Blood on the reaction of Wasserman equipment. When is a false positive test for syphilis possible? Dynamics of the Wasserman reaction

Representing a constantly improving procedure for identifying treponema pallidum in the body, the Wasserman reaction makes it possible to detect syphilis in a timely manner and begin the necessary therapeutic intervention, which will prevent the possibility of developing undesirable consequences for the patient’s health. The peculiarities of such a diagnostic operation also make it possible to monitor the course of treatment, classify the degree of effectiveness of the selected methods and make the necessary adjustments to achieve faster and longer-lasting positive results.

The analysis is based on studying the composition of the patient’s blood, which during the period of infection with Treponema pallidum is induced by a significant amount of antibodies to this pathogen. The Wasserman reaction allows, with the help of a special substance (cardiolipin antigen, which is synthesized exclusively in the laboratory), to detect the body’s reaction to a given pathogen and draw up a scheme of influence. Venereologists know about the high degree of effectiveness of the Wasseramann reaction, which is why this diagnostic method is used to identify such a serious and dangerous lesion to human health as syphilis.

What is the Wasserman reaction

An analysis for syphilis carried out using the Wasserman reaction provides doctors with the most complete information about the patient’s health status in the presence or absence of antibodies to Treponema pallidum in the blood. This research method also makes it possible to approximately determine the time of infection, which is important for determining the likely circle of infected individuals.

Such a diagnostic analysis allows, in addition to prescribing adequate treatment, the necessary prevention of syphilis. Blood, which when infected contains a large amount of antibodies to the pathogen, “reports” the degree of infection and the period of development of the infection, which is important for drawing up a treatment regimen, choosing medications, their dosage and duration of use.

Why do such an analysis?

To detect the presence of a disease such as syphilis, as well as to prevent it and control the quality of treatment, a procedure is used - the Wasserman reaction. Venereologists use it both to determine the presence of Treponema pallidum in the blood and to record the time of infection. The maximum information content of the analysis, the relative ease of execution and the accuracy of the results have made the Wasserman reaction a frequently used method for diagnosing syphilis. The diagnosis made as a result of its use does not require clarification.

The Wasserman reaction is performed in case of suspected syphilis infection, during unprotected sexual intercourse, or in the presence of this dangerous disease in the mother: syphilis can be transmitted from an infected pregnant woman to her child. Since the diagnostic procedure is highly informative, it is also used to obtain reliable data about the time of infection and for prevention in the listed situations. Control of treatment and its effectiveness are also determined during the Wasserman reaction, which makes it possible to correct the treatment process if it is insufficiently effective.

The frequency of performing the diagnostic procedure in question is determined by factors indicating a possible infection with syphilis, if there is a suspicion that the treatment is not effective.

The video below will tell you more about Wasserman’s reaction:

Types of such a procedure

There are no varieties of the Wasserman reaction. The methodology for performing this diagnostic procedure is standard, the application depends only on the goal: identifying existing damage to the body by the syphilis virus, which is transmitted sexually and from an infected woman to a child during pregnancy, treating it or preventing it during unprotected sexual intercourse.

Indications for testing

Indications for the use of the Wasserman reaction procedure are suspicion of syphilis infection and monitoring of treatment. If it is necessary to clarify the diagnosis (this research method in some cases gives a false positive answer due to the presence of a certain amount of virus antigen in the blood of any person), the repeated Wasserman reaction is also used.

The analysis is taken for dermatological problems, such as:

The following conditions and situations are also considered indications for the use of the research method in question:

• the period of gestation due to the high probability of infection of the fetus with a sexually transmitted disease, early miscarriage, and the likelihood of developing organic pathologies in a newborn child;
• when working in close contact with the population - medical and social workers, merchandisers and sellers;
• if you suspect;
• before ;
• when planning pregnancy;
• for alcoholism and drug addiction;
• when admitting a patient to a medical institution - neurological, psychiatric;
• before and ;
• when hospitalizing a patient who has signs or suspicion of syphilis infection;
• if you suspect;
• before the blood collection procedure for donation.

