Anti hcv core positive ns 3. Hepatitis C, anti-HCV sums

Viral liver lesions today often appear in the practice of gastroenterologists. And the leader among them, of course, will be hepatitis C. When it enters the chronic stage, it causes significant damage to liver cells, disrupting its digestive and barrier functions.

Hepatitis C is characterized by a sluggish course, a long period without the manifestation of the main symptoms of the disease and a high risk of complications. The disease does not reveal itself for a long time and can only be detected by testing for antibodies to hepatitis C and other markers.

The virus affects hepatocytes (liver cells), causing their dysfunction and destruction. Gradually, having passed the stage of chronicity, the disease leads to the death of a person. Timely diagnosis of a patient for hepatitis C antibodies can stop the progression of the disease and improve the patient’s quality and life expectancy.

Antibodies to the hepatitis C virus detected in time can diagnose infection at its most primary stage and give the patient a chance for a complete cure.

What are antibodies to hepatitis C?

People not involved in medicine may have a natural question - hepatitis C antibodies, what are they?

The virus of this disease contains a number of protein components in its structure. When these proteins enter the human body, they cause a reaction from the immune system and antibodies to hepatitis C are formed. There are different types of antibodies, depending on the type of the original protein. They are determined in the laboratory at different periods of time and diagnose different stages of the disease.

How is the hepatitis C antibody test performed?

To detect antibodies to, a person's venous blood is taken in the laboratory. This study is convenient because it does not require any preliminary preparation, except for abstaining from eating 8 hours before the procedure. The blood of the subject is stored in a sterile test tube, after which the corresponding immunoglobulins are detected using the enzyme-linked immunosorbent assay (ELISA), based on the antigen-antibody relationship.

Testing for antibodies to hepatitis C is an option for primary screening for the presence of this infection in a person.

Indications for diagnostics:

liver dysfunction, patient complaints;
increase in indicators of liver function in biochemical analysis - transaminases and bilirubin fractions;
preoperative examination;
pregnancy planning;
questionable ultrasound diagnostic data of the abdominal organs, in particular the liver.

But hepatitis C antibodies are often discovered in the blood completely by accident, during an examination of a pregnant woman or during a planned operation. For a person, this information in many cases comes as a shock. But there is no need to panic.

There are a number of cases when both false-negative and false-positive diagnostic results are possible. Therefore, after consultation with a specialist, it is recommended to repeat the questionable analysis.

If antibodies to hepatitis C are detected, you should not expect the worst. You should seek advice from a specialized specialist and conduct additional examinations.

Types of antibodies to hepatitis C

Depending on the antigen to which they are formed, antibodies for hepatitis C are divided into groups.

Anti-HCV IgG - class G antibodies to the hepatitis C virus

This is the main type of antibody detected to diagnose infection during initial screening of patients.“These markers of hepatitis C, what are they?” - any patient will ask the doctor.

If these antibodies to hepatitis C are positive, then this indicates that the immune system has encountered this virus before; a sluggish form of the disease without a clear clinical picture may be present. At the time of sampling, there is no active replication of the virus.

The detection of these immunoglobulins in human blood is the reason for additional examination (detection of RNA of the causative agent of hepatitis C).

Anti-HCV core IgM - class M antibodies to HCV core proteins

This type of marker begins to be released immediately after the pathogenic microorganism enters the human body. It can be traced in the laboratory a month after the infection. If antibodies to hepatitis C class M are detected, then the acute phase is diagnosed. The number of these antibodies increases at the time of weakening of immunity and activation of the virus during the chronic process of the disease.

When the activity of the pathogen decreases and the disease becomes chronic, this type of antibody may no longer be detected in the blood during research.

Antibodies to hepatitis C

Anti-HCV total - total antibodies to hepatitis C (IgG and IgM)

In practical situations, this type of research is often used. Total antibodies to the hepatitis C virus represent the detection of both classes of markers, both M and G. This analysis becomes informative after the accumulation of the first class of antibodies, that is, 3-6 weeks after the fact of infection. On average, two months after this date, class G immunoglobulins begin to be actively produced. They are detected in the blood of a sick person throughout his life or until the virus is eliminated.

Total antibodies to hepatitis C are a universal method of primary screening of the disease one month after a person is infected.

Anti-HCV NS - antibodies to non-structural proteins of HCV

The markers indicated above belonged to the structural protein compounds of the hepatitis C pathogen. But there is a class of proteins called non-structural. They can also be used to diagnose the patient’s disease. These are NS3, NS4, NS5 groups.

Antibodies to NS3 elements are detected at the very first stage. They characterize the primary interaction with the pathogen and serve as an independent indicator of the presence of infection. Long-term persistence of these titers in a large volume may be an indicator of an increased risk of the infection becoming chronic.

