerebrospinal fluid), traces of immune response to infection, namely antibodies to the antigens of pale treponam, or the antigens themselves.

In order to establish a specific nature of the existing clinical manifestations (i.e., that they are a consequence of Syphilis) and, in the future, control the dynamics of the pathological process, a large number of serological research methods have been proposed. The same methods are also widely used for screening of the population.

In accordance with the current national guidelines and clinical guidelines, in many countries of the world during public surveys in order to identify patients with syphilis and, when establishing clinical diagnosis, advanced serological methods are used. They are used both in the presence of clinical signs of disease in patients and in latent periods.

The formulation of serological reactions is one of the most reliable methods for diagnosing syphilis. Standardized serological reactions with a regulated method of formulation are called serological tests for syphilis. Considering that almost all serological reactions to syphilis under certain conditions may be false positive or false negative, they should be put in the complex and, if necessary, in dynamics.

Serological reactions that are used to determine the antibodies in the patient's blood serum differ from each other with sensitivity, specificity, complexity of production and cost. In addition to classical methods, immunological tests and technologies that have received a new impetus for development in the 21st century are used for the efficient serodiagnosis of syphilis.

Antibodies are detected by various immunochemical (serological) methods, including sedimentary reactions, immunoferment, immunohemyluminescent, immunochromatographic tests, linear immunoblotting, study using flow fluorometry, immunocipov technology and others.

Serodiagnosis (research using serological methods) is used for:

confirmation of the clinical diagnosis of syphilis,
putting the diagnosis of hidden syphilis,
control over the effectiveness of treatment, as one of the criteria for curable patients with syphilis,
syphilis Prevention (Screening Survey of certain groups of the population in order to identify pathology).

The most important properties necessary for serological tests - sensitivity, specificity, reproducibility

The decisive criterion when choosing a laboratory diagnostics method is its effectiveness - sensitivity, specificity and reproducibility.

Sensitivity - This is the proportion of positive results in patients. The sensitivity of the method is determined by the percentage of positive test results, obviously containing specific pathogen markers (NPRs, antigens of the pathogen or antibodies to them).

Specificity - The proportion of negative test results in healthy patients. The specificity of the method is determined by the percentage of negative results of the testing of samples, obviously not containing specific pathogen markers. Thus, the higher the sensitivity and specificity, the more reliable and the significance of the research method.

Important diagnostic criteria also applies reproducibility Results with repeated studies of the same samples. It should be noted that, despite significant achievements in the field of high technologies, there are no methods providing 100% (absolute) sensitivity and specificity in all the biocrix studied.

Currently, test systems, kits, ingredients with less than 95% sensitivity and specificity are officially registered in Russia. Thus, there is always the possibility of obtaining an inadequate result.

Classification of tests by type of antigen used. Treplen and improper tests for syphilis

In modern venereology, more than a dozen sifilis serological reactions are used for diagnostic purposes, which can be divided into different criteria for various categories. The classification is carried out according to the methodology of research, fields of application, speed, cheapness, requirements for laboratory equipment, etc.

Tremponium reactions are theoretically more specific, but they also give false-positive results. Moreover, they do not allow differentiate untreated and cured syphilis. The results of the tronewn reactions will be positive in both cases. Faplendose reactions allow you to distinguish between the untreated or recently transferred and cured infection.

During the examination, it is recommended to conduct a treponem, and a non-reaction. For installation and confirmation of the diagnosis of "syphilis", positive results are required during tests of both types - trepal and non-replete. Therefore, unnecessary tests are applied in combination with tronewhen tests, and are held before the start, in the process and after the end of treatment at certain time intervals.

1. Finding tests

The most famous of non-renewable tests with visual decoding of results is

RW - Vasserman reaction with lipid antigens (Complement Binding Reaction with CardioLipin Antigen, RSKC)
cannes reaction (not currently used),
cytochole reaction Zaks-Vitebsky (not currently used),
microreactment of precipitation with plasma or inactivated serum (MRP or RMP),
RPR (Quick Plasma Reaglees Test, Rapid Plasma Reagin),
TRUST (test with toluidine red and unheated serum, Toluidin Red Unheated Serum Test).