Also, blood is taken for the Wasserman reaction when there is a threat of miscarriage for unknown reasons, when the body temperature rises with parallel inflammation of the lymph nodes.

Contraindications for use

There are no contraindications to the Wasserman reaction. However, there are a number of factors that can distort the final result of the analysis, therefore the Wasserman reaction should be carried out in their absence. Such factors that provoke a false positive result include:

• the first two weeks after birth;
• period of the first trimester of pregnancy;
• presence in the body;
• high body temperature;
• inflammatory processes occurring in the body;
• pneumonia;
• diabetes;
• tuberculosis.

The listed situations most often cause a distortion of the obtained result of the reaction to detect syphilis, therefore, if they are present, you should not take blood for analysis.

Method safety

The procedure for taking blood for analysis is absolutely safe, since a sterile instrument is used and the standards for taking blood from a vein are observed.

Preparation for the procedure

Before taking blood for analysis to carry out the Wasserman reaction, you should not drink alcoholic beverages, do not smoke, do not eat fried, spicy, smoked foods for several days (3-5) before the blood is taken, and, before the reaction itself, completely abstain food. Blood donation for the Wasserman reaction is carried out strictly on an empty stomach, otherwise the result is highly likely to be false.

Features of the event

To take blood for the Wasserman test, the ulnar vein is used in adults and the occipital vein in infants. In newborn babies, a blood test may also be taken from a small incision in the heel.

For blood sampling, the patient sits on a chair or lies on a couch. In order to make it more convenient to get the needle into the vein, the hand is developed - with the vein tied with a rubber tourniquet, the hand is clenched and unclenched with a rubber ball, or the patient clenches and unclenches his fist.

Next, a doctor wearing rubber gloves takes blood with a sterile disposable syringe, which is immediately sent for analysis. If it is not possible to carry out the analysis as quickly as possible, the blood is placed in a freezer with a temperature range of -3 - -5°C.

The patient does not experience any significant pain during blood sampling. The procedure lasts about 3-6 minutes. If necessary or dizzy, the patient is asked to lie on the couch for as long as possible to fully regain consciousness and come to his senses.

Decoding the results

After the procedure for taking blood from the ulnar vein in adults or the vein at the base of the skull in children, the decoding is carried out by the doctor who issued the referral for the analysis. In general, the decoding looks like a set of plus signs that indicate the degree of likelihood of an infection in the patient’s body.

• With one plus the likelihood of having syphilis is minimal,
• with two pluses- barely positive
• at three- positive,
• A with four pluses- extremely positive.

However, when receiving the result of the analysis, you should not diagnose yourself, since the number of pluses should not always be regarded as the final result. When making a diagnosis, a doctor takes into account not only the pluses obtained during the analysis, but also the presence or absence of concomitant manifestations of the disease.

A false positive result can occur in the presence of concomitant current lesions in the body, during pregnancy and immediately after childbirth, as well as in the presence of malignant and benign neoplasms in the body.

Wasserman reaction scheme

average cost

A diagnostic procedure such as the Wasserman reaction is carried out in almost every medical institution if it has its own laboratory. The duration of the analysis depends on the number of workers and the distance of the laboratory.

The quality and accurate result of this analysis does not always depend on the cost of the procedure. In a private medical institution, the price of the analysis will be higher than in a public institution, where such an analysis can be done free of charge under a medical policy. On average, testing for syphilis (Wassermann reaction) costs from 580 to 1650 rubles.

The video below will tell you how to test for syphilis at home:

The Wasserman reaction, successfully used for diagnosing and monitoring the effectiveness of treatment of syphilis, is widely used in mass examinations of donors, pregnant women, employees of educational institutions, trade and public catering.

Wasserman reaction - how to get tested?

This analysis is one of the main serological studies. It is recommended to donate blood for analysis on an empty stomach. This is due to the fact that consumption of alcoholic beverages and fatty foods may affect the accuracy of the results obtained. Blood is drawn from both a vein and a finger.

