It can be seen that the quantitative analysis of HBV DNA shows that the curative effect is only meaningful in theory. From the clinical practice, the quantification of hepatitis B virus is an unstable value, which changes at any time. The value may change when treated, and it will also change when not treated. This change may be therapeutic effect, natural change or test deviation. Judging from the actual situation of various medical institutions at present, the quantitative detection of DNA is still in the exploratory stage, various detection methods are not perfect, the quantitative standards are not uniform, and the obtained detection values swing from side to side with great deviation.
First of all, the methods used to detect HBV DNA quantification are not uniform. At present, the main detection methods used are: fluorescence quantitative PCR, competitive PCR, PCR enzyme-linked immunosorbent assay, fluorescence labeling method and PCR enzyme-linked chemiluminescence method. These methods not only have their own advantages and disadvantages, but also use reagents from different countries and regions and various instruments and equipment. The established standard curve is different from the standard fluorescence, and the normal values obtained are naturally different.
Second, there are too many factors affecting the quantitative accuracy, and the results are not stable, and the coefficient of variation can sometimes reach 30%. A very small amount of nucleic acid pollution may lead to the difference of test results. Therefore, at present, the reliability of DNA quantitative detection results is limited to some large hospitals with good experimental conditions, and it will take time to fully promote it.
Third, there is no unified national standard for HBV DNA quantification. It is difficult to unify the range of normal and abnormal values, and the detection data of various places and units are not comparable. The same serum will be tested in different hospitals, and its value will be different. Fourth, sampling error is inevitable. It is a common error that the experimental results differ by an order of magnitude (that is, 10 times). Fifthly, the polymerase chain reaction technology used to detect HBV DNA is extremely sensitive. In practice, a very small amount of nucleic acid pollution may produce false positive results.
Therefore, in the current situation, DNA testing can only be used as an auxiliary means, and exaggerating its function will not only mislead the treatment of diseases, but also cause unnecessary mental burden to patients. Therefore, to determine the severity of the patient's illness in clinic, we should not only observe and understand the specific symptoms of the patient, but also look at the results of other tests such as hepatitis B "two and a half" and liver function (DNA testing needs to obtain consistent results repeatedly before it can be used as a diagnostic basis). Only in this way can we accurately judge the severity of the patient's condition and the real effect of drug treatment. At present, both doctors and patients trust the clinical significance of DAN test value too much, and it is very unfavorable to treat hepatitis B to take the level and fluctuation of Dan test value as the standard of effective treatment.