There are 2 tests with microscopic readings of the reaction results:

1. VDRL - (Venereal Disease Research Laboratory);

2. Usr - Test Definition of Active Reaglees Plasma (Unheated Serum Reagins).

Reactivity in non-dedicated tests usually indicates tissue damage and is not always specific to syphilis. Easy to perform and low cost allows them to be used as qualifying reactions when setting a preliminary diagnosis of syphilis.

2. Treponne tests

In the treppene tests, specific antigens with treponia are used. These tests are required to confirm the diagnosis (RPGA, RIT, Reef and IFA). They are more complex and expensive than the tests of the 1st group, but also more specific and sensitive. The detection of antibodies in the spinal cerebral fluid is also made using treponem tests.

Traditional tronewhen reactions confirming the diagnosis of syphilis requires expensive laboratory equipment and experienced personnel, so they are rarely held outside the specialized laboratories. However, now they can be replaced by simple and fast tronewn reactions that can be carried out on the ground and in which solid blood is used. Conducting these reactions does not require long-term training, special conditions for storing reagents and equipment.

Comparative cheapness, convenience and practicality of the tronewhen express reactions attract attention not only as a diagnosis confirmation methods. These reactions can be used to screening syphilis as part of the provision of primary medical care (they can be carried out in places, in the same medical and preventive institution) or in areas where laboratories are not available. However, since antibodies to T. pallidum are determined over a number of years, regardless of whether the patient was treated or not, the trepal express reactions cannot be used to assess the effectiveness of the treatment and differential diagnosis of untreated and cured syphilis.

Classification of serological methods of diagnosis of syphilis by type of antibodies

In modern dermatovenerology, various serological reactions to syphilis are used for diagnosis. Some of the methods that were relevant ten years ago, cease to be applied due to complexity or insufficient specificity. Depending on the detected antibodies, the methods of serological diagnostics of syphilis are divided into three groups:

I. Lipid (reactive) reactions - the antibodies for lipid antigens (reinquate) are determined:

1) Flocculation: microreactment on glass with lipid antigens - Express-method of diagnostic (microreactlation of precipitation - MRP), VDRL, CMF (Cardiolipin Microflocculation Test), RPR et al.;

2) Complement binding reaction (RSK) with lipid antigens: Vasserman reaction (PB), high-quality and quantitative method of setting, thermostat and cold (collers reaction);

3) sedimentary reactions that are currently not used: kana precipitation reaction, cytocholic reaction of Zaks - Vitebsk, etc.;

II. Group tronewhen reactions - antibodies to group traponem antigens (included in the microbial cell both pathogenic and saprophyte treponia) are determined:

1) RSK with protein antigen of the Reuters;

2) immunofluorescence reaction (reef);

3) immune sticking reaction (RIP).

III. Viospecific protein tronewhen reactions - define antibodies to specific species antigens Treponema Pallidum:

1) the reaction of the immobilization of pale treponia (rite);

2) the reaction of immunofluorescence reef-abs and its options (IGM-FTA-ABS, 19S-IgM-FTA-ABS, etc.);

3) the reaction of indirect hemagglutination of pale treponam (RPGA) and its modification of TPPA.

4) immunoassay analysis (ELISA);

5) Immunoblotting.

Practical use of serological reactions to syphilis

Various serological reactions are used for different practical purposes.

Abroad, with mass surveys of the population and, if necessary, the emergency detection of syphilis are used non-refined qualifying reactions (VDRL, RPR, etc.). For diagnosis, confirmation is required in reef-abs tests (FTA-ABS), RPGA or TPPA. Currently, it is recommended to use ELISA as a replacement VDRL in screening tests. This is due to the fact that the IFA test is characterized by sensitivity, specificity, the ability to automate research, as well as with the development of diagnostic test sets. In addition, the reversing scheme of the order of study on syphilis is justified when the first tests are used first.

In order to control the effectiveness of therapy and to assess the activity of infection, VDRL is recommended in quantitative execution. As a confirming / additional test, the IPA test is used on the IGM antibodies.

