home→Diseases→ If the analysis of r sharply positive that. What does a positive Wasserman reaction indicate and what to do with this result

If the analysis of r sharply positive that. What does a positive Wasserman reaction indicate and what to do with this result

When passing mandatory medical examinations, an RW blood test is performed - what is it, the doctor will tell. The abbreviation stands for Wasserman reaction. This study is a method for diagnosing syphilis, helps to identify the presence of even a latent form of the disease. Such an analysis should be taken on an empty stomach and following certain rules.

What is an RW blood test

A special category of medical research includes blood for RW, or the Wasserman reaction. This technique detects markers of syphilis in the blood and determines how much time has passed since the moment of infection (after contact with the carrier of the infection). Today, donating blood for RW is the only way to diagnose a latent form of the disease. The reliability of the analysis affects the therapy program, the result of which depends on the quality of life of the patient.

Syphilis is a chronic sexually transmitted disease that causes the causative agent of pale treponema. It is characterized by the manifestation of ulcers on the skin, mucous membranes. With timely diagnosis, syphilis is successfully treated with immunomodulatory drugs. An analysis for RW determines the causative agent of syphilis and specific antibodies to it produced by the human immune system.

Indications for analysis

It is mandatory for medical workers, employees of cosmetology and dermatology offices, and food workers to donate blood for RV. Other indications for a specific test are:

pregnancy planning;
preparation for operations;
unprotected sex (especially with a new partner);
suspected sexually transmitted infections;
blood or sperm donation;
the appearance of an incomprehensible rash on the mucous membranes and skin, discharge from the genitals, failure menstrual cycle among women;
visible (especially in the groin).

Training

Before analysis, any medications. Coffee, tea, alcohol and juices must not be drunk at least 12 hours in advance, only water is allowed. If you need to take a life-saving drug, alert the laboratory assistant. Antibiotics should be discontinued a week before the test. The day before the study, it is better to exclude fatty, smoked, pickled, flour and spicy foods.

How to take a blood test for RW

A blood test for RV is taken on an empty stomach - at least six hours must pass between the meal and the laboratory test. Analyzes in an adult are taken from the cubital vein, in an infant - from the cranial or jugular vein. The patient is seated on a chair or laid on a couch, a vein is pierced and 8-10 ml of blood is taken, sending it for examination. After taking the material, proper nutrition is recommended, a large amount of liquid (it is better to prefer hot sweet tea). On this day, it is better to give up physical activity and alcohol.

How much is being prepared

There are several methods of analysis. The time it takes for the results to be ready depends on which one is chosen. Polymerase chain reaction is the most accurate, new and expensive research method. The result after it is ready in five hours, and the reliability is almost 100%. A serological test is prepared in 1-4 days, when donating blood in district clinics, the tests are ready in 1-2 weeks.

Decryption

Pluses or minuses are put in the form of results. The latter speak of a negative reaction and the absence of illness. A positive reaction can be described by signs from one to four plus signs. The decoding shows the stage of the disease:

++++ or +++ - positive test;
++ – weakly positive;
+ - doubtful, requires rechecking.

If the RW analysis showed a negative, this does not exclude that the person has syphilis in the first or third stage. Plus, a negative reaction may indicate the destruction of red blood cells. The secondary period of syphilis does not always show a positive result. In the first 17 days, the reaction can be negative, and only by the sixth week it can show ++++, and even then only in 25% of patients with syphilis. After that, the reliability approaches 80%. Approximately 5% of healthy people show a false positive result.

RV analysis is positive

If the obtained analysis for RV is positive, this indicates the presence of antibodies to pale treponemas in the blood - that is, about 1.5 months have passed since the moment of infection. Other reasons for the appearance of ++++ in the results sheet are:

carrying out antisyphilitic therapeutic measures - reducing the acute process;
pregnancy in the absence of the disease itself - the decoding of the analysis will be weakly positive in about 1.5% of women;
primary syphilis - 80% of cases at 6-8 weeks;
secondary syphilis in 100% of cases;
clinical recurrence of the disease;
the tertiary period of the disease - in 75% of cases;
early congenital syphilis.

RW negative

When you receive a negative test result, you can talk about the absence of infection and antibodies to syphilis in the body, but this is not always the case. In the early stages of the disease, the results will be negative, because the antibodies simply do not have time to develop. Plus, certain diseases and individual characteristics of patients affect the failure of reliability.

False positive reaction

In 5% of patients, false positive reaction- a state when the analysis shows ++, but the patient is not sick. The reasons for false positive manifestations are:

tuberculosis, systemic red, leprosy, leptospirosis, cancer, typhoid, scarlet fever, HIV and;
beriberi and sleeping disease, hepatitis;
in pregnant women or those who have just given birth;
during menstruation;
after anesthesia, alcohol, drugs, fatty foods, coffee, cigarettes, drugs, administration of certain serums or vaccinations;
acute infections pregnant.

What to do if RW is positive

If the obtained data show ++++ or ++, a secondary blood sampling is also necessary. Sometimes ORS (selective reaction to the disease) is used. To do this, blood serum is applied to a glass slide, cardiolipid antigen is added. If the repeated result is positive, a visit to a venereologist is required to make an accurate diagnosis.

To prevent congenital syphilis in children, pregnant women donate blood for RW for all nine months: this analysis is one of the mandatory procedures for expectant mothers. If an infection occurs in a pregnant woman, it is necessary complex treatment the first months. If treatment is neglected, the consequences are dangerous for both the mother and the unborn child.

Most screening research methods are associated with various analyzes blood. They are designed for mass examination of people in order to identify dangerous diseases. The technique for performing them (analysis from a vein or a finger) and the price of reagents are so simple and affordable that every state medical institution examines its patients for free. But recently there have been conflicting data regarding the RW blood test. According to them, this study is not always as informative as it was previously thought.

What is this analysis

The essence of the blood test for RW is to determine the specific markers of syphilis. This sexually transmitted disease, like any infectious process, causes the appearance of antibodies that provide an immune response and protect the body from the progression of the disease. The analysis, during which these specific antibodies are determined, is called the Wasserman reaction, or blood for RW.

How is it carried out, and what kind of blood is needed for analysis

The material for analysis can be any blood, both from a vein and from a finger. The specificity and reliability of the analysis performed depends on many factors. It is important to consider that this is a non-specific test that has a large number of false positives and false negatives. Therefore, it cannot be relied upon with complete certainty in any case. This is due to the fact that blood from a finger can only be examined using the microprecipitation reaction.

It allows you to quickly determine the presence of antibodies in the body. But their specificity cannot be determined. Such antibodies can be any proteins that are formed in large quantities during any infectious processes, allergic reactions of an immediate and delayed type. This means that the true disease can masquerade as a false positive RW and be mistaken for syphilis. On the other hand, venous blood from a finger is not able to detect small concentrations of specific antibodies to the causative agent of syphilis in initial stages disease or its sluggish course. This causes a false negative result.

