HBSAg in serum

HBsAg in serum is normal.

Surface HA( HBsAg) detection of HBV in serum confirms acute or chronic infection with HBV virus.

In acute disease, HBsAg is detected in the blood serum in the last 1-2 weeks of the incubation period and in the first 2-3 weeks of the period of clinical manifestations. Circulation of HBsAg in the blood can be limited to a few days, so one should strive for an early primary

. Fig. Antigenic structure of HBV: 1 - outer shell - surface Ar( HBsAg);2 - nuclear Ar( HBcAg);3-Ar e( HBeAg);4 - DNA polymerase, hepatitis B virus DNA

Fig. Antigenic structure of HBV: 1 - outer shell - surface Ar( HBsAg);2 - nuclear Ar( HBcAg);3-Ar e( HBeAg);4 - DNA polymerase, hepatitis B virus DNA

examination of patients. The frequency of detection of HBsAg depends on the sensitivity of the test method used. The ELISA method allows to detect HBsAg in more than 90% of patients. In almost 5% of patients, the most sensitive methods of investigation do not show HBsAg, in such cases the aetiology of HBV is confirmed by the presence of anti-HBc IgM.The concentration of HBsAg in the blood serum with all forms of severity of HBV at the height of the disease has a significant range of oscillations, but there is a definite regularity: in an acute period there is an inverse relationship between the concentration of HBsAg in the serum and the severity of the disease. High concentration of HBsAg is more often observed in mild and moderate forms of the disease. In severe and malignant forms, the concentration of HBsAg in the blood is often low, and in 20% of patients with severe form and in 30% of malignant blood in the blood can not be detected. Appearance against this background in patients with AT to HBsAg is regarded as an unfavorable prognostic sign, it is determined in malignant forms( fulminant) of HBV.

In acute HBV, the concentration of HBsAg in the blood gradually decreases until this Ag disappears completely. HBsAg disappears in most patients within 3 months of the onset of acute infection. Reduction of HBsAg concentration by more than 50% by the end of the 3rd week of the acute period, as a rule, indicates a close end to the infectious process. Usually, in patients with a high concentration of HBsAg at the height of the disease, it is found in the blood for several months. In patients with a low concentration of HBsAg, it disappears much earlier( sometimes a few days after the onset of the disease).In general, the period of detection of HBsAg ranges from several days to 4-5 months. The maximum period of detection of HBsAg in the smooth course of acute HBV does not exceed 6 months from the onset of the disease.

HBsAg can be detected in practically healthy people, usually with preventive or accidental research. In such cases, other markers of HBV-anti-HBc IgM, anti-HBc anti-HBe, are studied to study the functional state of the liver. If the results are negative, repeated studies on HBsAg are necessary. If HBsAg is detected during repeated studies of blood for 3 months or more, this person is referred to the chronic carriers of surface Ag. Carrying HBsAg is a fairly common phenomenon. In the world there are more than 300 million carriers, in our country - about 10 million. The cessation of HBsAg circulation with subsequent seroconversion always indicates the sanation of the body.

The blood test for HBsAg is performed for the following purposes:

■ diagnosis of acute HBV:

□ incubation period;

□ acute period of the disease;

□ early stage of convalescence.

■ Diagnosis of chronic carriage of HBV virus;

■ with the following diseases:

□ persistent chronic hepatitis;

□ liver cirrhosis;

■ screening, identification of patients at risk:

□ patients with frequent blood transfusions;

□ patients with CRF;

□ patients with multiple hemodialysis;

□ patients with immunodeficient conditions, including those with HIV infection.