Are there errors in the analysis? Questionable, false or erroneous syphilis test

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Love asks:

After intercourse, I began to have bloody discharge (2-3 drops of blood), for me it seemed unnatural, I went to the doctor. According to the results of the analysis, Trichomonas were found. But there are no signs: no itching, no discharge, no smell, no burning , in general, all the signs that are described, I don’t have them !!!, but the result shows the opposite?! Yes, and one more thing: for example, they took an analysis from me on the 17th, and on the 19th I started PMS, could this have affected ???, and what should I do? Should I start treatment? What I personally doubt! (when the doctor examined me, he generally said that I was pregnant ........) Can trichomonas tests be ERRONOUS? And how long does it take for the disease to show up?

Please specify by what method the study for trichomoniasis was carried out, and if possible, give the results of the examination in full.

Love asks:

It was not a specific test for trichomoniasis, I came to the appointment and complained about "bloody discharge", the doctor just took a smear, and the results were handed over to me from the laboratory. not detected, b) cells of epithelium - 2-3.4, c) leukocytes - 20-35, d) flora-mix, e) TRICHOMONADS - DETECTED, f) atypical cells - not detected. 2. ZALOSI (written in Ukrainian) -a) Neisser's gonococcus - not found, b) cells of epithelium - 3-4.5, c) leukocytes - entirely, d) flora - mixed, e) TRICHOMONADS - DETECTED, f) atypical .cells-not detected. In column 3. URETRA, only leukocytes are indicated, but I can’t make out what is written there. But I repeat once again, the smear was taken the day before PMS.

tatiana asks:

there was itching on the genitals. I went to the gynecologist. First time I took a pap smear. He didn't reveal anything. The doctor said to drink beer with salted fish at night. The next day she again passed a smear. Showed Trichomonas. I'm shocked. Husband vomits and mosques. I don't walk. He too. They said they had recently been infected.

Unfortunately, the disease of trichomoniasis is possible only after sexual contact with an infected partner. In this case, I recommend that you undergo treatment together with your spouse. You can learn more about this disease, ways of infection and treatment from the thematic section of our website.

Human chorionic gonadotropin, better known as hCG, is a hormone that begins to be produced in a woman's body as soon as pregnancy occurs. After attaching the fetal egg to the uterine wall, it is hCG that begins to control the process of its growth and development, this happens on the sixth to eighth day after fertilization.

HCG allows the corpus luteum, which produces progesterone, which contributes to the normal bearing of the child, not to resolve until the moment when the placenta is capable of self-producing hormones at the beginning of the second trimester.

In addition to stimulating the production of progesterone in large quantities, hCG acts as a natural antidepressant that helps the expectant mother cope with global restructuring in the body, and also blocks uterine contractions that can cause miscarriage in the early stages. It is thanks to him that the body of the expectant mother does not perceive the embryo as a foreign body that needs to be disposed of.

Normally, it is contained even in men, since the pituitary gland contributes to its production, but in a very small amount, less than 5 mU / ml. This figure is normal for non-pregnant women. When menopause occurs, the average concentration of hCG rises to 9 mU / ml, for those who are expecting a child, the hormone level grows exponentially, slowing down only closer to the middle of the period.

Blood analysis

A woman who suspects that she is pregnant, first of all, buys a test that is used at home. It reacts to the increased content of hCG in the blood, which is the cause of the second strip on the test. But the result of such a check may be incorrect if the woman used the pregnancy test too early or it turned out to be defective. That is why when you delay menstruation, you need to donate blood as soon as possible.

A blood test for hCG is more accurate - in 99% it shows the correct result, and the remaining percentage falls on various pathologies and hormonal disorders. A special advantage of this method is that an increase in the level of hCG is detected at the earliest possible time, when conception cannot yet be determined using a test strip.

In addition to determining pregnancy, hCG analysis is used as a means to determine missed pregnancy, and a triple test is used to detect developmental pathologies in the fetus from 14 to 18 weeks: for hCG, estriol and alpha-fetoprotein. Thus, abnormalities in the development of internal organs, as well as Down, Edwards and Shereshevsky-Turner syndromes are detected.

How to prepare for the analysis?

The veracity of the results directly depends on proper preparation. A gynecologist is obliged to tell you in detail about it, but there are general recommendations that should be followed.