In domestic practice, a complex of serological reactions (CER) is used, comprising the microprocipation reaction (RMP) with a cardiolipin antigen and RSK with cardiolipin and treponem antigens. Recently, it is recommended to replace RSK to ELISA or RPGA. The reef (and its modifications - reef-abs and other), Ribt are also used.

Ribt is used as an examination reaction in cases of discrepancies of trepaline reactions.

Approaches to laboratory serological diagnosis of syphilis in the Russian Federation

The introduction into the practice of unified methods of clinical laboratory studies in the USSR and the Russian Federation made it possible to introduce more progressive diagnostic methods, streamline the work of clinical and diagnostic laboratories, improve labor productivity, reduce duplication of laboratory studies and has become the basis for the development of rational forms of finished reagent sets.

In 1985, in the USSR, in order to improve the diagnosis of syphilis, the unnecessary reaction of RSK with a non-specific (Wassermanmann) antigen and sedimentary reactions (cytochole and danga) were excluded from the diagnostic complex, as less sensitive and preventive information.

Instead of them, as part of a complex of serological reactions to syphilis (DSR), it was planned to use a complement binding reaction with treponem and cardiolipin antigens (RSKT) and microreactration of precipitation with a cardiolipin antigen (RMP). Higher sensitivity and informativeness of this complex of reactions ensured the detection of not only reacts, but also of bonded antibodies.

1985

1. RMP with a cardiolipin antigen with plasma of blood and inactivated serum. Selection test in case of isolated use.

2. RSK with treponem and cardiolipid antigens; Quality and quantitative methods of production, thermostat and in the cold;

3. The reaction of the immobilization of pale treponia (RIT); Tablet and luncture techniques of production;

4. Immunofluorescence reaction (reef) in the following modifications: reef with absorption (reef-abs) with serum and capillary blood, RIF-200, reef with solid spinal fluid (reef-c); Qualitative and quantitative methods of production. Diagnosis of hidden and late forms of syphilis, LPR recognition (false positive results)

5. A complex of classical serological reactions (CER): RCK (vasserman reaction) with cardiolipin and treponem antigens + RMP. Preventive examination of the population on syphilis, diagnosis of all forms of syphilis, control of the effectiveness of treatment, examination of persons contact with syphilis.

In 2001, a new regulatory document was approved by the Ministry of Health of the Russian Federation, regulating the procedure for conducting diagnostic tests - Order of the Ministry of Health of the Russian Federation No. 87 of March 26, 2001 "On Improving the Serological Diagnosis of Syphilis".

In order to improve the laboratory diagnosis of syphilis, improving the quality of work and the prevention of further dissemination of the incidence of syphilis, it is recommended to replace the RSK in the seroractivity complex (CER) in the diagnosis of syphilis on ELISA and RPGA as qualifying and confirming tests, since These test systems are highly sensitive, specific and reproducible.

Order No. 87 dated March 26, 2001 "On Improving the Serological Diagnosis of Syphilis" provides for the use of syphilis for the serm and liquorodiagnosis in Russia of the following methods:

1. RMP and foreign analogues (VDRL, RPR and similar microreacts) as qualifying tests during the survey of the population on syphilis. Rump formulation is carried out with plasma or inactivated serum.
2. Immuno enzyme analysis (ELISA). Antigen of culture or pathogenic pale trepoon. Diagnostic reactions, including for liquorodiagnostics. Due to the simplicity of the formulation and availability of commercial test systems can be used as qualifying tests.
3. Passive hemagglutination (RPGA) reaction. Antigen of culture or pathogenic pale trepoon. Selection and diagnostic reactions.
4. Qualitative and quantitative reef (reef-abs, reef-c, reef with capillary blood from the finger). Antigen - pathogenic pale treponema strain of Nikols.
5. A complex of serological reactions (CER) on syphilis, consisting of a complement binding response (RSK) with treponem and cardiolipin antigens, and RMP. It is possible to replace the complement binding response to ELISA or RPGA also in combination with RMP. CER refers to diagnostic tests.
6. The reaction of the immobilization of pale treponia (Ribt), in which pathogenic pale traponams strain Nikols are used as an antigen. Ribt belongs to diagnostic confirmation tests.