Antibodies to the NS4 and NS5 elements are detected in late periods of disease development. The first of which indicates the level of liver damage, the second - the launch of chronic mechanisms of infection. A decrease in the titers of both indicators will be a positive sign of the onset of remission.

In practice, the presence of non-structural hepatitis C antibodies in the blood is rarely checked, as this significantly increases the cost of the study. More often, core antibodies to hepatitis C are used to study the condition of the liver.

Other markers of hepatitis C

In medical practice, there are several other indicators by which to judge whether a patient has the hepatitis C virus.

HCV-RNA - hepatitis C virus RNA

The causative agent of hepatitis C is RNA-containing, so it is possible to detect the pathogen gene itself in the blood or biomaterial taken during a liver biopsy using reverse transcription.

These test systems are very sensitive and can detect even one single virus particle in a material.

In this way, it is possible not only to diagnose the disease, but also to determine its type, which helps to develop a plan for future treatment.

Antibodies to hepatitis C: interpretation of the analysis

If a patient has received the results of an enzyme-linked immunosorbent assay (ELISA) test for hepatitis C, he may wonder: what are hepatitis C antibodies? And what do they show?

When examining biomaterial for hepatitis C, total antibodies are not normally detected.

For quantitative assessment in medical practice, the positivity coefficient R is used. It reflects the optical density of the sample in the biomaterial. If its value is greater than 1, the result is considered positive. If it is less than 0.8, it is considered negative. An R value of 0.8 to 1 is questionable and requires additional diagnostics.

Let's look at examples of ELISA tests for hepatitis C and their interpretation:

Test results

Interpretation

HCV IgG cor 16.45 (positive)

Anti-HCV IgG NS3 14.48 (positive)

Anti-HCV IgG NS4 16.23 (positive)

Anti-HCV IgG NS5 0.31 (negative)

There are high titers of antibodies to the hepatitis C virus in the blood. The presence of the disease is likely. PCR diagnostics are required to confirm the diagnosis and determine the type of pathogen.

Anti-HCV IgG cor 0.17 (negative)

Anti-HCV IgG NS3 0.09 (negative)

Anti-HCV IgG NS4 8.25 (positive)

Anti-HCV IgG NS5 0.19 (negative)

НBsАg (Australian antigen) 0.43 (negative)

IgM antibodies to HAV 0.283 (negative)

Antibodies to hepatitis C are present in the blood. The result is questionable. To clarify the diagnosis, it is necessary to conduct PCR diagnostics

As can be seen from the table, if antibodies to hepatitis C are still detected, then the interpretation of the analysis should only be carried out by a specialist. Depending on the type of markers identified in the biological material of the subject, we can talk about the presence of the disease and the stage of its development.

The enzyme immunoassay method is quite accurate and in most cases reflects the true clinical picture of the patient’s condition. However, it is sometimes characterized by false negative and false positive results.

False-positive markers are periodically found in the blood of pregnant women, cancer patients, and people with a number of other types of infections.

False-negative test results are almost never encountered and may occur in patients with immunodeficiency and those taking immunosuppressive drugs.

The result is considered doubtful if there are clinical signs of the disease in the subject, but there are no markers in the blood. This situation is possible with early diagnosis using the ELISA method, when antibodies have not yet had time to be developed in a person’s blood. It is recommended to conduct a second diagnosis a month after the first and a follow-up test after six months.

If positive antibodies to hepatitis C are detected, then they may indicate that the patient has previously had hepatitis C. In 20% of cases, this disease is transmitted latently and does not become chronic.

What to do if antibodies to hepatitis C are detected?

But what if some immunoglobulins were nevertheless identified? Don't panic or get upset! You need an in-person consultation with a specialized specialist. Only he is able to competently decipher the designated markers.

A qualified doctor will always check the patient for all possible false negative and false positive results in accordance with his medical history.

A follow-up examination should also be scheduled. If titers are initially detected, the analysis can be repeated immediately. If it confirms the previous one, research with other diagnostic methods is indicated.

Additional diagnostics of the patient’s condition are also carried out six months after the first blood donation.

And only by using an expanded list of tests, face-to-face consultation with a specialist and confirmed results after a period of time can one diagnose the infection of the person being examined with the virus.

In this case, together with the determination of markers in the blood, it is advisable to monitor the patient’s condition using the PCR method. Testing for antibodies to hepatitis C is not an absolute criterion for the presence of the disease. It is also necessary to analyze the general clinical picture of the person’s condition.

Useful video

The following video provides additional information about testing for antibodies to hepatitis C:

Conclusion

Antibodies to the hepatitis C virus in a person’s blood provide detailed information about his contact with this pathogen. Depending on the types of markers, the specialist will always determine the stage of the disease, the type of pathogen and offer the best treatment plan.