Wasserman's false reaction

The Wasserman reaction is based on the production of antibodies by the immune system in the blood serum of a sick person. Antibodies are detected as a result of laboratory testing of the antigen - cardiolipin. The reaction is considered positive if antibodies are detected in the blood sample being tested. However, there are frequent cases of the so-called false-positive Wasserman reaction. This is due to the paradoxical reaction of the human immune system, when the immune system begins to fight the cells of its own body. It is with this scenario that the same anti-lipid antibodies are tested in the blood as with syphilis.

Causes of false positive Wasserman reaction

According to statistics, such results occur in 0.1-2% of cases of the total number of studies. Possible reasons could be:

• viral infections (hepatitis, intestinal infections, malaria,);
• systemic diseases (lupus erythematosus, dermatomyositis, scleroderma and others);
• cardiac inflammatory diseases;
• pregnancy;
• blood diseases;
• taking alcohol and drugs.

The false-positive Wasserman reaction in some of the listed cases may become negative after a certain long period (a year or more) even without any treatment.

Diagnosis of a false positive reaction Wasserman during pregnancy is a stress factor for a woman preparing for motherhood. To exclude an erroneous diagnosis in such cases, a repeat serological test is recommended, which is carried out 2 weeks after the first. Treatment can be prescribed only after a sharply positive reaction has been re-established.

As a rule, a nonspecific serological reaction in most cases is weakly positive. It should also be taken into account that the detection of a weakly positive Wasserman reaction may also depend on the methodological purity and technique of conducting the study.

In 2011, at the 12th week of pregnancy, I took tests at the residential complex in Kiev. And then it turns out that RV gives +. Without explaining anything, I was sent to the skin dispensary at my place of registration (Kirovograd). At the same time, having already read everything on the Internet, I am going with the firm intention that I will not consent to a course of antibiotic treatment. My husband is the only man, and he is 100% healthy (he undergoes a commission every year). I got to an adequate doctor, who decided to immediately examine me and not send me to the hospital. I also took a smear -, microreaction -, RV+, RIF -. At the same time, the husband was also fully examined - everything was negative. She gave me a certificate stating that this was some kind of seropositive reaction during pregnancy. And so every month before giving birth I went to her for tests. All my results were repeated, just like the first time (once, however, RV gave ++). I won’t tell you what I went through during that pregnancy, when in Kyiv they didn’t want to register me, and at my place of registration they looked at me like I was a leper. But in the maternity hospital, after looking at the certificates, no one asked anything, and I gave birth like everyone else...
After giving birth, I did not have the opportunity to retake tests at my tannery (we immediately left for Kyiv). It was agreed with the doctor that at the first opportunity I would come and take everything again. But 2 years have passed. I was sure that everything would return to normal and the tests would become negative. But it so happened (I took tests in Kursk) that again RV gives ++. I went back to the Internet in tears and found information that even during lactation this test can give a false positive result. I finished breastfeeding (1 year 10 months) literally a week before the test. And a week ago I went to Kirovograd. I passed RV ++++, RIF and RPGA + (but said that this was accepted as negative). I do not know what to do!!! The doctor ordered repeated tests, if the results are the same again, you will need to go to Kharkov (they do some kind of analysis there that will definitely put everything in its place).
1. What could be the reason that my RT results fluctuate so much?
2. How might these tests behave in future pregnancies?
3. Could I somehow have gotten sick with syphilis (I don’t even know how I could have gotten infected) without noticing anything (I wasn’t treated with antibiotics at all!)? At the same time, everything is negative for my husband.
4. If it really is syphilis, what should I do with my daughter - should she also be examined? Most of all I fear for her health!

Wasserman reaction - compliment binding reaction

The Wasserman reaction is a method for detecting antibody proteins to treponema pallidum (the causative agent of syphilis) in the blood serum of a person being examined. The Wasserman reaction is a method that often lacks specificity, which is why in many modern clinical laboratories it has been replaced by a more modern one - the anticardiolipin test.

Treponema pallidum, antibodies to which are detected during the Wasserman reaction, when entering the human body causes a severe systemic disease - syphilis. The difficulty of diagnosing it lies in the variety of symptoms that appear, which is caused by damage to almost all systems and organs of the patient. Syphilis is, as it were, “masked” under the guise of diseases completely unrelated to infection - neurological diseases, heart diseases, musculoskeletal system or skin diseases.