Thus, the sequence of examination of patients on syphilis in health facilities is recommended to be planned as follows:

1. With a primary examination, a qualifying (screening) reaction of microprocipatition (RMP) or its modification (RPR, TRUST, VDRL) in quantitative and qualitative variants is made and in case of a positive result - any specific confirmation of the tronewhen test (RPGA, IFA, DPF, Reef , Rit);

2. After the end of therapy is raised RMP or its modification and to reduce the titer judges the dynamics of the infectious process and the effectiveness of therapy. Confirmation of the effectiveness of the therapy is considered to be a reduction in the title in 4 or more than 1 year.

Admission by appointment! Saturday Sunday.

Reactive tests are used for mass examination of patients on syphilis. They are usually carried out within the framework of preventive inspections. Such tests are available in each medical institution and are held quickly. The answer is usually ready after 30-40 minutes.

A positive result when conducting reactive reactions is not a criterion for making a diagnosis. It is necessary to additionally conduct species-specific studies.

The most common screening method is the Vasserman reaction. When it is used, cardiolipin and treponem antigens are used. If there are no reacts in blood serum, then the hemolysis of the erythrocytes of the ram, which are added as an indicator.

In the presence of reacts, one-piece red blood cells fall into the sediment, in this case the reaction is considered positive.

Reactive in the following cases:

other diseases whose pathogens on antigenic structure are similar to pale spirochet
pregnancy
oncological diseases
receiving salicylate
myocardial infarction
technical errors when analyzing

With a positive result of the reactive reaction, specific serological tests are carried out. Also, they are prescribed if a negative result is in doubt.

Tremponem antigens are used in such analyzes such as Reef, Rit, ELFA, RPGA, the hematorsorption reaction in the solid phase. These reactions are based on the formation of antigen antibody complexes and differ by the method of their definition. The immunofluorescence reaction is most often used.

The drug is treated with luminescent serum, which allows identifying immune complexes under a luminescent microscope.

One of the most sensitive serological reactions to diagnose syphilis is RPGA. The method has high accuracy. It is often used to verify the diagnosis during pregnancy, when other analyzes can give a false positive result.

Features of serodiagnostics

For serological diagnosis of syphilis in different periods Blood fence from veins. The analysis is recommended for an empty stomach, it reduces the number of false positive results. The test tube must be sterile. When conducting express tests in some cases, blood is taken from the finger.

In case of suspicion for serodiagnostics, the spinal fluid is taken. For its analysis, the same techniques are used as in the study of blood.

For the diagnosis of syphilis, the full examination in our clinic passes.

Russian National Research Medical University. N.I.Pirogov

Department of Dermatovenerology Pediatric Faculty

Report on the topic: Laboratory methods for diagnosing syphilis

Performed: Student 440 in groups

Pediatric faculty

Searanov Igor Anatolyevich

Finding research

Tremponium research

Complex for serological reactions

Vasserman reaction

Immunofluorescence reaction

Imitation adhesion reaction

Pale Treplem Immobilization Reaction

Immunofluorescence reaction by adsorption of pale trepoon

Hemagglutinational reaction

Linked immunosorbent assay

Polymerase chain reaction

All serological methods of research that are applied to today are conditionally divided into two types: frameless, qualifying (NTT) - and tremponenwhich confirm the presence of the pathogen (TT). Sofilis proceeds very difficult, the clinic is very blurred and is not always manifested, therefore several serological tests are used for the ruling of correct diagnosis. With visual confirmation of the presence of the presence of a pale flutter (with the help of a microscope), the diagnosis is made immediately, and the remaining tests are rare.

Finding research (Tests) - NTT are the so-called qualifying studies, they are not very expensive and in their help you can examine a sufficiently large number of patients, besides, the results are ready for many tests very quickly. But with a false course of the disease, with low sensitivity, such tests are inappropriate, 100% result will not be able to obtain.

When conducting non-renewable tests in the material that is investigated, antibodies that react with cardioLipin - lecithin antigen. One of the first tests was a method based on the Immunological reaction of the Bordean - Gengu, where the liver extract of a newborn baby was performed as an antigen, who died of syphilis. For today, when conducting such tests, the antigen acts lecithin, Cholesterol and CardioLipin.