Important to remember! The diagnostic value of a blood test from a finger on RW is so low that it makes this method of conducting it impractical in medical practice. More reliable results can only be obtained by examining venous blood. In contrast to the fingertip test, which makes it possible to examine only a small amount of whole capillary blood, plasma can be obtained from venous blood, which contains all the antibodies circulating in the body!

Do not forget about the correctness of the study. Donating blood is best in the morning, or at least on an empty stomach. On the eve, strong physical and psycho-emotional stress is excluded. It is desirable to minimize the introduction of drugs that affect the activity of the immune response and cause an allergic reaction.

In what cases is it assigned

The expediency in conducting a blood test for RW has two goals.

Diagnostic

It involves examination of persons at risk for the development of syphilis or those who have this disease must be excluded:

If there are complaints characteristic of sexually transmitted diseases, or unprotected casual sex;
In the presence of any manifestations of syphilis;
During pregnancy. All pregnant women are examined for RV when registering with antenatal clinic and again during pregnancy;
All patients who are hospitalized in medical institutions, especially surgical hospitals;
All persons undergoing routine medical examinations;
Medical workers;
Contact with patients with syphilis;
Drug addicts and HIV patients;
Persons with prolonged fever and doubts about the reliability of the diagnosis.

A blood test for RW can detect antibodies to pale treponema, the causative agent of syphilis

Therapeutic purpose

Assumes RW in the dynamics of all patients with syphilis. This allows you to determine the secondary and tertiary forms of syphilis, which are masked under the mask of any disease. internal organs. In patients being treated with established diagnosis syphilis, thanks to RW, the dynamics of the course of the process, its activity and the effectiveness of the applied medications.

How to correctly evaluate the results

Deciphering the results of a blood test for RW can be represented by several options.

RW negative (normal)

It says that no antibodies to the causative agents of syphilis were found in the blood of the subject. This means that he has nothing to do with this disease.

RW positive

There are 4 degrees of positive reaction, which are indicated by the corresponding number of + signs. The more of them, the greater the likelihood of contracting syphilis. All individuals with a positive RW are subject to re-examination. In patients who have recovered from syphilis, a positive RV in the form of 4 pluses can be maintained for life.

RW false positive

May be with:

Active inflammatory process in the lung tissue, including tuberculosis origin;
Systemic diseases connective tissue;
Arthritis of various origins;
After vaccination or infectious diseases;
In pregnant women;
malignant tumors;
Diabetes;
Viral hepatitis and HIV infection.

If there are doubts about the reliability of the results of the blood test for RW, it can be carried out using more modern serological diagnostic methods (take blood from a vein for RIF, ELISA), which have higher specificity and reliability.

Important to remember! A negative RW does not give a 100% guarantee of the absence of syphilis. This is due to the presence during this disease, the so-called seronegative window. This means that from the moment of infection with syphilis, some time must pass for the formation of appropriate antibodies. If blood from a vein, and even more so from a finger, is taken during this time period, a false negative result will be obtained!

The technique for performing them (analysis from a vein or a finger) and the price of reagents are so simple and affordable that every state medical institution examines its patients for free. But recently there have been conflicting data regarding the RW blood test. According to them, this study is not always as informative as it was previously thought.

What is this analysis

How is it carried out, and what kind of blood is needed for analysis

It allows you to quickly determine the presence of antibodies in the body. But their specificity cannot be determined. Such antibodies can be any proteins that are formed in large quantities during any infectious processes, allergic reactions of an immediate and delayed type. This means that the true disease can masquerade as a false positive RW and be mistaken for syphilis. On the other hand, venous blood from a finger is not able to detect small concentrations of specific antibodies to the causative agent of syphilis in the initial stages of the disease or during its sluggish course. This causes a false negative result.

In what cases is it assigned

The expediency in conducting a blood test for RW has two goals.

Diagnostic

It involves examination of persons at risk for the development of syphilis or those who have this disease must be excluded:

If there are complaints characteristic of sexually transmitted diseases, or unprotected casual sex;
In the presence of any manifestations of syphilis;
During pregnancy. All pregnant women are examined for RV when registering at the antenatal clinic and again during pregnancy;
All patients who are hospitalized in medical institutions, especially surgical hospitals;
All persons undergoing routine medical examinations;
Medical workers;
Contact with patients with syphilis;
Drug addicts and HIV patients;
Persons with prolonged fever and doubts about the reliability of the diagnosis.

A blood test for RW can detect antibodies to pale treponema, the causative agent of syphilis

Therapeutic purpose

Assumes RW in the dynamics of all patients with syphilis. This allows you to determine the secondary and tertiary forms of syphilis, which are masked under the guise of any diseases of the internal organs. In patients undergoing treatment with an established diagnosis of syphilis, RW determines the dynamics of the course of the process, its activity and the effectiveness of the medications used.

How to correctly evaluate the results

Deciphering the results of a blood test for RW can be represented by several options.

RW negative (normal)

It says that no antibodies to the causative agents of syphilis were found in the blood of the subject. This means that he has nothing to do with this disease.

RW positive

RW false positive

Active inflammatory process in the lung tissue, including tuberculosis origin;
Systemic connective tissue diseases;
Arthritis of various origins;
After vaccination or infectious diseases;
In pregnant women;
malignant tumors;
Diabetes;
Viral hepatitis and HIV infection.

What does a blood test for RV say?

A blood test for RW (RW) or the Wassermann reaction is a laboratory diagnosis of syphilis. This disease is quite serious, it leads to serious consequences in the absence of timely treatment. At the same time, syphilis in many cases is asymptomatic. At the same time, it is dangerous not only that the disease destroys human organs and systems, but also that the patient himself becomes a source of infection for his sexual partners. Consider what this blood test is, and how to take a blood test for RV.

Blood test for RV

Syphilis is a systemic chronic venereal infectious disease that affects the mucous membranes, skin, bones, internal organs, nervous system. Its causative agent is the bacterium Treponema pallidum. The main route of infection with syphilis is sexual. Most often, infection occurs during unprotected intercourse. The predisposing factor of infection is the presence of microdamages of the mucous membranes and skin. In some cases, it is possible to become infected with syphilis by household means (through linen, hygiene items of a sick person).

Complications of syphilis are more serious the longer a person suffers from this disease. In the primary period, organs are mainly affected genitourinary system. In the secondary period, lesions of the joints and bones of the patient are observed. The tertiary period of the disease is characterized by irreversible damage to the internal organs and systems of the body.

A blood test for RV is a specific category of laboratory tests. It consists in a serological study of blood. With the help of this analysis, syphilis can be detected at different stages of development.

Quite often, a simultaneous blood test for RV and HIV is performed. According to the legislation, mandatory blood tests for RV and HIV are provided for during hospitalization, registration of women during pregnancy, for medical personnel, workers in contact with food, the service sector (cosmetologists, hairdressers). In addition, it is recommended to take a blood test for syphilis after casual sex.

Experts highlight the main advantages of this method of diagnosing syphilis:

analysis makes it possible to detect the disease in its latent forms;
with its help, you can not only confirm primary syphilis, but also determine when the infection occurred;
a blood test allows the doctor to monitor the treatment of the disease.