The complexity of the clinical diagnosis of syphilis has led to the fact that almost all patients admitted to hospitals for routine or emergency treatment are examined using the Wasserman reaction or its analogues. In addition, pregnant women also undergo mandatory blood testing, this is due to the fact that syphilis of the expectant mother leads to severe disturbances in the development of the fetus. Children born to sick women are also infected with Treponema pallidum in utero; their syphilis occurs in a form that is much more difficult to treat. Fortunately, timely diagnosis makes it possible to detect infection at the earliest stages in both women and men, and timely treatment is the key to complete recovery from syphilis.

Wasserman reaction technique

One of the stages of the test is centrifugation

For the reaction, the patient's venous blood is taken, which is then processed in a centrifuge. The resulting liquid located above the precipitate that appears is called blood serum, and it is this that is studied in the Wasserman reaction.

In a simplified way, the reaction itself can be represented as the addition of an active substance to the patient’s blood serum, similar in composition to the surface membrane of Treponema pallidum. In addition, an indicator substance is added to the serum, which is destroyed during the reaction and gives a uniform color if the patient's blood serum does not bind to the active substance. Such binding occurs if the patient’s blood initially contained antibodies (immune proteins) to Treponema pallidum, that is, the human immune system “fights” it.

Indications for the study

A test is required for people planning pregnancy

Indications for the study are primarily contact with a person with syphilis (including household syphilis), as well as a planned or existing pregnancy. In addition, very often the Wasserman reaction is carried out in advance before planned operations or admission to a hospital, rehabilitation center or nursing home for the elderly.

In addition, there are a number of symptoms, in the presence of which it is worth getting tested to rule out infection:

1. Rashes on the skin in the form of light spots and “stars”;
2. Pain and swelling in the genital area;
3. The appearance of unusual discharge from the genitals;
4. The presence of a hard chancre on any part of the body (most often located in the genital area, in the mouth), a chancre is an ulcer or a kind of “pimple”, which is significant in size, but at the same time painless.
5. Increased body temperature not associated with any painful manifestations;
6. Pain in the arms and legs (when there is no disease of the musculoskeletal system);
7. The appearance of lumps under the skin in the groin area, under the armpits or on the neck, behind the ears or under the jaw, similar to small balls when palpated.

Preparing for the study

Patients need to familiarize themselves with the preparation rules

The analysis is very sensitive, so the number of potential “interferences” in its implementation should be reduced so as not to cause a false positive result. The main rules of preparation include:

1. The test should be taken strictly on an empty stomach; alcohol consumption and overeating are excluded a few days before the test.
2. You should not smoke before the analysis; you should stop taking medications 8 hours before the test, unless there are contraindications to this.
3. Women should donate blood only after menstrual bleeding has stopped.
4. Patients suffering from constipation should normalize intestinal activity 1-2 days before donating blood.
5. If you have an acute infectious disease, it is worth postponing blood donation for several days, preferably until the temperature and general blood test parameters normalize.

Analysis during pregnancy

Pregnant women need to undergo the Wassermann reaction

All women who register at the antenatal clinic for pregnancy are sent to donate blood for syphilis. This is due to the fact that Treponema pallidum easily overcomes the placental barrier and infects the fetus, causing systemic damage to organs and tissues in the unborn child.

However, it is during pregnancy that there is a high risk of a false-positive Wasserman reaction. This is due to the fact that a large number of “non-standard” immune system proteins circulate in the blood of a pregnant woman, appearing due to the increased load on the body. Any of these unusual proteins can accidentally react with the active substance of the Wassermann reaction, which is why diagnosing the disease in pregnant women is very difficult.

False-positive Wasserman reaction. Causes

The result may be false positive

The main reasons for a false-positive reaction are atypical antibodies (immune system proteins) circulating in the blood during pregnancy, as well as the presence of severe diseases of an infectious and non-infectious nature, as well as the associated use of highly active drugs.