Abroad, in particular, 4 non-mining methods are used in the United States, which are divided into two types: methods that allow you to visually determine the results of the reaction (RPR and TRUST) and methods of microscopic reading of results (USR and VDRL).

Frameless diagnostic methods refers indirect linked immunosorbent assay Using cardiolipine as an antigen. In our country and in the CIS countries, plasma reaction is acting as non-refined tests. inactivated serum (mr) and the reaction at which the compliment is bonded with cardioLipin (RSK).

All methods of unnecessary diagnostics are very similar to each other. They have low cost, they simply and quickly spend. These types of tests are not suitable in identifying the disease at the primary stage and during syphilis, which flows secretly (Latent form of syphilis). Antibodies that are defined by a non-refined test appear, somewhere a month after infection of the trepal. In most cases, patients who treated the primary stage of syphilis, about about a year, non-negative results have a negative result.

Tremponium research (Tests) - TT are much more expensive, the technique of conducting them is very complex and they are used to confirm the positive results that were obtained with non-refined studies.

As we talked above tremponium methods Used in order to confirm the presence of pale treponam in the body, which was detected using non-dedicated tests. They also conduct them if the analyzes have not gave a positive result, but the clinic suggests the presence of a disease. After the complete cure of syphilis, more than 80% of the cured, the positive response is observed during carrying tests for several more years, and some have a lifetime. Based on this, the tronewhen tests are not used for preventive inspections in people who have passed a full course of treatment.

Scientific research in the field of immunology and molecular biology continues continuously and with the help of the latest technologies, all new tests appear for the diagnosis of syphilis, which firmly occupy leading positions. One of these tests that firmly entered into practice - immuno enzyme analysis (ELISA)And many research methods are at the stages of development.

TOT complex of serological studieswhich is carried out in Russia includes a comprehensive conduct of serological reactions:

standard serological reactions -

complement Binding Reaction (Vasserman Reaction),

reaction with a treponem antigen and a reaction with cardiolipin;

group tronewhen reactions

immunofluorescence reaction (reef)

immune sticking reaction (rip);

vidospecific protein tronewn reactions -

immobilization reaction Treplem (RIT),

Reef - ABS and its options (IGM-FTA-ABS, 19S-IGM-FTA-ABS),

reaction of passive hemaglusion by Treplem (RPGA).

If serological reactions are used in the complex, it will give the opportunity to identify the disease in the early stages of the disease.

The reaction of the Vasserman is the method of binding complement. To carry out the reaction, extracts are used as an antigen, which are made of pale treponia (specific antigens) and cardiolipin is an extract prepared from the heart muscle of the bull (nonspecific antigens). The larger in the material under study, there is a pale trepoon, the greater the degree of the disease and evaluate the degree of pluses:

1) - negative; 2) + dubious; 3) ++ weakly bed; 4) +++ positive; 5) ++++ convertible.

Vasserman reaction (Complement Binding Reaction) In mandatory, they are carried out with sedimentary reactions - Zaks - Vitebsk and Kana. The immunological nature of reactions, in general, the same as in the Vasserman reaction, but for these reactions requires more saturated antigens, which, when entering the reaction with serum reacts, give a greater sediment. Seronegative primary syphilis put if standard serological reactions gave a negative result. Detection of syphilisa the Vasserman reaction is effective in seropositive secondary syphilis, here the test results are 100% true.. At the tertiary stage of active syphilis, the results are true in more than half of the patients, and at the last stages of syphilis, with the defeat of the internal organs and systems, the results are correct by half of the patients. W. patients with early innate syphilis serological reactions give a positive result almost always, and in patients with late congenital syphilis - almost in 80% of cases.