With effectively selected therapy and early diagnosis of infection using ELISA, it is possible to prevent the disease from becoming chronic. Therefore, it is recommended for everyone to periodically undergo screening tests to detect antibodies to hepatitis C in the blood.

Serology

Hepatitis C– a viral infection caused by the RNA-containing hepatitis C virus (HCV, HCV). The source is a sick person.

Transmission routes:
A). transfusion - after blood transfusion;
b). from mother to fetus and newborn;
V). sexual tract;
G). during manipulations that damage the integrity of the skin and mucous membranes.

The response to the appearance of virus antigens in the body is the production of specific antibodies anti-HCV sum. The dynamics of the appearance of anti-HCV in the blood of infected individuals is variable, the average interval from the onset of the disease to the appearance of antibodies is about 15 weeks (4-32 weeks), anti-HCV in patients with chronic hepatitis is detected for a long time, more than 7 years.

7 genotypes of the virus have been identified with a predominant distribution in one or another region of the globe. Genotypes 1b, 2a, 2c are typical for Japan, 1a - in the USA and Southern Europe.
In Russia, genotypes 1b, 3a, 2a are most often registered. In this regard, HCV is very variable, which determines difficulties in treatment, vaccine prevention and diagnosis. In the external environment, HCV is much less stable than hepatitis A and B viruses.

Anti-HCV is a test for hepatitis C prescribed by a doctor in the process of diagnosing a viral infection. The test is based on the characteristics of the response of the human immune system when a pathogen enters cells. In this case, biologically active substances - immunoglobulins (in medical literature are usually abbreviated as Ig) are released into the blood.

The antibodies produced are specific, that is, their structure is clearly predetermined depending on the type of pathogen. This is the basis for the principle of serological enzyme immunoassay, which is called the anti-HCV ELISA test.

The structure and content of synthesized immunoglobulins is directly dependent on the structural units of the hepatitis C virion. HCV (hepatitis C virus) is a round-shaped pathogen, the diameter does not exceed 50 nm. In the middle there is one strand of RNA, covered with a capsid (core protein). On the outside, it is surrounded by a shell, the basis of the structure of which is lipids, and inclusions of glycoproteins E1 and E2 look like protrusions.

The structure of the virus genome can be represented as a diagram:

Modern HCV analysis is based on identifying several markers of infection. These are virus RNA, core antigen and specific antibodies. It is HCV RNA (viral hepatitis C) that is detected in the blood serum before others. The second most important indicator is the core antigen. It can be detected a week after the appearance of RNA in sufficient quantities for identification by test systems.

The sensitivity of the hepatitis C virus antigen test depends on the testing mechanism. With chemiluminescent detection it is significantly higher (up to 0.06 pg/ml) than with the classical immunoenzyme reaction using chromogen oxidation with peroxidase. But the higher the sensitivity of the analysis, the more expensive the testing system.

The level of viral RNA in the blood is closely related to the concentration of the core antigen. Thus, some methods allow you to determine the approximate viral load taking into account the correlation coefficient.

Specific antibodies to the hepatitis C virus are determined using screening enzyme immunoassay and immunoblotting test systems. The latter are characterized by higher specificity.

The approximate time for the appearance of virus RNA, antigen and various types of immunoglobulins is given in the table:

Most of the test systems currently used were developed in the early 1990s. If it is necessary to diagnose the virus, antigens obtained from samples of isolates from the 1990s corresponding to HCV genotype 1a are used. There is already information about the absence of antibodies to the core antigen, one of the most immunogenic HCV antigens, in some patients. This is associated with the appearance of certain mutations. Therefore, in order to exclude questionable results, you should contact laboratories that work with modern test systems (manufactured by Abbott, Bayer, etc.).

Anti-HCV: what is this test?

There are several types of diagnostic tests for hepatitis C, which are performed using a serological enzyme immunoassay.

Each of them provides the specialist with certain information. This:

suspected presence of the disease;
form of viral infection;
period from the moment of infection;
the reaction of the immune system to the penetration of a pathogen into the bloodstream;
the patient’s condition after taking medications or based on the results of independent recovery after the acute phase of the disease.

Description of the total antibody test

The study begins with the Anti-HCV Total test, designed to determine total antibodies (IgG + IgM). Carrying out other tests is advisable if anti-HCV is positive: what this means can only be determined by a doctor. The fact is that some patients have a false positive result, which requires additional examination.

Testing for antibodies to the main structural proteins of HCV

The most indicative blood test is for core-Ag. Immunoglobulins to this structural subunit appear earlier than others and serve as a specific laboratory marker of infection. But at the same time, if AT is not detected, this does not exclude infection. A negative result may be due either to a mutation in HCV itself or to the individual characteristics of the patient.

Further screening for hepatitis C includes an anti-HCV blood test to determine the spectrum of different types of immunoglobulins. Thus, the detection of IgM class antibodies indicates an acute course of infection, while anti-HCV IgG speaks in favor of a long-term, chronic or latent form of the viral disease. But the results should be interpreted by a specialist who will explain what kind of analysis it is and give recommendations for further examination and treatment.