A blood test for RV indicates the presence of pale treponema in the body, the degree of its activity, the effectiveness of the treatment of syphilis. Also, this study is carried out in the prevention of congenital syphilis in children.

In addition to a preventive study, there are certain indications for prescribing a blood test for syphilis:

casual sex;
the occurrence of a rash on the mucous tissues and skin;
the formation of ulcers on the genitals;
appearance copious discharge from the genitals;
increase lymph nodes;
pain in joints and bones;

Deciphering RV blood tests

The principle of the Wasserman reaction is based on the fact that antibodies appear in the blood of an infected person, which are produced by the immune system. In a laboratory blood test, the cardiolipin antigen is used. With its help, the causative agents of syphilis, pale treponema, are detected.

Deciphering a blood test for RV contains a negative or positive result.

A negative result indicates that there is no infection in the patient's blood. But in some cases, a negative result may be with early primary syphilis or a late tertiary stage of the disease.

A positive test result indicates the presence of antibodies to syphilis in the blood, and hence the disease itself.

Usually, the laboratory issues a form with the results of the analysis. With a positive result, one to four crosses are placed in such a form. What does such a decoding of a blood test for RV mean? The result is decoded as follows:

(+) (+) (+) - the reaction is sharply positive.

If the result of the analysis indicates a doubtful or weakly positive reaction, as a rule, the patient is referred for a second blood test. The fact is that such a reaction does not necessarily indicate a disease with syphilis. The possibility of a false positive result is due to the fact that the cardiolipin antigen can be contained in a small amount in the human body. Usually the immune system does not form antibodies against its own cardiolipin. But sometimes failures occur, and a positive Wasserman reaction appears in a healthy person.

Also, false-positive results of a blood test for RV occur with the following diseases and conditions:

diabetes;
malignant neoplasms;
tuberculosis;
pneumonia;
viral hepatitis;
drug addiction and alcoholism;
transferred malaria, blood and liver diseases;
the period after vaccination;
pregnancy in women.

How to take a blood test for RV

For research, blood is taken from the patient's vein. It is recommended to donate blood in the morning on an empty stomach. At least 12 hours must have passed since the last meal.

On the eve of the blood test for RV, it is necessary to refrain from eating fatty, spicy, salty foods, alcohol-containing drinks. In addition, it is important to limit physical activity.

Smoking should be stopped two hours before blood sampling.

Immediately before blood sampling, you can drink only pure still water.

Why can a RV test be positive?

Fokina Irina Nikolaevna

First, let's figure out what a RV analysis is. A blood test for RW (Wassermann reaction) is a specific category of laboratory tests. It includes a serological study of blood (material is taken from the cubital vein).

A blood test for RW (Wassermann reaction) is of great therapeutic and diagnostic value:

allows you to confirm the diagnosis of primary syphilis and find out the period of infection;

this is the only way to detect syphilis when its forms are hidden;

is the main criterion for evaluating the effectiveness of treatment and its diagnosis of syphilis;

therapy and prevention in the focus of infection (congenital syphilis) and so on are based on the results of this analysis.

Who gets tested for syphilis?

This analysis is assigned to all patients admitted to hospitals or hospitalized. By law, employees of medical institutions, trade and food workers, cosmetologists, etc. are required to undergo this study every month. Even if you are not sure about your partner or you have had casual sex, it is best to play it safe.

The results of the analysis for syphilis.

A positive result of the analysis confirms the number of crosses that are written in the direction:

Doubtful reaction to RW;

Weakly positive reaction to RW;

Positive reaction to RW;

Strongly positive reaction to RW.

A positive reaction to syphilis says that there are antibodies in the patient's blood that respond to infection, and therefore a conclusion is made about the disease. Sometimes a false positive result is possible. This indicator says that cardiolipin is contained in the cells of the human body in a certain amount. The result is negative, it completely excludes the presence of the disease.

Do not be afraid if you find the first two points in the results (positive and weakly positive), for an accurate result you need to repeat the analysis. During pregnancy, with certain types of allergic reactions, with oncological and infectious diseases, with blood diseases, the indicators may be similar to a positive RW result.

Sometimes the data may differ from the first result due to a technical nature - the human factor, because the work in laboratories on the results of a blood test for RW is done by ordinary people, it cannot be automated. Repeated analysis, confirmed the primary, it is urgent to consult a doctor.

Congenital syphilis is a disease that is difficult to treat. Pregnant women donate blood to RW throughout pregnancy to prevent congenital syphilis.

In the case of a positive RV, you need to contact a venereologist, he will conduct additional studies to clarify the diagnosis.

False syphilis:

An analysis for syphilis is one of the most frequent tests that a person has to take throughout his life. All screenings (mass examinations of the population), medical examinations, hospitalizations - everything is accompanied by a blood test for syphilis.

It is not at all surprising that many people experience positive test results without expecting it at all. The majority in such a situation panic rises, the question arises: “Is there an erroneous analysis for syphilis?”. Answer: it happens!

Do not worry in advance - syphilis can be false. To check this, you just need to pass additional tests.

However, even if a positive test for syphilis was not confirmed in the end, the situation itself still remains unpleasant for a person. There are fears: suddenly, nevertheless, there is something ...

To dispel doubts, we will tell you in detail: how, when and under what conditions a test for syphilis can be positive.

False syphilis - why does it happen?

Analyzes can show false syphilis in different human conditions: acute and chronic diseases, injuries, recent vaccinations, etc.

All these conditions are united by the fact that during them non-specific (created to fight various threats) proteins are formed in the blood - immunoglobulins, they are also antibodies.

The Wasserman (RW) test and other tests for syphilis react to these proteins, mistaking them for syphilitic ones, since they are similar. Although in reality the body could create non-specific proteins to protect against a completely different pathogen. As a result, these "harmless" immunoglobulins cause false positive results for syphilis.

When can this be?

For various reasons, tests for syphilis can erroneously become positive. This condition may be short-term or persist for several years. False results can be roughly divided into "acute" and "chronic".

"Acute" false results are due to acute illness or injury and persist for up to 6 months. The reason for their appearance may be:

Acute infectious diseases (usually with high fever);
injury;
myocardial infarction;
vaccination;
poisoning.

"Chronic" false results occur in the context of chronic conditions and may recur for more than 6 months. These states include:

Connective tissue diseases;
tuberculosis, leprosy and other chronic bacterial infections;
chronic viral infections: HIV, hepatitis B, C, D, etc.;
liver disease;
autoimmune diseases;
age-related changes in the body.

Who can be trusted? Let's compare the accuracy of all tests for syphilis!

While syphilis tests are fairly accurate, sometimes they can still be wrong. The purpose of most syphilis tests is to check if a person has antibodies in their blood that their body has made to protect against Treponema pallidum. For such a test, researchers take either the real causative agent of syphilis (pallid treponema), or its artificial counterparts.

