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Blood test
Erythema multiforme, circular lesions - hands
Hepatitis B virus
 
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Hepatitis virus serology

Alternative names:

anti HCV test; anti-delta agent antibody; Australian antigen; HAA; HBsAg; hepatitis A & B panel; hepatitis A virus (HAV); hepatitis B surface antigen; hepatitis B virus (HBV); hepatitis C virus (HCV); hepatitis D - test; hepatitis-associated antigen; serial anti-HCV

How the test is performed:

Adult or child:
Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and a tourniquet (an elastic band) or blood pressure cuff is placed around the upper arm to apply pressure and restrict blood flow through the vein. This causes veins below the tourniquet to distend (fill with blood). A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the tourniquet is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

Infant or young child:
The area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. Cotton or a bandage may be applied to the puncture site if there is any continued bleeding.

How the test will feel:

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed:

This test is performed to detect hepatitis. Hepatitis is an inflammation of the liver caused by a virus. Three common hepatitis viruses are recognized: hepatitis A, hepatitis B, and hepatitis C (C is also called non-A, non-B).

Infection with hepatitis A virus (HAV) was originally called infectious hepatitis, but this terminology is inaccurate. HAV has a short incubation period of 2 to 6 weeks; it is excreted in the stool and transmitted via the fecal-oral route.

Infection with HBV was originally called serum hepatitis, but this terminology is no longer used. HBV has a long incubation period (that is, 5 weeks to 6 months). It is most frequently transmitted by blood transfusion, but can also be contracted through other body fluids. HBV may cause a severe and unrelenting form of hepatitis ending in liver failure and death. The incidence of HBV is increased among blood transfusion recipients, male homosexuals, dialysis patients, transplant patients, IV drug users, and individuals with leukemia or lymphoma.

The HBV, also called the Dane particle, is made up of an inner core surrounded by an outer capsule. The outer capsule contains the HBsAg (surface antigen). The inner core contains HBcAg (core antigen). HBeAg is also found within the core. The antibodies produced against these antigens are called HBsAb, HBcAb, and HBeAb.

Hepatitis C is transmitted in a manner similar to HBV. The incubation period is 2 to 12 weeks after exposure. The clinical manifestations of the illness parallel those of HBV. Most patients with hepatitis caused by blood transfusions have hepatitis C.


Adam

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