The principle of RSK lies in the fact that the reacts that are in the blood serum patients with syphilis have a property to enter into compounds with different antigens. The resulting complexes sort the complement introduced into the reaction. For the indication of the complex, the antigen-complement complex uses a hemolytic system (a mixture of hemolytic serum erythrocytes). In the presence of the complex, the red blood cells fall into the sediment. What noticeably not armed with the eye. The severity of hemolysis is denoted by the doctor's keys: sharply positive 4+, positive 3+, weakly bedding 2+ whether 1+ and negative. In addition to a qualitative assessment of these reactions, there is a quantitative, which is in the diagnosis of some stages of syphilis and when monitoring the effectiveness of therapy

Immunofluorescence reaction (reef) Based on the detection of antibodies that are lined with a special fluorescent solution, in order to reveal the antibody antigen in the purple rays of the quartz lamp. This reaction has a high sensitivity and helps to identify the disease at the primary stage of sernegative syphilis. Also, it is this test that helps to identify the disease in patients whose disease flows latent or in later stages. There are several types of reactions such and the most highly appreciated RIF-200, with the help of which the hidden syphilis can be detected and recognize the non-specific results of the CER. But, despite the high RFA-200 rates, the diagnosis is occurring after all clinical analyzes. Reef is not suitable for observation of patients after complete treatment.Since it is quite slowly negativated at the treatment stage.

Immunal adhesion reaction (rip). The basis of this reaction is the adhesion of treponia, which are sensitized by serum, to red blood cells and precipitate them. Results are evaluated by the following table:

Negative - 0-20%

Dubious-21-30%;

Weak-bed and 31-50%;

Positive-51-100%.

For all indicators, Rip is very similar to Reef and Rit. This reaction is carried out in several cases, if, on the basis of clinical manifestations, anamnesis, syphilis laboratory studies is not confirmed, to control the disease after obtaining the necessary treatment and to confirm the results of the CER.

Pale Treplem Immobilization Reaction (RIT). Paps on Wednesday, where there are immobilizes of test serum and an active complement, pale treponams lose mobility. This reaction is based on this. RIT is very specific and used to recognize hidden syphilis, for the diagnosis of pregnant women who suspected syphilis and many other cases, in which standard serological tests are few specific. The big drawback of this reaction is that it is very expensive and its holding is a very complex process. The results are read by percentage data of the immobilization of pale treponia:

Negative - up to 20%; -Comnual -21-30%; -Labo positive -31-50%; -Nost -51-100%.

Due to the fact that immobilizins appear in the blood later than other antibodies, the reaction becomes positive a little later than when conducting other reactions. At the initial stage of infection, as a rule, a negative or weakly-bed reaction is observed. At the secondary stage of syphilis, although the appearance of serum immobilizins in the patient is observed up to 60%, the reaction is positive in almost half of the studied. With a relapse of the secondary stage of syphilis RIT, almost 90% of patients are positive. In the tertiary stage of the development of syphilis, with the damage to the internal organs, including the nervous system, when the Vasserman reaction gives negative results, the reaction of immobilization of pale trepunia is positive in almost 100% of patients. At an early stage of congenital syphilis, the reaction has a positive result in almost all patients, and in the late stage of the innate syphilis - almost 100% of patients. Seropositive latent syphilis is confirmed only after the rhythm, which is carried out after receiving positive results during other serological reactions. RIT is not used to control the disease in patientswho received the necessary treatment.

Immunofluorescence Reaction with Pale Tremponus (FTA-ABS).If the reaction is carried out for a patient, which is sick with syphilis and was not treated, then this reaction gives a positive result. Also high likely to identify infection with FTA-ABS at the very beginning of the disease.. The reaction has great sensitivity and specificity. To diagnose latent syphilis and in cases where several tests have already been conducted and they showed a negative result, but the clinic speaks about the infection of pale tronamed, in such cases the diagnosis is made frequently based on the results of FTA-ABS. Literally a week after the pale treponema fell into the body, the specific IGM antibodies begin to produce, which over time cease to appear and after 2 years are no longer determined. In order to understand whether the proposed treatment does the effect, conduct special tests that determine the specificity of these antibodies. There are several such tests today, but their conduct is too expensive, therefore, for most patients, these tests are not conducted.

Hemagglutinal reactionwhich defines specific antibodies to pale treponime (micro-RPGA). For this reaction, treponema is used as an antigen, so this reaction is very specific and delivering the results in most cases.

