4. Acute Hepatitis B Infection
First, HBV DNA and DNA polymeraise appear in the blood stream, several weeks later HBcAg and HBeAg is detectable. HBsAg is then appears in the blood stream and 1 to 6 weeks symptoms may appear, HBcAb is the first detectable antibody to appear. In the majority of cases as the immune system continues it's fight HBeAg disappears from the blood stream and a few weeks later HBeAb's appear. The level of ALT in the blood then starts to fall and HBsAg disappears from serum at about the same time as HBsAb's are first detected.
An infected person may have zero, mild or severe symptoms that in some cases may prove fatal, in the elderly mortality rates can reach 10 to 15%.
When symptoms occur they normally begin with anorexia, malaise, nausea and vomiting and often fever. Distaste for cigarettes is common early sign. After around 3-10 days dark urine occurs and jaundice may follow. Other symptoms may include itching and pale stools. Symptoms then typically subside and the period of illness normally lasts between 4 to 8 weeks. Frequently an acute hepatitis B infection is misdiagnosed as 'flu' and an infected person may not realise that they have been exposed to the virus.
Some cases may develop into fulminant, fatal liver failure.
In most cases no special treatment is required for acute hepatitis B infection and most people can safely return to work when jaundice (if any) resolves and once they feel well enough even though ALT has not returned to normal levels. However alcohol should be avoided until the infection has resolved itself.
Once HBsAb's appear the infection is considered to have been successfully defeated and the person is considered immune from future hepatitis B infection.
Where symptoms are life threatening there is little that can be done although liver transplantation may be an option.
In the majority of cases prognosis is good and the individual will recover completely and be immune from subsequent hepatitis B infection. However around 10% of cases do not clear up completely and a chronic infection remains.
There are many factors that influence the probability of developing a chronic infection. Age is important and transmission from mother to infant at birth or infection while very young nearly always results in chronic infection (90%), In children the rate is lower (25%) and in healthy adults the risk of developing chronic infection is much reduced (2 - 5%). Other risk factors for developing chronic hepatitis include: being of the male gender; homosexual sexual orientation; having an altered immune system; there may also be genetic component with certain racial groups having a higher risk of cronicity but this has yet to be proved(?).
In up to 10% of people infected with hepatitis B the HBsAg persists and HBsAb do not appear. If this persists for 6 months or more after acute infection then the condition is termed chronic. Of the 10% who develop chronic HB most are asymptotic carriers of the of the virus.
People with HBsAg, HBeAg, No HBsAb, No HBeAb are generally termed as having Chronic Active HB and around 50% of chronic cases are of the active form.
People with HBsAg, No HBeAg or have HBeAb are generally termed as having Chronic Persistent HB or Sub Clinical Carriers. (I believe these are slightly different but have not found out exactly what the difference is.)
Most people with Chronic persistent hepatitis B are asymptotic carriers and do not develop liver severe liver problems and treatment with Interferon (IF) is not indicated. However caution must be taken to avoid transmitting the virus and you should be checked by your doctor periodically to monitor liver function etc.
Most people with chronic active hepatitis B are also asymptotic carriers but are at increased risk of severs liver problems, very infectious and treatment with IF (currently the only severe cure, (although others are being developed) is indicated.
Some people with chronic hepatitis B have "flare ups" where they have the symptoms of acute hepatitis.
At present the only treatment generally available in conventional medicine is interferon although several new drugs and treatments are being researched. Interferon and experimental drugs are covered in their own chapters.
At present a liver biopsy is the only way to firmly establish the exact extent of a hepatitis B infection and to assess any damage done to the liver. A biopsy is often required before starting and on completion of any treatment so the effectiveness of the treatment can be assessed.
Before treatment for chronic hepatitis B and to assess the progress of the disease it is generally recommended to have a liver biopsy as this is currently the only way to accurately assess the course of the disease and if the liver is found to have advanced cirrhosis or is decompensated then interferon or/and other treatments should be used with caution or not used.
Liver biopsy is a diagnostic procedure used to obtain a small amount of liver tissue, which can be examined under a microscope to help identify the cause or stage of liver disease.
The most common way a liver sample is obtained is by inserting a needle into the liver for a fraction of a second. This can be done in the hospital, and the patient may be sent home within 3-6 hours if there are no complications. The physician determines the best site, depth, and angle of the needle puncture by physical examination or ultrasound. The skin and area under the skin is anaesthetised, and a needle is passed quickly into and out of the liver. Approximately half of individuals have no pain afterwards, while another half will experience brief localised pain that may spread to the right shoulder.