The accuracy of the analyzes depends on many technical conditions, but one of the most important is the material that is used for testing. If artificial analogues of pale treponema are taken for analysis (these analyzes are called so: non-treponemal), the result will be less accurate. If you used real treponema (treponemal tests) - the analysis will be much more accurate.

It turns out that among all tests for syphilis, non-treponemal tests are most often mistaken: they give a false positive result more than others. Since they are the cheapest, they are used for mass surveys of the population. But those who have a positive non-treponemal test result are examined with the help of more expensive and accurate treponemal tests.

Non-treponemal screening tests include: RMP, VDRL, USR, RPR, and TRUST. The most accurate of these tests are RPR and TRUST. The probability of their error in positive side is 1–2%. Slightly less accurate - RMP and VDRL. The probability of their error is 2–3%. USR is the least accurate - its error is 7%.

Among treponemal tests (RIF, RPGA, ELISA, immunoblotting), the probability of error is less than 1%.

The most accurate positive results are obtained by direct research methods (a special subspecies of high-precision analyzes): dark-field microscopy (error 0-2%) and PCR (error 0-1%). However, these methods often give a false negative result - that is, they say that there is no disease, when in fact it is. This prevents them from being used as basic tests.

For the most reliable results, one non-treponemal test is performed first, and then, in the case of a positive result, one treponemal test.

Doubtful result - error or not?

When “negative” or “positive” comes in the test results for syphilis, the meaning is unambiguous and understandable. But when there are 1-2 crosses on the form or “doubtful result” is written, the question arises: “What is it, and can this mean a test error?”.

Not necessarily: a questionable result means only a small amount of antibodies in the blood. For example, this could be a sign early syphilis (incubation period and the first weeks of hard chancre), when antibodies only appear, or a sign of late syphilis (after 2-4 years), when antibodies (IgM) gradually disappear.

In this situation, as with a strongly positive test, an additional confirmatory treponemal test is performed.

A negative additional treponemal test result can mean one of two things:

The first test was wrong, and there is no syphilis.
Antibodies have not yet developed, and syphilis is in the incubation/primary period.

In any case, if the results of the screening test are questionable, it is recommended to repeat it after two weeks.

A positive treponemal test result indicates that syphilis is definitely present and the patient needs treatment.

Syphilis found! Who will the doctors tell about it?

When syphilis is confirmed, do not panic. Feel free to contact your local skin care clinic. Neither the authorities, nor colleagues at work, nor relatives will be told about your illness. However, a person must be aware that syphilis is an infectious and highly contagious disease, so his environment, especially his family, is in serious danger.

If the diagnosis of syphilis is confirmed, it is very important to carefully consider the following recommendations:

The dermatovenereologist should show his partner and all family members, since, perhaps, the infection has already occurred through sexual and domestic contact.
If the partner and children do not have syphilis, they should still receive preventive treatment - small doses of penicillin to prevent the development of the disease if the infection has already occurred. Read more about the prevention of syphilis in a separate article.
If a person works, he is issued a sick leave for the duration of treatment, while at work no one is notified about the illness. In all extracts and any other medical documentation, the disease is encrypted, and only doctors have access to this information. A medical book, if any, is issued (or renewed) immediately after the treatment.
Treated syphilis is not dangerous and cannot be the reason for dismissal from work or denial of employment.
If a teenager has become infected, he/she can also apply to the Department of Internal Affairs without fear that parents will be told about the disease. He/she will get a separate card, and examination and treatment in the KVD at the place of residence will be free.
After successful therapy, a person should be issued a document confirming the treatment received. The document must be kept and taken with you to all medical examinations. This will save you from unnecessary questions and attention from doctors, since the tests after the treatment can remain positive for a long time.

False positive syphilis in pregnancy

Is there false syphilis in pregnant women? Of course it does. In practice, this is not a rare situation.

Women donate blood for syphilis several times during pregnancy: in the first 12 weeks, a few weeks before childbirth (30-35 weeks) and immediately before childbirth (38-40 weeks) - this is the necessary minimum of tests.

It is not at all surprising that with a positive RW analysis during pregnancy, the question immediately arises in women: “Where does syphilis come from?”. But you should not worry in this situation: if your partner has not changed over the past six months or a year, and you are confident in your and his health, then the analysis is most likely erroneous.

Pregnancy is a complete restructuring of the body, both at the hormonal level and at the level of immunity. From the first days, the mother's body tries to protect the child from any threat and therefore produces many different antibodies.

Almost all non-treponemal tests for syphilis respond to these antibodies.

Therefore, if a non-treponemal analysis for syphilis (RW or RMP / MP / RPR) showed that the woman has the disease, then expectant mother additionally, treponemal ELISA or RPHA tests are prescribed - these tests are more reliable and will be able to show whether a person is definitely sick.

Read about the dangers of the disease to a newborn baby in the article “Congenital syphilis”.

RW blood test - what kind of analysis it is, how to take it, the time of the study and the interpretation of the results

What is an RW blood test

Indications for analysis

It is mandatory for medical workers, employees of cosmetology and dermatology offices, and food workers to donate blood for RV. Other indications for a specific test are:

pregnancy planning;
preparation for operations;
unprotected sex (especially with a new partner);
suspected sexually transmitted infections;
blood or sperm donation;
the appearance of an incomprehensible rash on the mucous membranes and skin, discharge from the genitals, failure of the menstrual cycle in women;
visible enlargement of the lymph nodes (especially in the groin).

Training

Before the analysis, any drugs are prohibited for use. Coffee, tea, alcohol and juices must not be drunk at least 12 hours in advance, only water is allowed. If you need to take a life-saving drug, alert the laboratory assistant. Antibiotics should be discontinued a week before the test. The day before the study, it is better to exclude fatty, smoked, pickled, flour and spicy foods.

How to take a blood test for RW

How much is being prepared

Decryption

++++ or +++ - positive test;
++ – weakly positive;
+ - doubtful, requires rechecking.

Blood test for Rw - what is it and the reasons for the analysis

For the initial examination of clinically asymptomatic people and to determine their possible diseases, Rw-based testing is done. And in the outpatient map in the clinic, everyone can see the direction to Rw. It is done not only by sick people, but by some healthy people.

Rw is considered an important test, which, according to the standards of surveys, for the purpose of prevention, is carried out by everyone. The technique is simple and inexpensive, and therefore accessible to the masses, but its effectiveness has recently been called into question. So what is the importance of the analysis, what categories of people fall under the survey and what information does it carry?

Syphilis is an insidious infection that makes itself felt already at a late stage. Today, this is a common disease, and the main reason for this is the ignorance of young people and their ignorance of how to behave in the event of personal infection or infection of a loved one.

Wasserman reaction and blood for RV - what is it

The great German immunologist, who studied problems in the field of infectious diseases, Professor von Wassermann developed a special test, with the help of which syphilis infection is determined by blood. The Wasserman reaction (rapid diagnosis of syphilis, or Rw for short) has been a mandatory analysis for more than a century, which has been introduced into the standards of professional examinations. The essence of Rw is manifested in the definition of syphilis in a person.