We list the main diseases and conditions of the body in which the likelihood of a false positive reaction greatly increases:

1. The period 1-2 days before the start, as well as menstruation itself in women of childbearing age, pregnancy;
2. Taking contraceptives, analgesics, blood pressure lowering agents, most antibiotics;
3. Autoimmune diseases (systemic lupus erythematosus, Hashimoto's thyroiditis, rheumatoid arthritis, antiphospholipid syndrome);
4. Oncological diseases (usually with leukemia);
5. Tuberculosis infection;
6. Malaria;
7. Scarlet fever;
8. Lyme borreliosis;
9. Any infectious diseases accompanied by a pronounced rise in temperature.

False negative reaction: reasons

Taking medications can lead to a false negative test

A false negative reaction is not so common; in most cases it is due to reduced activity of the immune system. This condition is observed when:

• Congenital immunodeficiency;
• HIV infection (especially at the stage of developing AIDS);
• Oncological diseases and their therapy;
• Condition after massive surgical interventions, injuries and burns;
• Treatment with immunosuppressive drugs (glucocorticoids);
• Advanced stages of syphilis.

In addition, it is worth remembering that for infection with syphilis there is an early period in the development of the disease, during which it is almost impossible to detect it using the Wasserman reaction. In most cases, it is at least 6 weeks, and it is best to donate blood again no earlier than 8-10 weeks after the suspected infection to improve the accuracy of the results.

What to do if the test result is positive

Correct interpretation of the test - the correct diagnosis

A positive result does not always mean infection with the causative agent of syphilis, but it may indicate the presence of other serious systemic diseases. If you receive such a result, you should contact your doctor as soon as possible for further examination. In most cases, this will involve repeat blood testing in the same reaction or using more modern and accurate methods.

Content

Syphilis is a common sexually transmitted disease, if it is not detected in time, the body will suffer serious damage and death is possible. The Wasserman reaction is a special analysis that should be done if this pathology is suspected; timely diagnosis will help to immediately cure the disease if the result is positive. You can become infected with syphilis not only through sexual contact, but also through household items, hygiene products, and bedding.

Methods for diagnosing syphilis

Tests should identify the main causative agent of the disease - treponema pallidum, also known as treponema pallidum. To do this, blood is drawn on an empty stomach for serological analysis. Such a study is considered to be the main type of laboratory diagnostics for detecting syphilis. The most common research methods are:

• blood test for RW (RW) - Wasserman analysis;
• RPHA – passive hemagglutination reaction;
• ELISA – enzyme immunoassay of blood;
• RIF – immunofluorescence reaction;
• RPR – microprecipitation reaction with cardiolipin antigen;
• RIBT – immobilization reaction of Treponema pallidum.

What is the Wasserman reaction

This is a laboratory blood test for syphilis, which is aimed at determining the immunological reaction to the penetration of the pathogen into the body. Characteristic processes begin in the human body during infection. The causative agent of the disease contains the antigen cardiolipin. The patient's blood serum, due to the presence of reagins in it, enters into a complement fixation reaction. The result is a specific complex with this antigen, which RV can detect.

When infected with syphilis, a person will definitely have antibodies to Treponema pallidum in his blood, which is characterized as a physiological response of the immune system. During the test, the drug cardiolipin is added to the collected blood. If the causative agent of syphilis is already in the body, the result will be visible RSC, which binds the introduced antigen and antibodies. In the decoding, the number of “+” signs indicates the intensity of the formation of complexes or “-” in their absence.

Indications for the study

It is recommended to regularly conduct a general blood test in order to promptly identify any abnormalities in the human body; staging the reaction at an early stage can significantly increase the effectiveness of treatment. The following indications exist for donating serum to RW:

1. During professional examinations and medical examinations on a regular basis for employees of trade, medicine, and education.
2. During pregnancy. There is a possibility of infection of the fetus with syphilis in the womb, so it is important to identify the result of the Wasserman test in women who are planning to give birth to a child or are already carrying one. Pathology can cause serious harm to the baby.
3. People who have had long-term contact with pathology at work or at home.
4. If a person suffers from alcoholism or drug addiction.
5. During urgent hospitalization of a patient with signs of syphilis.
6. After intimacy without using a contraceptive with a random person.
7. Anyone wishing to become a blood or sperm donor must be tested.
8. If the pregnancy was terminated unnaturally.
9. The test is carried out during and after serving time in prison.
10. The reason for performing RV is the hospitalization of a patient with enlarged nodes of the lymphatic system and elevated temperature.