Accuracy

The accuracy of enzyme immunoassay depends on the manufacturer of the diagnostic test systems. The professionalism of the medical staff also plays an important role. The specificity and reliability of such a study reaches 90%. Therefore, a positive test for hepatitis C carried out by the serological method clearly serves as an indication for further diagnosis.

But before donating blood for HbsAg HCV or other ELISAs, you need to ask what equipment the analysis will be used on. If you have any questions, it is better to consult a doctor. The quality of the research performed completely determines the tactics for further diagnostics.

Test method for hepatitis C

Enzyme immunoassay for hepatitis C is classified as a serological research method.

Test systems used to perform ELISA are divided into several groups depending on the types of antibodies used:

lysate, during the study, native antibodies obtained from culture are used;
recombinant, use protein structures synthesized using genetic engineering, similar in structure to the antigen under study;
peptide, artificially synthesized peptides are used.

As a solid phase, 96-well plates are usually used, less often polystyrene beads. ELISA is catalyzed by a number of specific biologically active enzymes.

The enzyme immunoassay is carried out in several stages:

The test sample is recognized by the antibody. The result is determined by the number of immune complexes formed or the remaining free sites of specific binding.
Formation of an enzyme-labeled compound.
Transformation of an enzyme label into a specific signal, which is recorded using any physicochemical method (spectrophotometry, fluorimetry, luminescence, etc.).

There are the following types of enzyme immunoassays performed to diagnose hepatitis C virus:

"sandwich" method;
indirect ELISA;
competitive ELISA method;
inhibitory ELISA;
direct ELISA.

The patient must first obtain a referral from a doctor. You can get tested in a private laboratory without the appropriate documents. Immediately before the test, the nurse records the patient's data and labels the tubes accordingly.

Blood is drawn from a vein. The skin is first treated with a sterile napkin with a disinfectant solution. After the procedure, the wound is sealed with a disposable plaster. The timing of the enzyme immunoassay reaction ranges from 1 to 5 days. The result can be collected either directly from the laboratory, or received electronically by email or using a code on the website.

Indications for ELISA

It is necessary to consult a doctor and subsequently donate blood for total antibodies to hepatitis C if specific signs of infection occur.

Pathology can be suspected based on the following symptoms:

almost never-ending feeling of fatigue;
sleep disorders (usually at night a person suffers from insomnia, and during the day - from drowsiness);
decreased concentration, slowed mental acuity;
decreased appetite;
an unpleasant feeling of fullness, heaviness and discomfort in the right hypochondrium;
digestive disorders accompanied by flatulence, stool disorders, heartburn, belching, unpleasant taste in the mouth;
yellowness (often, slight and quickly passing) of the skin, whites of the eyes.

But in more than half of those infected, the viral infection occurs without a pronounced clinical picture, and the symptoms that arise can easily be confused with acute respiratory viral infection or banal overwork. This is why hepatitis C is often discovered unintentionally during preparation for clinical examination.

Strict indications for donating blood for analysis are:

symptoms characteristic of liver dysfunction;
general malaise;
deviations from the norm when interpreting the results of liver tests;
contact with a person who has a confirmed diagnosis of hepatitis C (sexual intercourse, contact with blood or mucous membranes, etc.);
presence of HIV;
blood transfusion or organ transplant performed before 1992;
regular hemodialysis procedures;
diseases requiring frequent invasive medical procedures;
in children born from HCV-infected mothers;
registration of a medical record for military personnel, workers in the field of trade, healthcare, education, cosmetology, pharmacy.

ELISA is mandatory during pregnancy. The study is performed at 12 and 30 weeks.

Do not forget about such a concept as the “serological window”. This term refers to the period that elapses from the moment of infection to the time when the virus is detected, or more precisely, the antibodies produced to its antigens.

Repeated ELISA is prescribed when:

uncertain results of the first analysis;
undergoing antiviral therapy (to control antibody titer);
Anti-HCV Total negative, but symptoms of viral hepatitis persist.

According to experts, almost every visitor to a dental or cosmetology office is at risk of infection. Therefore, for the purpose of prevention, Anti HCV Total (determination of total antibodies by ELISA) is recommended to be taken annually.

How to prepare

The reliability of the obtained analysis results largely depends on the correct preparation of the patient. Expert recommendations include:

do not eat 12-14 hours before donating blood;
stop smoking 3-4 hours before the test;
donate blood in the morning;
after waking up, you should not drink anything except still water;
3-4 days before the test, exclude fatty foods, fried foods prepared with a lot of oil, “heavy” sauces (mayonnaise, tartar, etc., especially store-bought ones), fast food (including snacks and appetizers), sausages, smoked meats , dried, dried fish and/or meat, in general, the menu before analysis should be compiled according to diet No. 5;
7-10 days before ELISA, alcoholic drinks (regardless of strength) are strictly contraindicated.