The analysis for hCG is taken mainly in the morning, you can’t have breakfast before that. If it is not possible to donate in the morning, you can come to the laboratory at lunchtime, but the last meal should be no earlier than five hours before blood sampling from a vein. Be sure to tell your doctor before getting a referral for analysis about all the drugs you take, especially hormonal ones, as well as about existing diseases and abnormalities in the body, since this can significantly affect the results. Before passing the analysis, it is necessary to give up alcohol and smoking, physical activity and sexual intercourse.

Typically, the laboratory processes the results of the analysis quickly, they can be obtained in a few hours, and the maximum period is a couple of days. The attending physician will help to decipher them. It is important to remember that the level of hCG during the bearing of a child is purely individual, the main thing is to monitor the dynamics of changes in the concentration of the hormone.

False analysis results

Since even this type of test is not 100% reliable, many women are interested in whether the analysis can be wrong, and in what cases this happens. Sometimes the result of the analysis for hCG is misinterpreted by the doctor, who looked at too high values, not taking into account other reasons for the increase in the level of the hormone, including tumor formations. Therefore, it is necessary to donate blood again after a while, so as not to make a mistake and confirm the fact of conception. With the normal development of the fetal egg, the concentration of the hormone doubles or triples every week, and if this does not happen, then an ectopic or missed pregnancy is possible. Also, stopping the growth of hCG levels can cause a miscarriage in the early stages.

The analysis can be erroneous if a woman takes hormonal drugs, so the doctor must find out before donating blood, otherwise there is a chance that a false positive or negative result will be obtained. A recent abortion is also one of the factors that increase the likelihood that an error will occur.

Incorrect negative hCG test

When a woman suspects pregnancy, she first of all does a home test, and also donates blood. Imagine her surprise when she discovers that with a positive test, hCG is negative. How to understand which result is more true? Can HCG be wrong?

The main reason for a negative test result in the actual presence of pregnancy is too early blood donation, that is, if you come to the antenatal clinic on the first or second day of a delay in menstruation, the laboratory analysis is not able to show any dynamics in the level of hCG, because at this time the fetal egg has not yet attached in the uterus and has not begun to promote the release of the hormone.

In addition to this reason, a false negative result can occur if:

• Ovulation occurred much later than it should have;
• The embryo implanted too late in the uterine wall;
• Pregnancy is ectopic;
• For various reasons, the hormonal background and the rate of hCG synthesis have changed;
• There is no pregnancy at all.

If such discrepancies between the test strip and the result of the analysis occur, it is necessary first of all to do an ultrasound examination of the pelvic organs in order to exclude anomalies and the onset of an ectopic pregnancy, which requires immediate removal, otherwise the embryo will rupture the fallopian tube as it grows, which threatens with complications and even death from profuse bleeding. If this diagnosis was not confirmed, but a negative result was still obtained, then it is worth donating blood from a vein again in a week or two.

False positive hCG test

In addition to cases when, by all indications, a woman is expecting a baby, but the result of a blood test does not confirm this, a situation may arise when the hCG test is positive, and the test does not show pregnancy. And again the question arises, can the analysis of hCG be a witness to an “interesting situation”, but the test is not?

Most often, in such cases, the analysis determines the presence of pregnancy in its real absence (those scenarios when the home test strip turned out to be defective do not need to be taken into account). This situation can arise for various reasons:

• The woman was taking hCG-based drugs for the treatment of infertility;
• The body itself began to produce more hormone;
• Tumor formations;
• Substances similar to hCG in their composition and properties were found in the blood.

In the case of treatment with the use of hCG, you need to wait a few days until the hormonal background returns to normal. If during the examination the above diseases or anomalies in the body were not found in a woman, then the result may not be erroneous. But this can only be confirmed by repeated blood donation.

Despite the fact that there is a possibility of obtaining an incorrect result of the analysis for hCG, in modern medicine there has not yet been invented a way to more accurately determine the conception that has occurred. That is why you should not postpone a visit to the laboratory for a long time, since monitoring the dynamics of the hormone level will help to detect deviations in the development of the embryo when it can still be prevented.