Immuno enzyme analysis (ELISA) One of the most specific to the diagnosis of syphilis. Today, most often use an indirect version of the ELISA. The advantages of this research method are obvious: not too much cost, the ease of conduct is sufficient, the high accuracy of the result is sufficient, with the help of this analysis, syphilis can be revealed at an early stage, the rapid obtaining results.

Based on method of immunobloting It is an immuno-enzyme analysis, which is combined with electrophoresis. It is one of the most specific analyzes and with its help is confirmed by syphilis infection.

Polymerase chain reaction (Specific research method) Conducted to establish a diagnosis with hidden flows of syphilis infection. When conducting PCR in the subject material, the pathogen is found, even at the initial stage of the disease. The detectable genetic material with DNA is divided and thus detect the pathogen becomes very simple. With neurosimifilis, when to identify the infection is very difficult when conducting other tests due to very low sensitivity, with congenital syphilis, at the primary stage of sernegative syphilis and for the diagnosis of HIV-infected, PCR is indispensable. Study spinal fluid Syphilis is carried out if there is clinical damage to the nervous system at an early stage of the disease, with hidden form and necessarily before the start of treatment. Also, this analysis is prescribed for neuralifilis patients in the later stages of syphilis and with latent form. The clinical laboratory conducts a study of cytosis, protein content, Pandi and Nonn - Apert's reaction. Vasserman reaction is carried out in serological laboratories, the reaction of Lange, Reef, Reef, Reefc, Rita.

Syphilis Multical. Infection, falling into the body, leaves traces not only on the skin and genitals, but also destroys the nervous system, the musculoskeletal system, lungs, worsens hearing and vision. Despite the wide range of symptoms and variants of their combinations, doctors have learned to identify the disease and accurately indicate the stage of its development.

Society wants to protect against the infection of pale trepalia. Therefore, there is a number of express tests for early diagnosis of syphilis or identifying carriers of infection. The rule was the blood fence to laboratory diagnostics:

in cases of pregnancy;
before surgery;
donors before blood or bodies for transplantation;
medical workers, teachers, educators, public catering workers, etc.;
in military personnel;
at prisoners.

Laboratory test and clinical examination at syphilis will hold for:

patients with signs of STDs;
sexual partners and other members of the family of a person with a diagnosis of "syphilis";
babies born from a sick mother;
all who have a diagnosis of another sexually transmitted disease;
verification of the effectiveness of the therapeutic method during treatment;
all who have screensing a positive result.

The procedure for detecting an infection at the reception at the venereologist

From the conversation with the patient, the doctor finds out:

is there a confirmed diagnosis of "syphilis" by a partner;
whether there were previously rashes on the genitals;
whether lymphatic nodes were infected;
did you have a place unprotected sex 3-4 weeks ago.

During the clinical inspection of the skin, genital organs, anus, mucous membranes, a specialist finds out the similarity of rash and other lesions of the skin with those characteristic of syphilis. Peripheral lymph nodes are carefully palpable to assess their extension.

In cases of syphilide (solid Shankra, Roseola, Papul, Granulul), the doctor prescribes a histomorphological study. The laboratory describe the appearance and study the contents of education. According to the results, judge the stage of the disease.

The decisive contribution to the diagnosis of syphilis makes a laboratory method for identifying the pathogen or traces of an immune response to infection.

The diagnosis is determined based on the set of data obtained after the clinical examination and laboratory tests. In exceptional cases, when it is impossible to conduct analyzes, the treatment is prescribed on the basis of inspection.

Diagnosis of complications

Secondary and tertiary syphilis can provide complications called specific visceralites. All organs and systems can be included in the process, but most often venereologists are observed by lesions:

liver;
nervous system;
bones;
hearts.

Sofilis for pregnant women is especially dangerous. In addition to complicated pregnancy, the intrauterine or vertical (in the birth path) infection of the fetus, stillbirth is not excluded.

It is important to diagnose not only infection in time, but also secondary diseases. For this purpose, in addition to specific tests and general analyzes of urine and blood, additional surveys are conducted (table).