In general, before donating blood, it is necessary to adhere to the principles of rational nutrition and, if possible, give up bad habits.

When contacting a doctor with test results, you must inform about all medications taken, possible violations of the rules for preparing for the study, and concomitant diseases. You should also talk about disturbing symptoms, even if, at first glance, they are not related to liver damage.

Decoding the results obtained

Anti HCV interpretation should be carried out by a specialized specialist (infectious disease specialist or hepatologist). Normally, there should be no antibodies to hepatitis C in the human body.

However, a false negative result is possible if:

period of the “serological window”;
concomitant immunodeficiency (with viral damage to the immune system, the production of antibodies stops);
oncological lesions of the hematopoietic system.

A false positive HCV AgAt ELISA result is sometimes noted when:

pregnancy (due to the production of specific protein compounds similar in structure to immunoglobulins);
autoimmune pathologies (in such diseases, the production of antibodies is unpredictable);
disorders of the hematopoietic system;
recovery from the acute phase of hepatitis C (in some people, the virus is destroyed by the immune system without drug therapy);
previous antiviral therapy (immunoglobulins can last up to 3-5 years or more);
in a child under 3 years of age at birth after pregnancy to an infected or treated mother;
concomitant severe infections (regardless of their etiology), in which case erroneous results are possible due to the massive release of antibodies in response to viral or bacterial tissue damage.

The interpretation of the results of the enzyme immunoassay can be presented in the form of a table:

Starting from 9 weeks	Result and description of possible pathology
Determination of total antibodies (Anti-HCV Total analysis)	Positive. Required: carrying out ELISA for IgG and IgM; performing high-quality PCR. Negative means the person is healthy. But confirmatory tests to exclude infection are PCR (qualitative determination of virus RNA) or repeat ELISA after 4-8 weeks.
Core-Ag ELISA	A positive result indicates recent infection
Anti-HCV IgM	A positive test is possible in acute hepatitis C. If IgG is detected at the same time, an exacerbation of a chronic viral process is likely
IgG (to various structural proteins)	Detection favors chronic HCV

If immunoglobulins are detected, their titer (concentration) must be indicated on the test results form. In this way, the doctor can judge the intensity of the pathological process and evaluate the immune response. But accurate information about the quantitative content of the virus in the human body can only be obtained by detecting RNA using the polymerase chain reaction method.

Modern medicine is based on the principles of overdiagnosis, this is due to the fact that very often the true cause of certain symptoms is not revealed during the initial examination or laboratory tests. Viral agents that infect liver cells are no exception, and hepatitis C, the treatment of which is expensive and does not always give a positive outcome, must be detected with one hundred percent probability in order to prevent its further spread.

HCV blood test, what is it?

This is an enzyme immunoassay , which makes it possible to detect antibodies and is usually indicated in the doctor’s referral as Anti-HCV. When conducting this study, it is possible to identify three classes of immunoglobulins, which provide insight into:

Presence of disease.
Stages of development - this refers to the incubation period, acute course or chronic form, as well as the presence of a disease already suffered without hospitalization and treatment.

The HCV test is based on the detection of different classes of immunoglobulins and allows you to determine antibodies to the causative agent of hepatitis C. Experts distinguish two classes of globular proteins that provide information about the stage of the disease - these are M and G.

The first indicates the acute phase of the development of the disease and its titer increases over the first few months after infection. At this stage, cure of the infection using the modern three-component regimen is observed in more than ninety-five percent of cases.

The second class speaks of the long-term persistence of the virus in liver cells. The chronic form of hepatitis C is considered the most prognostically unfavorable, since it is less treatable and it is rarely possible to completely eliminate viral particles from hepatocytes.

Methods for detecting hepatitis C virus

In addition to HCV analysis, it is possible to determine the presence of the so-called “gentle killer” in the blood in several other ways, including:

- is considered one of the most effective and accurate diagnostic methods. It allows you to detect the RNA of the virus in the human body and carried out even if the result is positive HCV analysis for definitive diagnosis .
Conducting a rapid test for the presence of hepatitis C pathogen- the sensitivity of this method is about ninety-six percent, which makes it possible to provide information about the presence of a pathogen in human biological environments in the shortest possible time.

There are also research methods that usually precede referral of a patient for HCV analysis. It is these diagnostic tools that provide information that leads a specialist to believe that there is inflammation of liver cells of viral etiology:

Ultrasound diagnostics and elastometry.
Clinical blood test.
Coagulogram.
Biochemical with liver tests.