Bibliography

1. Emergency care in obstetrics and gynecology: a brief guide. Serov V.N. 2008 Publisher: Geotar-Media.
2. Arterial hypertension in pregnant women Preeclampsia (preeclampsia). Makarov O.V., Volkova E.V. RASPM; Moscow; TsKMS GOU VPO RGMU.-31 p.- 2010.
3. Gestagens in obstetric and gynecological practice. Korkhov VV, Tapilskaya NI 2005 Publisher: Special Literature.
4. Emergency conditions in obstetrics. Sukhikh V.N., G.T. Sukhikh, I.I. Baranov et al., Publisher: Geotar-Media, 2011.

Can a hepatitis C test be wrong? Unfortunately, such cases sometimes happen. This pathology is dangerous because after infection, symptoms are often absent in a person for many years. Accuracy in the diagnosis of hepatitis C is especially important, since if it is not detected and treated in time, the disease leads to catastrophic complications: cirrhosis or liver cancer.

Types of diagnostics

Hepatitis C viruses are transmitted through the blood, so its analysis is important. The immune system produces protein antibodies against pathogens - immunoglobulins M and G. They are markers by which a liver infection is diagnosed using enzyme-linked immunosorbent assay (ELISA).

About a month after infection or during an exacerbation of chronic hepatitis C, class M antibodies are formed. The presence of such immunoglobulins proves that the body is infected with viruses and rapidly destroys them. During the patient's recovery, the number of these proteins is steadily declining.

Antibodies G (anti-HCV IgG) are formed much later, in the period from 3 months to six months after the invasion of viruses. Their detection in the bloodstream indicates that the infection happened a long time ago, so the severity of the disease has passed. If there are few such antibodies and in the re-analysis it becomes even smaller, this indicates the recovery of the patient. But in patients with chronic hepatitis C, immunoglobulins G are always present in the circulatory system.

In laboratory tests, the presence of antibodies to non-structural viral proteins NS3, NS4 and NS5 is also determined. Anti-NS3 and Anti-NS5 are detected early in the disease. The higher their score, the more likely it is to become chronic. Anti-NS4 helps determine how long the body has been infected and how severely the liver is affected.

A healthy person has no blood tests. Each of these liver enzymes indicates an early stage of acute hepatitis. If both are found, then this may signal the onset of liver cell necrosis. And the presence of the GGT enzyme (gamma-glutamyl transpeptidase) is one of the signs of organ cirrhosis. Evidence of the destructive work of viruses is the presence in the blood of bilirubin, the enzyme alkaline phosphatase (alkaline phosphatase), and protein fractions.

The most accurate diagnosis, if carried out correctly, is by PCR (polymerase chain reaction). It is based on the detection of not immune antibodies, but the structure of RNA (ribonucleic acid) and the genotype of the causative agent of hepatitis C. 2 variants of this method are used:

• qualitative - is there a virus or not;
• quantitative - what is its concentration in the blood ().

Deciphering the results

"Hepatitis C test is negative." This formulation confirms the absence of the disease in a qualitative study by PCR. A similar result of a quantitative ELISA test shows that there are no virus antigens in the blood. In immunological studies, their concentration is sometimes indicated below the norm - this is also a negative result. But if there are no antigens, but there are antibodies to them, this conclusion signals that the patient has either already had hepatitis C or has recently been vaccinated.

"Hepatitis C test positive." This wording needs clarification. A laboratory can give a positive result to a person who once had it in an acute form. The same wording applies to people who are currently healthy but are carriers of the virus. Finally, it may be a false analysis.

In any case, it is necessary to conduct a study again. For a patient with acute hepatitis C who is on treatment, the doctor may prescribe testing every 3 days to monitor the effectiveness of therapy and the dynamics of the condition. A patient with a chronic illness should take control tests every six months.

If the result of the antibody test is positive and the conclusion of the PCR test is negative, the person is considered to be potentially infected. To verify the presence or absence of antibodies, diagnostics are carried out using the RIBA method (RIBA - recombinant immunoblot). This method is informative 3-4 weeks after infection.

Options for false analyzes

In medical practice, there are 3 options for inadequate results of a diagnostic study:

• doubtful;
• false positive;
• false negative.

The enzyme immunoassay method is considered very accurate, but sometimes it gives erroneous information. Doubtful analysis - when the patient has clinical symptoms of hepatitis C, but there are no markers in the blood. Most often this happens when the diagnosis is too early, because the antibodies do not have time to form. In this case, a second analysis is done after 1 month, and a control one after six months.