Laboratory tests of biological materials

The laboratory diagnosis of syphilis began to be developed since 1905, when the causative agent was discovered - pale treponema. Prior to this, the contents of Syphilide infected rabbits that are absolutely sensitive to infection. Already in 1906, the first serological response to syphilis (RW) was developed by Wasserman. In 1949, medicine proposed a more specific reaction of the immobilization of pale treponam (Ribt), but RW is not displaced from laboratories to today.

Modern diagnostic methods come to replace the first analyzes. They differ in the technique of holding and destination. In the list of current tests:

damnopol microscopy - provides for the study of a smear or scope for detecting treponam in the substrate under study (in everyday life, this study is sometimes called the "smear to syphilis");
molecular biological methods for detecting specific DNA (polymerase chain reaction, DNA sensing);
serological diagnosis of syphilis on serum or spinal fluid.

Damnopol microscopy

From the lesions of the lesion take samples for a microscopic study on pale trepony. Test objects are:

the contents of the syphilide;
fabric liquid;
likvor;
amniotic fluid;
pupil fabric.

Treplema received the characteristic of the "pale" due to the resistance to the action of most dyes. Live microbe is clearly visible in a dark field with a special backlight. The laboratory assignment to the morphological signs of bacteria and watches the character of their movement.

For histomomorphological research, the samples are painted silver (by Morozov) or by Romanovsky Gymzea.

Direct microscopy methods are used to diagnose a congenital disease or later stages of syphilis. To check its correctness can be a direct reaction of immunofluorescence (RIF-TP) or polymerase chain reaction (PCR). In the first case, the antibodied antibodies and fluorescent dye helps to identify the pathogen, and in the second - the DNA molecules of the pale treponama.

Search for DNA pathogen

Even the only DNA molecule can be detected when analyzing blood. Successes in the art became possible since 1991, when the test of the polymerase chain reaction (PCR) was invented. The carrier of hereditary information is propagated in special temperature conditions and repeatedly copied by the enzyme - the DNA polymerase. After, the method of electrophoresis, the desired fragments of the chain are detected.

This is a completely accurate and specific test. Abroad, he became a gold standard of diagnosis of syphilis. In Russia, PCR is still more research than clinical.

Another method is detected by treponams for DNA sensing (hybridization of nucleic acids). In this case, denatured DNA is connected to a specific probe. Changing the color of the filter to which the samples are applied indicates infection.

Serological diagnostic methods

For various diagnostic purposes, serological unrepressive and tronewable tests can be used. During the analysis, antibodies are revealed to the pale treponema in the blood.

As rapid diagnostics or screening, it is recommended to refer to the following non-refined tests:

RPR - fast plasma reacts test (Rapid Plasma Reagins);
RST - Reagree Single Test (Reagin Screen Test);
TRUST - test with toluidin red and unheated serum (Toluidin Red Unheated Serum Test);
Usr - test of the definition of active plasma reacts (unheated serum reagins);
VDRL - Laboratory for the study of venereal diseases (Venereal Disease Research Laboratory);
microreactment of precipitation (MRP) with plasma or inactivated serum;
communication reactions of complement (RSK) and its varieties with a cardiolipin antigen (RSCK).

The methodology is based on antibody search (IgM and IgG) to lipids of damaged cells and lipoproteins of the pathogen membrane. Positive response These analyzes are shown a week after the first syphilide.

Antibodies actually detects methods:

ELISA - Enzymelynked Immunosorbent Assay;
FTA - Immunofluorescence reactions - Reef (Fluorescent Treponemal Antibody);
RW - Complement binding reactions (Vasserman reaction);
RW with a tronewhen antigen - RSKT;
TPHA - Passive hemagglutination reactions - RPGA (Treponema Pallidum Haegglutination Assay);
TPI - reactions of immobilization of pale treponam - Ribt or Rit (Treponema Pallidum Immobilization Test);
Western blot - immunoblotting.

Venenologists follow a certain procedure for conducting serological tests. One of the unrepressive analyzes is carried out as express diagnostics. Low sensitivity is taken into account in early and late stages of infection. Therefore, both negative and positive responses with a certain clinical picture must be rechecked by trepal methods.

In different life situations, there may be a combination of positive and negative answers. The table will be decrypted.

The final conclusions make a venereologist on the basis of a data complex: a clinical picture, histological and laboratory studies.

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