Accuracy of anti-HCV blood test

Anti-HCV diagnostics is a modern and fairly accurate method, it allows you to determine the presence of the hepatitis C pathogen starting from the fifth to sixth week after infection. The virus will not be detected in plasma if it replicates less than two hundred copies per milliliter. If the calculation is carried out in international units, this is less than forty international units per milliliter. If there are more than a million viral particles in one milliliter of plasma, the presence of viremia is established.

A false positive result for carriage of the hepatitis C virus is established in approximately every tenth case. The reason for such statistics is a violation of the method of blood sampling and analysis, changes in hormonal levels, or non-compliance with the doctor’s recommendations for preparing for the test. According to WHO data, four percent of the world's population are convalescents with hepatitis C.

Possible indications for HCV analysis

To undergo testing for the presence of hepatitis C, you do not need permission or referrals from the attending physician; today there are many laboratories and medical centers where anyone can undergo an HCV blood test. However, there is a list of conditions that are indications for this study, these include:

Desire to become a donor.
A history of exchange transfusion of blood or its components.
An increase in the level of ALT and AST due to medical intervention.
Exclusion of hepatitis C in the presence of its secondary symptoms.
Determining the effectiveness of hepatitis C treatment.

It is necessary to take an HCV blood test no earlier than 5-6 weeks after the initial suspected infection, otherwise, even if there is an infection in the body, immunoglobulins may not be produced in sufficient quantities and give a false negative result.
It is necessary to take the test after a twelve-hour break in food - food intake affects the rheological characteristics of the plasma.
The sampling should be carried out in the morning - this is due to the fact that most of the standard indicators were calculated in the morning, so to reduce the likelihood of a false positive result, it is necessary to follow this rule.
It is necessary to exclude the use of hormonal, antiviral and cytostatic drugs during the day.
You should also refrain from drinking alcohol the evening before visiting the laboratory.

Methodology for conducting an HCV blood test and evaluating the result

To carry out the analysis, it is necessary to collect biological material, in this case it is blood. After twenty milliliters of blood is taken from a peripheral vein, it is centrifuged to obtain its liquid component - plasma, which will be examined. In order to prevent the development of false positive results, it is recommended to draw blood in the morning before eating. The results obtained from HCV analysis should be interpreted as follows:

Negative- this indicates the absence of antibodies to hepatitis C in the patient’s body, as a result - the person is healthy.
Positive- means that antibodies to hepatitis C viral particles are found in the patient’s blood, which may indicate the presence of the disease in acute or chronic form. However, even if a positive result is obtained, it is necessary to carry out.
1. The presence of IgG indicates a chronic form of the pathology.
2. The amount of detected IgM indicates the severity of the process - the more it is, the earlier the disease is considered.

PCR diagnosis of hepatitis C

The polymerase chain reaction is considered the most accurate and modern method for identifying RNA and DNA chains of any nature. Hepatitis C virus contains ribonucleic acid, and the frequent occurrence of false positive results in anti-HCV blood tests makes it an ideal candidate for this test.

There are qualitative and quantitative types of diagnostics, of which the second is the most indicative. The negative side of this diagnostic tool is its high cost, as well as the duration of the study, due to which the HCV blood test is the most affordable, and if it is performed correctly, the number of errors is minimal.

Viral hepatitis C is a serious medical and social problem. About 180 million people in the world today suffer from this disease, 350 thousand die every year. The long-term latent (asymptomatic) course of the disease leads to delayed diagnosis. An analysis for hepatitis C is carried out for the purpose of diagnosing the disease, differential diagnosis, and with its help, a previously suffered disease “on the legs” is determined.

The study is used in people with symptoms of hepatitis C, elevated levels of liver enzymes, when obtaining information about a previous disease of unspecified etiology, in people at risk and screening studies.

Diagnosis of hepatitis C is carried out in 2 stages:

Stage 1. Determination of the presence of antibodies to the virus (anti-HCV) in blood serum.

Stage 2. If anti-HCV is present, a test is performed for the presence of RNA (ribonucleic acid) using the PCR method for hepatitis C. The test allows you to identify the phase of the process - “active/inactive”, and decide on the need for treatment. It is known that about 30% of infected people get rid of the infection on their own, since they have a strong immune system and do not need treatment. Using PCR, the genotype of the virus is determined. Different genotypes respond differently to treatment.

The extent of liver damage is determined using a biopsy or other invasive and non-invasive tests (for example, fibrotest). The degree of liver steatosis is determined using a steatotest. In all cases, the diagnosis of hepatitis C should be based on data from an epidemiological investigation, the clinical picture of the disease and data from a biochemical blood test.

Rice. 1. Severe consequences of viral liver damage - intense ascites.

Test for hepatitis C: anti-HCV

Antibodies to viruses (anti-HCV) are specific markers of infection. In the body of a sick person, specific antibodies are produced to the viral proteins (antigens) - immunoglobulins of the IgM and IgG classes (anti-HCV IgM/IgG).