The doctor receives it when class M immunoglobulins are detected by the ELISA method, and the virus RNA is not detected by the PCR method. Such results are often found in pregnant women, patients with other types of infection, and cancer patients. They also need to be retested.

False-negative results appear very rarely, for example, in the incubation period of the disease, when a person is already infected with the hepatitis C virus, but is also immune to it and symptoms are still absent. Such results can be in patients who take drugs that suppress the body's defense system.

What else is determined in the diagnosis?

Hepatitis C progresses differently depending on the genotype of the virus. Therefore, during the diagnosis, it is important to determine which of the 11 variants is in the patient's blood. Each genotype has several varieties, which are assigned letter designations, for example, 1a, 2c, etc. You can accurately select the dosage of drugs, the duration of treatment, by recognizing the type of virus.

In Russia, genotypes 1, 2 and 3 are predominantly common. Of these, genotype 1 is treated the worst and the longest, especially subtype 1c. Variants 2 and 3 have more favorable forecasts. But genotype 3 can lead to a severe complication: steatosis (fatty liver). It happens that a patient is infected with viruses of several genotypes at once. At the same time, one of them always dominates over the others.

Diagnosis of hepatitis C is indicated if:

Causes of erroneous analyzes

False positive tests, when there is no infection in the body, but the results indicate its presence, make up to 15% of laboratory tests.

Causes of errors:

False positive test results are possible if the expectant mother:

• metabolism is disturbed;
• there are endocrine, autoimmune diseases, flu and even a common cold;
• specific pregnancy proteins appear;
• the level of trace elements in the bloodstream decreases sharply.

In addition, when testing for hepatitis C, the causes of errors may lie in the human factor. Often affected:

• low qualification of the laboratory assistant;
• erroneous analysis of someone else's blood;
• low-quality chemicals;
• outdated medical devices;
• contamination of blood samples;
• violation of the rules of their transportation and storage.

Any laboratory can make mistakes sometimes. But this is possible with only ELISA tests or only PCR. Therefore, when diagnosing a disease, both research methods should be used. Then it is most reliable, since it is difficult to make a mistake if there is no virus in the blood.

It is important to test for hepatitis C when there are no ailments, even a mild cold. It is not required to donate blood on an empty stomach. You should only give up fatty, fried, spicy foods the day before, do not drink alcohol. One last thing: an initial false-positive result for hepatitis C is not a reason to panic. The conclusion should be made only after additional research.

December 1 is World AIDS Day. On the eve of this date, the Russian Ministry of Health cited frightening statistics, according to which the number of cases in just 15 years will increase by 2.5 times. HIV prevention is now one of the main areas of modern medicine, aimed at stopping the spread of the virus. And, first of all, you need to start with analyzes. AiF.ru found out where you can get tested for HIV and how to do it correctly so as not to get a false result.

Two types of verification

There are two main types of HIV/AIDS tests: enzyme immunoassay and PCR diagnostics. Both are informative and accurate.

Immunoenzymatic analysis today is the most common. It is based on the detection of antibodies to HIV in the patient's blood serum. In most patients, they appear approximately 4-6 weeks after infection, in 10% - after 3-6 months, and in 5% - later. Therefore, ideally, this analysis should be taken three times every 3 months.

PCR diagnostics is a polymerase chain reaction test that can check blood serum, antiviral RNA or DNA, and quantify CD-4 lymphocytes. At the same time, doctors often call PCR analysis the only possible early diagnosis of HIV infection, which is carried out, including in babies of the first year of life. The advantage of this research method is the fact that it can detect the virus in the incubation and early clinical period, when there are no antibodies in the blood yet. This helps to start treatment earlier and reduce the negative impact of the disease.

How to prepare?

You need to prepare for an HIV/AIDS test. Donate blood should be on an empty stomach, while the last meal should take place no later than 8 hours. Naturally, it is recommended to endure a kind of diet, refusing a few days before blood donation from alcohol and "harmful" foods - fatty, fried, smoked meats, marinades and other refined foods.

It should be borne in mind that if you are unwell, even with any viral or infectious disease, it is better not to donate blood or come back for analysis 35-40 days after recovery. Otherwise, there is a risk of getting a false positive result.

An HIV/AIDS test goes through several stages of verification. Therefore, they prepare it for 2-10 days.

negative plus

The result can be positive, negative and questionable. In the latter case, it is worth retaking the analysis a little later.