This venereal infectious disease is dangerous due to its asymptomatic early stage a person can live without knowing about it, while infecting other people.

The study shows how during infection, specific antibodies appear that try to protect the body from the spread of the disease. These antibodies, which provide an immune response, determine the presence of syphilis markers. This antibody reaction was called the Wassermann reaction.

The main problem in determining the infection is a long latent period at the beginning of infection of the body. Later, in infected people, paired complexes appear in the blood, which attract infectious agents and their elements and prevent the destruction of red blood cells. A healthy person does not have such complexes.

According to the severity of hemolysis, 4 stages of infection are determined (indicated by +). An interesting fact is that people who have recovered from syphilis have an indicator of four plus for the rest of their lives.

Where is blood taken for analysis and under what conditions is Rw performed?

To conduct a study and obtain information about the infection, 10 ml of any blood is enough - from a vein or a finger. But this is a non-specific analysis, and it has many additional factors that affect the result. So, the test can show, in addition to positive and negative results, also Rw false positive and Rw false negative.

Biological material is usually taken in the morning, but it can also be taken at other times, the main thing is on an empty stomach or six hours after eating. Before donation, it is better not to use drugs that affect the immune system and lead to allergic reactions, engage in physical activity. One hour before the delivery of the RV, you can not smoke, and at least a week - stop using antibiotics.

It is also better not to take Rv if there was a strong shock or a big emotional load the day before.

How is a blood test for the Wasserman reaction performed?

If red blood cells are destroyed in the blood serum, it is believed that the person is healthy. If not, it means that treponema pallidum bacteria are present. Based on the results, the duration and stage of infection are determined.

But there is a difficulty here: if RW is made in the first 17 days from the moment of infection, the analysis may show a false negative result. At a period of 5-6 weeks after infection, in 20 cases out of 100, infection can be determined, and from 8 weeks - in 80 cases out of 100. In addition, in 5 cases out of 100, the RW test is false positive, and therefore, with a positive result, a second test for R is carried out. w, which will either confirm the result or refute it.

RW false positive arises from the fact that the presence of antibodies is easily determined, but their specificity is much more difficult to disassemble. After all, the infection can be caused by another ailment or allergy that masquerades as syphilis. In the same way, a false-negative RW result is shown in the analysis at the first stage of the disease or during its sluggish passage, when low concentrations do not allow the text to be carried out.

This is especially true for blood from a finger. Therefore, it is more appropriate to conduct an analysis based on studies of venous blood.

The Wasserman reaction (Rw) makes it possible:

Make a diagnosis of syphilis at the primary stage;
Designate the timing of infection;
Determine the presence of infection in the latent course of the disease;
Identify patients who have already recovered;
Conduct a survey of all people who were close to the patient;
Forensic experts to get more information on the criminal case.

When conducting laboratory studies, an error of up to 10% is allowed, and other methods of analysis are offered that have high specificity and reliability of the results, such as:

enzyme immunoassay (ELISA);
Serological analysis (MR);
RPGA;
Pale treponema immobilization reaction (RIBT);
Immunofluorescence reaction (RIF);
Immunoblotting.

Reasons for having a blood test for Rw

The reaction is carried out in two cases.

For examination and diagnosis. To avoid the spread of infection, to identify infected people, as well as for preventive purposes, it is strongly recommended to donate blood:

People who are associated with the cultivation, sale and processing of food (sellers, cooks in public catering, schools, kindergartens, workers in factories, farms, etc.);
Health workers (all personnel of medical institutions);
People who come into contact with those infected with this infection;
Dependent people, drug addicts and HIV-infected;
Donors (blood, sperm, etc.);
People who applied for the first time medical care or admitted to a hospital
Patients on the eve of surgery;
People with prolonged unidentified symptoms accompanied by fever;
People who are going to go to sanatorium bases and health resorts;
pregnant several times;
With pain in the bones;
Everyone with signs of syphilis (enlarged lymph nodes, ulcers on the genitals, skin rash, etc.);
Anyone undergoing an annual scheduled medical examination.

In the process of treatment. It is prescribed to determine the dynamics of the course of the disease and forms of syphilis (secondary, tertiary), which often manifest themselves as diseases of the internal organs. It also turns out the effectiveness of the treatment, how well the drugs work, if necessary, the treatment is adjusted.

How to take an Rw test for pregnant women?

Rw, like any other test, has its own term, for different organizations it ranges from 20 days to 3 months.

Therefore, pregnant women are prescribed a study on RV at least three times:

When registering for pregnancy;
At the thirtieth week of the duration of pregnancy;
During admission to the maternity ward.

For pregnant women who have had syphilis, you can plan to conceive a child no earlier than 5 years later. Moreover, Rw of pregnant women in 1.5 cases out of 100 shows a false positive result of infection. A re-diagnosis is scheduled and the result is refuted.

But if there really is an infection, then the pregnant woman is prescribed treatment, which is aimed at preventing intrauterine infection of the fetus, its birth with an infection, or the death of an unborn child.

Signs of syphilis

Rw from the beginning of the 20th century is still used according to the classical method. Diagnosing syphilis in the laboratory makes it possible to determine which of the people has become infected, but the analysis itself is technically difficult, and therefore it can neither be automated nor used for mass diagnostics. RW analysis is low specific.

Outwardly, syphilis manifests itself for a very long time, especially in those people who have a strong immune system. For example, in the first stage, the chancre is localized in men on the penis, and in women in the vagina, and therefore if sexual intercourse is protected by a condom, then the infection will not be transmitted. If the second stage has come, then the lesions will be all over the body and in the mouth.

The special features are:

Ulcers of venereal origin on the male and female genital organs and near the anus;
Hard chancre;
Rash all over the body and on the oral mucosa.

After accidental unprotected intercourse;
If an infected person lives near you;
If you are planning to conceive a child;
If you feel pain in the bones.

Evaluation of results Rw

RW positive - if the antigen of pale treponema cardiolipin was detected in the blood serum, this means that the result is positive for syphilis. There are 4 stages of a positive reaction. The more of them, the greater the likelihood of human infection. A re-analysis is scheduled for additional research.
RW is negative - it means that the blood is normal and the person is healthy;
RW false positive - this is possible with other diseases that masquerade as syphilis:

Tuberculous inflammatory processes in the lung tissues;
Diseases in the connective tissues;
After infectious diseases and after vaccination;
In the presence of a tumor;
With diabetes;
With hepatitis and HIV infection;
Within ten days of the child from birth;
During menstruation;
With alcoholism or taking fatty foods;
With rheumatoid diseases;
With brucellosis;
In case of poisoning;
With cirrhosis of the liver;
With a stroke;
During pregnancy.

RW false negative - such an assessment is possible during the seronegative window. After infection, a long period passes before antibodies are formed in the blood, and as long as their number is very small, then the result will seem negative. The result may also be incorrect if you take blood from a finger - syphilis is very difficult to detect, its significance in diagnosis is very low and, most often, in the early stages it will not show a real picture of what is happening.