If a positive result for antibodies is obtained, a confirmatory test is performed - determining total antibodies to the structural and non-structural proteins of the virus. Anti-HCV IgM is produced for the structural envelope proteins of the virus E1 and E2, the nucleocapsid protein C - cor (anti-HCV IgG), and the 7 non-structural enzyme proteins NS (anti-HCV NS IgG).

An enzyme-linked immunosorbent assay (ELISA) is used to detect antibodies to the hepatitis C virus. To confirm (+) ELISA results, confirmatory tests are used - RIBA (recombinant immunoblotting), less often Inno-Lia (analysis of synthetic peptides).

Anti-HCV IgM test

IgM antibodies appear in the blood serum 4 to 6 weeks after infection and quickly reach a maximum. At the end of the acute process (after 5 - 6 months), their concentration drops.
Long-term registration of the presence of anti-HCV IgM indicates that hepatitis C has become chronic.
An increase in IgM levels during the chronic period indicates reactivation.
The level of IgM immunoglobulins makes it possible to assess the effectiveness of treatment.

Anti-HCV IgG test

IgG antibodies appear in the patient’s blood serum 11–12 weeks after infection. Peak concentrations are recorded at 5–6 months. Further, antibodies remain at a constant level throughout the entire duration of the disease in the acute period and the recovery period.

Test for total antibodies to hepatitis C virus

Total antibodies to the virus (anti-HCV total) are used to diagnose “fresh” cases of the disease. Total antibodies are antibodies to the nucleocapsid protein C - cor (anti-HCV IgG) and 7 non-structural enzyme proteins NS (anti-HCV NS IgG) - anti-HCV NS3, anti-HCV NS4 and anti-HCV NS5.

Total antibodies to the hepatitis C virus appear in the blood serum of the infected person 11 - 12 weeks after the onset of infection, reach a peak at 5 - 6 months and remain at a constant level throughout the duration of the disease in the acute period and for 5 - 9 years after the recovery period .

Each type of antibody has its own diagnostic value:

Anti HCV C (cor) are the main indicators of contact with hepatitis C viruses.
Anti HCV NS3 is one of the first to be detected in the process of seroconversion (production of antibodies in response to the presence of the virus), indicates the severity of the infectious process and indicates a high viral load. With their help, hepatitis C is detected in patients who do not suspect they have an infection. The prolonged presence of anti-HCV NS3 in the blood serum indicates a high risk of chronicity of the process.
Anti HCV NS4 indicates that hepatitis C has a long course. The level of antibody titers can be used to judge the degree of liver damage.
Anti HCV NS5 indicates the presence of viral RNA. Their detection in the acute period is a harbinger of chronicity of the process. High antibody titers during treatment indicate that the patient is not responding to treatment.
Anti HCV NS4 and anti HCV This type of antibody appears late in the development of hepatitis. Their decrease indicates the formation of remission of the infectious process. After treatment, titers of NS4 and NS5 antibodies decrease over 8 to 10 years. This type of antibody does not protect against re-infection.

Rice. 2. Macropreparation. Liver cirrhosis is a serious complication of viral hepatitis C.

Interpretation of the test for hepatitis C - anti-HCV

The absence of antibodies to the hepatitis C virus is designated by the term “Normal”. However, this does not always mean that a person does not have a disease. Thus, the absence of antibodies in the blood of an infected person is recorded before they appear in the blood - up to 6 months from the moment of infection (on average after 12 weeks). The period of absence of antibodies in the blood of an infected person is called the “serological window”. 3rd generation test systems (ELISA-3) have high specificity (up to 99.7%). About 0.3% is due to false positive results.

The presence of anti-HCV indicates current infection or past infection.

Detection of IgM antibodies and Core IgG antibodies, an increase in Core IgG antibody titers and (+) PCR results in the presence of clinical and laboratory signs of acute hepatitis indicate an acute period of the disease.
Detection of IgM antibodies, anti-HCV Core IgG, anti-HCV NS IgG and (+) PCR results in the presence of clinical and laboratory signs of the disease indicate reactivation of chronic hepatitis C.
The detection of anti-HCV Core IgG and anti-HCV NS IgG in the absence of clinical and laboratory signs of the disease and a negative PCR result indicates that the patient has chronic hepatitis in the latent phase.

Rice. 3. Macroscopic specimen of the liver. Primary liver cancer is a serious complication of hepatitis C.

PCR for hepatitis C

Polymerase chain reaction (PCR) is the “gold standard” for diagnosing viral hepatitis C. The high sensitivity of the test makes it possible to detect the genetic material of viruses (RNA), even if there are only a few of them in the test material. PCR is capable of detecting viral RNA long before the appearance of antibodies in the blood serum, but not earlier than from the 5th day from the moment of infection. In case of illness, PCR of viral RNAs is detected not only in blood serum, but also in liver biopsies.