Doctors say that with a positive result, it is impossible to immediately declare that a person has HIV or AIDS. Indeed, in some cases, indicators may be overestimated for other reasons. In this situation, you should retake the analysis again - everyone who has a result with a “+” sign goes through this procedure.

Where does the "false signal" come from? Due to certain diseases and conditions that can cause cross reactions. For example, due to an allergy in the blood, antigens that are incomprehensible to the body can be produced, which it recognizes as foreign.

Also, a similar reaction can occur due to a sharp change in the composition of the blood - for example, due to a jump in cholesterol (with excessive consumption of fatty foods, fried foods, seeds), hormonal imbalance (in particular, during menstruation in women), infections (respiratory tract diseases, the presence of hepatitis and influenza viruses, recent vaccinations, tuberculosis), excessive blood density, arthritis, oncology. Fungi, viruses, and bacteria can also contribute to incorrect data. In addition, a false positive result may appear due to medical errors: in case of violation of the rules for blood sampling and transportation, the use of low-quality serum and improper storage of the material.

Degrees of anonymity

If you wish, you can take an analysis for the immunodeficiency virus at any time. However, there are a number of provisions when it is recommended to do this. So, it is worth donating blood when planning a pregnancy, before a planned operation, after dubious injections, unprotected sexual contact with an unfamiliar person, with a sharp deterioration in well-being.

You can get tested at any clinic, private clinics and diagnostic centers, as well as specialized AIDS centers. Moreover, in state medical institutions, this procedure will be completely free. Any citizen of the country, regardless of where he lives, can take tests at the AIDS center.

There are two types of testing: confidential and anonymous. In the first case, a person gives his name to the laboratory assistants. In the second case, he is assigned an identification number. All results are given exclusively to the patient, and even with a positive result, the laboratory cannot inform anyone - this will be regarded as a violation of medical secrecy. In paid clinics, the principle of taking tests is no different, only in this case the service is provided for money. The cost is from 400 to 3,400 rubles, depending on the complexity and verification options.

In May 2016, it became known about the complete and final collapse of one of the most sensational start-ups in the field of healthcare - the Theranos project. The company promoted a technique to detect 240 diseases by a drop of blood from a finger using its own Edison device. The founder and head of the project, a young American, Elizabeth Holmes, admitted that the test results sent to hundreds of thousands of patients were incorrect, and announced the mailing of corrected results.

The story is unusual from all angles, but what is most striking is the scale of the "mistake" - perhaps something that laboratory diagnostics has not yet seen. And how often in ordinary life do we encounter analysis errors and why do they happen at all? Who is to blame for them - the laboratory assistant, the failure of the equipment, or maybe even the patient himself? MedAboutMe understood the nuances of laboratory diagnostics.

Most often, staff errors are associated with their low qualifications. For example, you can talk about errors in sampling:

• Too tight tourniquet, incorrect body position can affect the results of studies of carbohydrate, lipid metabolism, etc.
• Violations of technology: for example, the use of conventional test tubes when testing blood for glucose leads to the fact that its level decreases by 10% after 20 minutes, that is, long before the end of testing. And if the procedure for changing tubes is violated, a reagent that should not be there can get into the sample, which affects the results.

Errors in the documentation are associated with illegible records and incorrect identification of the patient. Cases of giving test results to the wrong person are not uncommon in laboratories.

Separately, it is necessary to point out the violation of the temperature regime for the delivery and storage of samples. For example, the sampling of biomaterial for some complex analyzes may be carried out in a branch of a large network of laboratories or in a polyclinic, after which the blood must be delivered to the central department, where there is a possibility for its analysis. That is, the sample must move along the street - in winter at low temperatures or in summer at high temperatures. And, for example, an analysis for adrenocorticotropic hormone requires the use of deep freezing of a blood sample, and the cooler bag in which the samples are transported maintains a temperature of at least -3-4 ° C. In addition, it is not uncommon for samples to arrive at the central office with a delay - due to the lack of a special delivery service, for example - which also increases the risk of an erroneous result.

Finally, errors associated with the low qualification of personnel are possible during the actual analysis. Violation of sterility standards, contamination (contamination) of samples, improper preparation of reagents and other technological errors - all of them also increase the risk of obtaining an unreliable result.