Blood for the Wasserman reaction during pregnancy

This is the initial test that your OB/GYN will ask you to take. A blood test for the Wasserman reaction may be inaccurate because the woman’s condition during this period affects the results. According to statistics, 32% of cases show a false positive result. If there is a “+” in the decoding, it is necessary to undergo differential diagnosis. It is recommended to perform the test once per trimester, regardless of the presence or absence of sexual intercourse. There are no contraindications for RW for pregnant women; this is a standard collection of material.

Preparation

Some tests require specific preparation before taking. Wasserman's analysis will be as reliable as possible if 2 days before the test you do not drink any alcoholic beverages (even low-alcohol ones). It is recommended not to eat fatty foods during this period, so as not to distort the results. You should not take any digitalis preparations while preparing for RV.

How is the procedure performed?

Blood for the Wasserman reaction is carried out only on an empty stomach, this is an important condition. The last meal before collection should be no later than 6 hours. The employee who performs the manipulations sits the client on a chair or places him on a couch. The analysis requires 8-10 ml of blood from the cubital vein. If the study is carried out on a small child, then the material can be taken from the jugular or cranial vein.

How many days does a blood test for RW take?

There are two stages in conducting material research. Wasserman's rapid test will be ready in 2 hours, but it can only confirm or refute the presence of syphilis antibodies in the patient. To obtain quantitative information on the state of the blood and the concentration of antibodies to treponema, it takes from 1 to 7 days. The duration of analysis and interpretation depends on the laboratory and the number of ongoing tests.

Decoding

A blood test according to Wasserman should only be deciphered by a qualified doctor. The results may indicate not only a negative or positive reaction, but also something in between. Only a specialist will be able to correctly interpret the data and not frighten the patient ahead of time. A typical negative result is indicated by a “-” sign and indicates the undoubted absence of syphilis in the human body.

Positive reaction

When assessing the concentration of antibodies, a positive manifestation may be marked by one, two, three or four pluses. The following symbols may appear in the decoding:

1. “+” and “++” - the result indicates a dubious, weakly positive microreaction. Additional diagnostic tests and examination are necessary. After some time, you can repeat the analysis of August Wasserman, because there is no complete confidence in the absence or presence of syphilis. The reason for this result may be a violation of the preparatory procedures before donating blood.
2. “+++” is a positive reaction. No additional or repeated confirmation is required; the patient has syphilis and must undergo a full examination. Women are prescribed a smear from the vagina or uterus, men donate material from the urethra. This result is rarely erroneous, but clarifying tests may be prescribed if the patient’s symptoms are similar to other diseases.
3. “++++” is the final positive result. High reaction intensity.
4. “++++” is the final positive reaction. The result obtained is 100% reliable and does not require any additional analysis. The diagnosis is syphilis.

False-positive Wasserman reaction

An absolutely healthy person can receive such an answer; this happens for specific reasons. This reaction occurs if the patient has acute or chronic stages of the disease, has recently received vaccinations, or has recently suffered physical injury. All these conditions lead to the active production of a nonspecific protein in the body, which is called antibodies or immunoglobulin. The RW analysis is aimed at identifying these proteins and recognizing them as syphilitic. This becomes the basis for obtaining a false positive result.

Causes

It was described above why a patient may receive a false positive result when testing for syphilis. Here is a list of conditions that can lead to this:

• myocardial infarction;
• alcohol, food poisoning;
• acute, chronic liver pathologies, hepatitis D, C, B;
• soft tissue or bone injuries;
• age-related changes in the functioning of the patient’s body;
• tuberculosis;
• autoimmune diseases.

Video

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