The director of the Institute for Experimental Therapy in Berlin, Professor Wassermann, made a great discovery. And although RW is now obsolete and very rarely performed (due to its non-specificity in many cases), since it has been replaced by the microprecipitation reaction, this discovery gave immunologists a good impetus for the development of analysis of infections. For example, ELISA and RIF indicate infection with syphilis with high accuracy.

But still, this infection exists and affects people. And this means that the topic has not lost its relevance.

Blood test for syphilis (RW)

Blood tests

general description

The Wassermann test (RW) is the most popular immunological test used to diagnose syphilis since its discovery in 1906. RW belongs to the group of complement fixation reactions (RCC) and is based on the ability of the blood serum of a patient with syphilis to form a complex with the corresponding antigens. Modern RSK methods used to diagnose syphilis differ significantly in their antigens from the classical Wasserman reaction, however, the term "Wasserman reaction" is traditionally retained for them.

Diseases and cases in which the doctor may prescribe a blood test for RW

Syphilis.
Suspicion of syphilis in people who are in contact with patients with syphilis.
Pregnancy.
Drug addiction.
Abortion.
Fever, accompanied by an increase in regional lymph nodes.
Initial visit to the clinic.
Admission to hospital for treatment.
Treatment in a psychiatric or neurological hospital.
Donation of blood, tissues, sperm, other body secrets.
Work in the service sector, trade, medical care, social and educational areas.

Carrying out the procedure for taking a blood test for RW

Blood on RW is given only on an empty stomach. The last meal should be no later than 6 hours before the test. The medical worker seats the patient or lays him down on the couch and takes 8-10 ml of blood from the cubital vein.

Preparing for a blood test for RW

For 1-2 days before the test, you should stop drinking alcohol. It is also not recommended to eat fatty foods - it can distort the result. During the preparation for the analysis, you should refrain from taking digitalis preparations.

Contraindications

The result of the analysis will be false if:

the patient has an elevated body temperature,
a person is sick with an infectious disease or has just recovered from it,
a woman is menstruating,
pregnant in the last weeks before childbirth,
the first 10 days after childbirth,
the first 10 days of a baby's life.

Deciphering the results of the analysis

In primary syphilis, the Wasserman reaction becomes positive at 6-8 weeks of the course of the disease (in 90% of cases), while the following dynamics are noted:

in the first days after infection, the reaction in most patients is usually negative;
on the 5th-6th week of the disease, in about 1/4 of the patients, the reaction becomes positive;
at 7-8 weeks of illness, RW becomes positive in most.

With secondary syphilis, RW is always positive. Together with other serological reactions (RPHA, ELISA, RIF), it allows not only to identify the presence of the pathogen, but also to find out the approximate time of infection.

With the development of a syphilitic infection on the 4th week of the disease, after the onset of primary syphiloma, the Wasserman reaction changes from negative to positive, remaining so in the secondary fresh and in the secondary recurrent period of syphilis. In the latent secondary period and without treatment, RW can turn negative so that when a clinical relapse of syphilis occurs, it becomes positive again. Therefore, in the latent period of syphilis, a negative Wasserman reaction does not indicate its absence or cure, but only serves as a favorable prognostic symptom.

Recovery after passing the analysis

After taking a blood test, doctors recommend a proper and balanced diet, as well as as much liquid as possible. You can afford warm tea and chocolate. It will be useful to refrain from physical activity and in no case take alcohol.

Norms

Normally, hemolysis should be observed in the blood - this is considered a negative reaction to syphilis (Wassermann reaction is negative). If there is no hemolysis, the degree of reaction is assessed, which depends on the stage of the disease (marked with “+” signs). In this case, you should be aware that in 3-5% of perfectly healthy people, the reaction may be false positive. At the same time, in the first days after infection, the reaction in sick people can be false negative.

Why do I need a blood test for RW and what it can show

RW blood test - what is it and why is it prescribed? The study is carried out with a preventive or diagnostic purpose to detect antibodies to pale treponema, the causative agent of syphilis. Timely detection and treatment of a dangerous sexually transmitted disease will help maintain the health of the patient and reduce the risk of infecting others.

What is R.W.

Syphilis is a sexually transmitted disease and is most often transmitted sexually, but infection can also occur through household contact with the patient.

The insidiousness of the disease lies in the fact that the first signs of infection do not appear immediately and often a person, unaware of his disease, serves as a source of infection for others. A timely test for syphilis makes it possible to detect the disease in a timely manner and prevent the risk of infecting others.

Most people who get a blood referral to RW will say they don't have syphilis and don't need it. But is there any reason to be outraged? The study is very simple and does not take much time, and an extra confirmation that no antibodies to pale treponema were found will only serve as confirmation of health.

What is the study based on?

A blood test for the Wasserman reaction (RW) is based on the fact that when Cardiolipin is added to the blood of an infected person, an agglutination reaction occurs. The intensity of the reaction is estimated with a “+” sign and a positive indicator can range from one to 4 pluses.

The research is carried out as follows:

a small amount of material is taken from the patient from a finger or from a vein;
add Cardiolipin to the blood;
evaluate the speed and intensity of the resulting agglutination.

Laboratory diagnostics is carried out quickly: in emergency laboratories, the result can be obtained within an hour.

The low cost and availability of diagnostics makes it possible to detect syphilitic lesions in a timely manner and reduce the risk of infection spreading.

A certificate stating that the Wasserman reaction is negative in the blood test is required when traveling to a sanatorium, when applying for a job, and in all other cases when contact with people is necessary.

The value of laboratory diagnostics

Knowing what the Wasserman reaction is, it becomes clear the importance of laboratory diagnostics. Analysis allows you to:

identify infection with pale treponema at an early stage;
determine the stage of the course of syphilis;
conduct a differential diagnosis (with neurosyphilis or a visceral form of the lesion, there are no signs characteristic of the disease);
check the effectiveness of the therapy;
remove recovered from dispensary registration;
identify those infected after contact with an infected person.

RW analysis is of great importance in modern medicine. It allows you to timely detect and prevent the further spread of syphilis. This type of diagnosis should not be neglected, especially since during a medical examination or examination, the biomaterial is taken for several analyzes at once. Separately, the Wassermann reaction is prescribed only when characteristics disease or to control the quality of treatment.

Indications for examination

Donating blood for syphilis is a standard diagnostic procedure. Its purpose is shown in the following cases:

Prevention

A blood test for RW is routinely shown to the following groups of people:

health workers;
people working in the food or service industry;
donors;
patients with planned hospitalization in a hospital;
prisoners in places of detention;
persons going to sanatorium-and-spa treatment;
patients undergoing a planned medical examination;
pregnant women upon registration;
people after intercourse with a random sexual partner;
HIV infected;
intravenous drug addicts;
people from the environment of the patient;
persons who first applied to the clinic for medical help.

In all the above cases, the purpose of the examination is to exclude possible human infection.