The polymerase chain reaction allows you to determine the presence or absence of hepatitis C viruses in the blood and decide on the initiation of treatment. It is known that up to 30% of patients get rid of the infection on their own, since they have a strong immune system and do not need treatment.
Using PCR, the genotype of the virus is determined. Different genotypes respond differently to treatment.
PCR is used to monitor the effectiveness of treatment.
PCR is used in the absence of antibodies in the blood, but in the presence of strong suspicions of the disease (increased levels of alkaline phosphatase, total bilirubin, 2-fold excess of liver enzymes AST and ALT).
PCR testing for hepatitis C is used to monitor intrauterine transmission of hepatitis viruses.

Viral load in hepatitis C

Using PCR analysis, it is possible to determine not only the presence of RNA viruses in the blood - a qualitative analysis (detected/not detected), but also their quantity - the viral load (the number of units of viral RNA in 1 ml of blood). Quantitative PCR is used to monitor the effectiveness of treatment.

The methods used for PCR have different sensitivities. In the Russian Federation, according to the 2014 methodological recommendations, it is recommended to use methods with a sensitivity of 25 IU/ml or less. According to the 2015 recommendations of the European Association for the Study of the Liver, it is proposed to use methods for determining viral RNA with a sensitivity of 15 IU/ml or less.

Depending on the sensitivity of the test system, the patient receives one or another test result:

The minimum sensitivity of the COBAS AMPLICOR analyzer is 600 IU/ml (old generation analyzer).
The minimum sensitivity of the COBAS AMPLICOR HCV-TEST analyzer is 50 IU/ml, which is 100 copies in 1 ml.
The minimum sensitivity of the RealBest HCV RNA analyzer is 15 IU/ml, which is 38 copies in 1 ml (part of the group of modern test systems). The specificity of these analyzers is 100%. With their help, RNA of hepatitis C viruses of subtypes 1a and 1b, 2a, 2b, 2c and 2i, 3, 4, 5a and 6 are detected.

If there are RNA copies below the sensitivity threshold of this analyzer, the patient receives a “not detected” response.

Rice. 4. Example of PCR analysis (quantitative test). Determination of viral load.

Interpretation of PCR test results for hepatitis C

The absence of viral RNA indicates the absence of infection.
The absence of RNA in the analysis against the background of the presence of antibodies in the blood indicates the disappearance of the disease under the influence of treatment or self-healing.
In some cases, the virus is present in the blood, but at subthreshold levels, when its concentration is not detected by analyzers. Such patients remain dangerous in terms of infection.
Detection of viral RNA for 6 consecutive months in patients with acute hepatitis C indicates that the disease has become chronic.
A decrease in viral RNA in tests during treatment indicates the effectiveness of the therapy and vice versa.

Rice. 5. Macropreparation. Fatty hepatosis is one of the consequences of the disease.

Basic biochemical blood tests for hepatitis C

Biochemical blood tests help establish the functional state of many human organs and systems.

Blood test for liver enzymes ALT and AST

Liver enzymes are synthesized intracellularly. They take part in the synthesis of amino acids. A large number of them are found in the cells of the liver, heart, kidneys and skeletal muscles. When organs are damaged (violation of the integrity of cell membranes), enzymes enter the blood, where their levels increase. Increased levels of enzymes are recorded with damage (lysis, destruction) of liver cells, myocardial infarction and other diseases. The higher the level of transaminases in the blood serum, the more cells were destroyed. ALT predominates in liver cells, AST predominates in myocardial cells. When liver cells are destroyed, the ALT level increases 1.5 - 2 times. When myocardial cells are destroyed, the AST level increases 8-10 times.

When diagnosing chronic viral hepatitis, it is necessary to pay attention to the AST/ALT ratio (de Ritis coefficient). An excess of AST levels over ALT indicates damage to liver cells.

The AST norm for men is up to 41 units/l, for women - up to 35 units/l, for children over 12 years old - up to 45 units/l.
The ALT norm for men is up to 45 units/l, for women - up to 34 units/l, for children 12 years of age and older - up to 39 units/l.
Normally (in healthy people), the AST/ALT ratio ranges from 0.91 to 1.75.

Blood test for bilirubin

Bilirubin is a breakdown product of hemoglobin. Bilirubin in the blood is contained in the form of indirect (up to 96%) and direct (4%). The process of decomposition of this substance occurs mainly in the liver cells, from where it is excreted from the body with bile. When liver cells are destroyed, the level of bilirubin in the blood serum increases. Normally, the content of total bilirubin is less than 3.4 - 21.0 µmol/l. At a level of 30 - 35 µmol/l and above, bilirubin penetrates the tissues, causing the skin and sclera to become jaundiced.

Rice. 6. Jaundice is one of the signs of liver damage.