Hepatitis D virus, RNA determination, quantitative test (HDV-RNA, quantitative, 40 IU/ml)
Hepatitis C virus (HCV) is an RNA-containing virus with a virion size of 30-60 nm. It is mainly transmitted parenterally (through infected blood and its components). Infection is possible during parenteral manipulations, including in medical institutions, dental services, through injecting equipment, acupuncture, piercing, tattooing, and a number of services in hairdressing salons. The main feature of hepatitis C virus is its genetic variability, expressed ability to mutations. There are 6 main genotypes of hepatitis C virus. However, due to the mutational activity of the virus, about four dozen HCV subtypes can be present in the human body within one genotype. Genotypes 1b, 2 and 3 are predominantly prevalent on the territory of the Republic of Kazakhstan. This is one of the important factors determining the persistence of the virus and the high frequency of chronic hepatitis C.
The human immune system is simply unable to control the production of the necessary antibodies. While antibodies are produced for some viruses, their descendants with different antigenic properties are already formed.
To make a diagnosis, a comprehensive approach is used, and the laboratory tests play the key role in it.
The first test that is usually recommended is the determination of antibodies to the hepatitis C virus (anti-HCV). This test only establishes current or past infection. In addition, this test can give false positives (the test is positive, but there is actually no infection) and false negatives (the test is negative, but there is actually infection), for various reasons.
Therefore, to accurately diagnose hepatitis C, a more sophisticated examination is performed to determine the presence of HCV RNA in the blood. Currently, qualitative detection of HCV RNA by highly sensitive real-time PCR diagnostics with a lower limit of 15 IU/mL using automated closed-loop systems is used for this purpose. In comparison, previously used analyzers had a sensitivity threshold of 300 IU/ml. Thus, it confirms both the presence of infection and the fact of viral replication (multiplication) in the body. The number of viruses in the blood (viral load) allows to judge the activity or rate of viral multiplication.
The higher the viral load, the more active the viral replication. A high viral load is a factor that impairs the effectiveness of antiviral therapy. The lower the viral load, the higher the chances of successful cure.
In addition, if the viral content is high, the patient is more likely to infect others (sexual partners, family members).
In general, virologic diagnosis is based on the following principles:
?1. Determination of anti-HCV is the first line of HCV diagnosis (recommendation A1).
?2. In cases of suspected acute HCV or in immunosuppressed patients, HCV RNA should be determined (recommendation A1).
?3.If the anti-HCV test is positive, HCV RNA should be determined by a sensitive molecular method (recommendation A1).
?4. Patients with a positive anti-HCV test and a negative HCV RNA molecular test should be tested for HCV RNA after 3 months to confirm virus elimination (recommendation A1).
*“Clinical protocol for diagnosis and treatment of chronic hepatitis C in adults” A.V. Nersesov, K.S. Kaliaskarova, A.Ye. Dzhumabayeva, “Man and Medicine” magazine, Almaty, Kazakhstan No. 6 (37) p.2-20, 2014.
New opportunities in the diagnosis of hepatitis C