Clarification of the diagnosis

Syphilitic lesions do not always proceed with characteristic symptoms, in immunocompromised patients or those taking antibiotics for a long time, the disease may manifest in atypical form masquerading as other diseases. For syphilis analysis to conduct differential diagnosis should be done in the following cases:

hyperthermia of unknown etiology;
prolonged pain in muscles and bones;
discharge from the genitals;
skin rash that is difficult to treat;
enlarged lymph nodes;
the appearance of ulcers;
the presence of other sexually transmitted diseases;
signs similar to those of syphilis;
disease control.

A blood test for RV helps to refute infection with pale treponema or confirm the diagnosis and choose the appropriate treatment tactics.

Data decryption

A blood test for syphilis can be:

Negative - "-". A person is either healthy, or less than 5 weeks have passed since the infection entered the body.
Weakly positive - one "+". It can be observed during pregnancy, tuberculosis, oncology, chronic hepatitis and some other non-syphilitic processes.
Positive - "+". Almost always, this is a sign of the presence of treponema pallidum in the body.

Depending on the number of pluses, the stage of the syphilitic process is determined:

4 - initial, there is an active production of antibodies to the pathogen;
2 - 3 - the second degree, which is characterized by a decrease in the symptoms that have arisen;
1 - 2 - neurosyphilis and other lesions of internal organs.

Venereologists note that when infection is confirmed, a decrease in the number of pluses worsens the prognosis of the disease. A decrease in the strength of the immune response indicates an advanced stage of the disease or a weakness in the immune system.

Disadvantages of the Wasserman method

Despite the prevalence of the technique, RW analysis has one big drawback: a positive reaction with Cardiolipin gives not only pale treponema, but also some other pathogens. A false positive result occurs under the following conditions:

pregnancy;
oncological processes;
hepatitis;
diabetes;
infectious diseases (chicken pox, pneumonia, some intestinal infections);
alcohol abuse;
drug use;
blood diseases;
low-quality reagents;
year after remission of syphilis.

Although the PB blood test can be false positive, this technique is very popular due to its simplicity, versatility and availability. Despite the shortcomings, blood for syphilis using the Wasserman method allows you to identify the disease at an early stage.

If a positive result

What to do if the blood for syphilis is positive? First of all, remember a few simple rules:

Do not panic. Based on only one result, the diagnosis is not made, a 3-fold blood test is performed. If all 3 results are positive, then the patient is referred for a consultation with a venereologist.
Visiting a skin care clinic is not scary. You should not take sending for a consultation with a venereologist as a sentence. Before making a diagnosis of syphilis, doctors will run a series of specific tests to look for treponema pallidum. To obtain the most reliable result, you should follow medical recommendations when preparing for testing.
Confirmation of the diagnosis is not scary. When the Wasserman reaction showed that there is a pale treponema in the body, and other methods confirmed this, then you should not despair: the treatment is carried out in conditions of anonymity and in the early stages recovery occurs in almost 100% of cases.

Syphilis is dangerous and can cause serious health complications, but the infection can be successfully cured in the early stages. Timely treatment is possible even during pregnancy: when taking appropriate medications, a woman can endure and give birth to a healthy child.

To donate or not to donate blood for syphilis? The answer is unambiguous - give up. In all public clinics, the Wasserman reaction is done free of charge, and the result is ready within a day. Even if it is positive, then this is not a sentence - syphilis is curable in the early stages.

Syphilis is a serious disease high degree contagiousness. To detect the disease, blood tests (venous and capillary) are used, and in some cases, cerebrospinal fluid is also examined. Deciphering the analysis for syphilis is carried out by the attending physician. The patient can independently see and understand some of the designations in the analysis, but the final conclusion about the presence or absence of the disease should be made by a qualified doctor. A false positive or false negative test for syphilis is possible.

When to see a doctor

For a long time, syphilis was a dangerous disease that could not be cured. modern medicine has all the means to completely cure the disease. The sooner the disease is diagnosed and detected, the easier it will be to treat. Infection with syphilis occurs not only through sexual contact, but also when using the same household items with the patient (toothbrush, towel, kitchen utensils, etc.). Therefore, a periodic rapid blood test for syphilis is recommended for each person.

When infected, there is an increase in the lymph nodes in the groin, the appearance of sores and skin rashes in the mouth and genitals. If the first symptoms of the disease are detected, you should immediately consult a doctor. The examination can be anonymous with a referral from a gynecologist, urologist, proctologist, venereologist or general practitioner. After passing the test, you should contact your doctor for a transcript of the analysis for syphilis.

Purpose of the survey

Often during physical examinations, the doctor may prescribe many laboratory tests, including a test for syphilis. Such a direction should not be taken as a suspicion of a disease. In many areas of public life, a certificate of absence of the disease is required.

Family planning
Registration in the hostel
Admission to the workplace for health workers, catering employees, etc.
Organ or blood donation
Sexually active patients
Availability clinical symptoms
End of syphilis treatment

As a primary study, as a rule, one of the non-specific (non-treponemal) tests is prescribed. The reliability of such tests is relatively low and the patient may get a false positive result. In this case, a second study will be scheduled using a specific (treponemal) test. A positive or negative test should be considered by the attending physician.

Test preparation

Before donating blood from a finger or vein for a laboratory test, you must follow some rules so that the analysis is as reliable as possible. No food, tea or coffee should be consumed 8-12 hours before blood sampling. During the day before visiting the laboratory, it is not recommended to eat spicy, fatty, fried, salty or smoked foods. Antibiotics and other medications can also skew the test. All substances taken should be reported to the attending physician. He may recommend that you refrain from taking the test for 1 or more weeks. A blood sample can be taken at a private laboratory, a district clinic, or a health worker can be called to your home.

In any case, sterile equipment and disposable gloves are used.

Express analysis for syphilis can be done independently at home. Pharmacies offer special tests with detailed instructions in Russian. The test result is known within 10 minutes. One red line on the indicator is negative for syphilis, two lines are positive. The reliability of such tests is not high enough and cannot serve as a confirmation of the diagnosis.

How to understand the result of a non-specific examination

Patients often feel insecure after the test. To donate blood and not be able to decipher the tests for syphilis on your own, of course, is unpleasant. Deciphering a blood test requires medical education and the appropriate qualifications of a doctor, as well as taking into account all the factors that affect the result. Can the patient independently read the results of his syphilis test? Having seen the laboratory report, one can draw simple conclusions, but the doctor must confirm or refute the diagnosis.

A test with toluidine red is prescribed not for diagnosis, but to test the effectiveness of the treatment of the disease. the study shows how much the amount of antibodies has changed compared to the previous analysis. If the figure has decreased, then the treatment is successful. The analysis is carried out in the course of treatment several times as prescribed by the doctor. 3 months after the completion of the procedures, control testing is carried out.

Non-treponemal tests (RSKk, RMP and RPR) are often prescribed during medical examinations and as an express diagnostic. There are several options for designations as a result of research. Deciphering them is quite simple:

"-" negative result
"+", "1+") or "++", "2+" weakly positive analysis
"+++", "3+" or "++++", "4+" positive test for syphilis

Any of the results could be a false positive or false negative for syphilis. In the absence of clinical symptoms and casual sexual contacts, a negative result can be accepted by the doctor as true. A positive reaction is usually checked with a treponemal test.

Results of a specific study

Treponemal tests are complex and expensive compared to non-treponemal tests. There are several types of tests used to diagnose syphilis: RSKt, RIBT, RIF, RPHA, ELISA and immunoblotting). One of the exact specific studies is RIBT analysis. The test result can be presented by the laboratory as a percentage.

20% corresponds to a negative result ("-")
21-30% doubtful analysis ("++" or "2+")
31-50% weakly positive ("+++", "3+")
51% or more corresponds to a positive result

Immunoblotting is one of the modern and accurate methods for diagnosing a disease. Usually appointed in order to confirm or refute the results of the first study. Detection in the blood of antibodies such as IgG and IgM is marked by stripes. The test results are interpreted in comparison with the non-treponemal test.

If both results are negative, the patient is healthy or the infection is in the first week of development. Both positive results indicate the presence of syphilis or another possibly autoimmune disease.

A positive immunoblot test after a negative non-treponemal test indicates the presence of syphilis, an autoimmune disease, or cancer.

There may be a positive reaction in pregnant women. A negative immunoblot test after a positive non-treponemal test indicates no disease.

Reliability of analyzes

There is always the possibility that the test result is wrong. When decoding tests for syphilis, special attention should be paid to external factors that are not dependent on the patient. The laboratory assistant conducting the research or the patient can also be mistaken when he did not properly prepare for blood sampling or did not provide the doctor with truthful information about himself. A false positive result is possible under the influence of the following factors:

Diabetes of any type
The presence of drugs in the blood
Alcohol intoxication
Infectious diseases (measles, hepatitis, mononucleosis, etc.)
Benign or malignant neoplasms
Heart diseases
Taking antibiotics or a recent vaccination
Autoimmune diseases (lupus erythematosus, rheumatoid arthritis etc.)
Pregnancy
Eating fatty, spicy or salty foods during the day before blood sampling

Depending on the stage of the disease, some tests may not detect the disease. So, the Wasserman reaction (RSKt, and RSKk) is carried out only 3-4 weeks after a possible infection with a probability of 100%, in the presence of tertiary syphilis, the reliability will be only 75%. To diagnose the early stages of the disease, it is advisable to use an ELISA test. The assay is an enzyme immunoassay with high sensitivity to antibodies. The reliability of the result is close to 100%, a false positive result in the presence of other diseases is excluded.

Negative test results for sexually transmitted diseases mean that the person is healthy. Doubtful analysis for syphilis will lead to a second examination. If there are factors that could affect the final conclusion, such as the presence of other diseases, the doctor will change the parameters of the test. A positive test result for syphilis is not a sentence or a reason for panic. With the help of medication, the disease can be completely cured. However, it should be remembered that diseases at an early stage are much better treated.

In contact with

A positive Wasserman reaction in most cases indicates the presence of syphilis in the patient. However, there are cases when the result is positive in the absence of the disease. In this case, an additional examination is prescribed.

In what cases is it assigned

An examination is ordered when there is a suspicion or need to exclude the presence of an infectious sexually transmitted disease such as syphilis. Also, the analysis is prescribed in the process of treating this disease in order to monitor its effectiveness.

Indications for examination are:

the presence of symptoms of the disease;
casual sex;
drug use;
the presence of contact, including household, with an infected person;
control of the treatment;
pregnancy at any time, as well as its termination;
swollen lymph nodes, accompanied by high fever;
donation of blood, sperm, tissues and organs;
being in places of deprivation of liberty and in a psychiatric clinic;
work as a medical staff, in trade, in education and in the social sphere;
hospitalization, including as an accompaniment of a child;
examine children whose mothers are infected.

How is it carried out

Blood is donated on an empty stomach. The last meal should be no later than 8 hours before the examination. 8 hours before donating blood, you need to stop eating fatty foods, alcoholic beverages, drugs. It is forbidden to carry out diagnostics if a foreign serum has been introduced to the patient. For analysis, venous blood is taken in a volume of 8 ml. If the analysis is taken from an infant, then the cranial or jugular vein is used.

The Wasserman blood test is based on the reaction of the immune system to the causative agent of the disease. If a person is infected, then when a person is added to his blood serum, which contains antibodies to syphilis, an artificial protein (cardiolipin antigen) and a binding protein (complement), a reaction occurs during which a precipitate forms. The precipitate is formed due to the presence of antibodies that the body has developed to fight the disease.

The absence of sediment means a negative result, the presence of a positive result. If a small amount of precipitate has fallen, then the reaction is considered doubtful. When positive analysis blood for RV, the serum is diluted 2 more times to understand in which dilution the reaction occurred. This allows you to determine how many syphilis bacteria are in the body.

Deciphering the results

Deciphering the results of the analysis is carried out by the attending physician. The result can be negative, positive, controversial. But not always a positive reaction means the presence of a disease.

RW negative rate

The norm is complete hemolysis, that is, the destruction of red blood cells. If this happens, then the reaction is negative. During the decoding of a blood test during the rapid diagnosis of syphilis (EDS), it must be borne in mind that during the first 2 weeks after infection, RW will be negative. The exception is the hidden secondary period, when the result temporarily changes from positive to negative.

RW positive

A positive reaction is indicated by a "+" sign. The number of pluses can be different - it depends on the degree of probability of the disease. In the case of primary infection, the reaction becomes positive at the seventh week of illness. Some patients have RW positive as early as the fifth week. If syphilis is secondary, then the examination will show the presence of infection immediately.

If the patient has a latent secondary period, then the reaction may turn negative, but then during the relapse, a precipitate will form again, indicating the presence of the disease. In the case of the congenital nature of the disease, the diagnosis will lead to a positive result.

Diagnosis is also carried out in order to control the ongoing treatment. There are cases when, despite the ongoing therapy, the reaction remains positive. This phenomenon is called seroresistant syphilis. In this case, such diagnostics does not provide an answer to the question of the destruction of the infection, and it is no longer carried out.

RW false positive

There are situations when a person who does not have a sexually transmitted disease, the result of the examination is positive. This happens if for some reason the immune system begins to destroy its own cells. Then, during the diagnosis, antibodies, characteristic diseases, are detected. This phenomenon is called a false positive Wasserman reaction.

The reasons for getting a false result can be:

viral and infectious diseases, including intestinal infections and tuberculosis, including the period after recovery;
autoimmune systemic diseases;
inflammatory diseases of the cardiovascular system;
diabetes;
oncological diseases;
third trimester of pregnancy;
diseases of the circulatory system;
taking certain medications;
alcoholism and drug addiction;
eating fatty foods before taking the test;
period of menstruation.

Thus, when obtaining a result indicating the presence of syphilis, it is necessary to exclude the possibility of an unreliable reaction and conduct additional examinations.

In contact with