Another technique used for liver biopsy is guiding the needle into the liver through the abdomen or chest using various imaging techniques. This approach is used when there are localised tumours identified by ultrasound or computed tomography (CT). Either ultrasound or CT scanning is used to pinpoint the site of the tumour and guide the needle to this specific area through the abdomen or chest. After this procedure, the patient is usually allowed to go home the same day.
Less commonly used biopsy techniques are laparoscopy, transvenous or transjugular liver biopsy, and surgical liver biopsy.
With laparoscopy, a lighted, narrow tubular instrument is inserted through a small incision in the abdominal wall. The internal organs are moved away from the abdominal wall by gas that is introduced into the abdomen. Instruments may be passed through this lighted instrument or through separate puncture sites to obtain tissue samples from several different areas of the liver. Patients who undergo this procedure may be discharged several hours later.
Transvenous or transjugular liver biopsy may be performed by a radiologist in special circumstances, e.g. when the patient has a significant problem with blood clotting (coagulopathy) or a large amount of fluid within the abdomen (ascites). With this procedure, a small tube is inserted into the internal jugular vein in the neck and radiologically guided into the hepatic vein, which drains the liver. A small biopsy needle is then inserted through the tube and directly into the liver to obtain a sample of tissue.
Finally, liver biopsy may be done at the time a patient undergoes an open abdominal operation, enabling the surgeon to inspect the liver and take one or more biopsy samples as needed.
Liver biopsy is often used to diagnose the cause of chronic liver disease that results in elevated liver tests or an enlarged liver. It is also used to diagnose liver tumours identified by imaging tests. In many cases the specific cause of the chronic liver disease is highly suspected on the basis of blood tests, but a liver biopsy is used to confirm the diagnosis as well as determine the amount of damage to the liver. Liver biopsy is also used after liver transplantation to determine the cause of elevated liver tests and determine if rejection is present.
The primary risk of liver biopsy is bleeding from the site of needle entry into the liver, although this occurs in less than 1% of patients. Other possible complications include the puncture of other organs, such as the kidney, lung or colon. Biopsy, by mistake, of the gallbladder rather than the liver may be associated with leakage of bile into the abdominal cavity, causing peritonitis. Fortunately, the risk of death from liver biopsy is extremely low, ranging from 0.1% to 0.01%.
The primary alternative to a liver biopsy is to make the diagnosis of a liver disease based on the physical examination of the patient, medical history, and blood testing. In some cases, blood testing is quite accurate in giving the doctor the information to diagnose chronic liver disease, while in other circumstances a liver biopsy is needed to assure an accurate diagnosis.
In most circumstances, a liver biopsy is only performed once to confirm a suspected diagnosis of chronic liver disease. Occasionally, liver biopsy is repeated if the clinical condition changes or to assess the results of medical therapy, such as drug treatment of chronic viral hepatitis with interferon or prednisone therapy of autoimmune hepatitis. Patients who have undergone liver transplantation often require numerous liver biopsies in the early weeks to months following the surgery to allow accurate diagnoses of whether the new liver is being rejected or whether other problems have developed.
After a few weeks they will have the result of your biopsy. Try to listen very carefully to what the doctor tells you, it may sound like gibberish but make notes then you can ask questions of your doctor, look things up in books, ask on the support group etc later when you've had a chance to digest things. Ask your doctor if you can have a copy of your biopsy results for reference. If the biopsy was for hepatitis B infection depending on the results of the biopsy they may suggest you take interferon.
This information is included to help assess the results of a liver biopsy.
Nomenclature, grading, staging of liver biopsies.
A recommendation to replace the old terminology for chronic active and chronic persistent hepatitis (Popper, 1971; Rev International Group, 1968) is now becoming widely accepted for a variety of reasons (Gerber, 1992; Ludwig, 1993; Scheuer, 1986).
The new nomenclature would use "chronic hepatitis" with the addition of a grading of activity of the hepatitis based on the degree of inflammation and necrosis and the stage of fibrosis. The terminology will also include the etiologic agent or cause, if known (International Working Party, 1994).
Several grading and staging systems have been proposed that use a variety of scores (Bedossa, et al, 1994; Desmet, 1994; Ishak, et al, 1995; Ludwig, 1993; Scheuer, 1991). Many of these systems have been modified from Knodell, 1981.
If your nervous about it ask your doctor for some valium or similar to take the night before and the morning before you go in (make sure the doctor doing the biopsy and the nurses looking after you knows if you've taken anything), also it's a good idea to have someone pick you up from the hospital.
The procedure is simple, you lie on your side and a local anaesthetic is administered. A needle is inserted between your ribs and a core of liver tissue is removed. This is normally painless however some people get a pain in the right shoulder. After the biopsy you must lie on your side for about 4 hours to help stop any bleeding and your blood pressure is taken, If you need pain killers ask for them. After this you can normally leave the hospital. When at home you should take it easy for the first week, generally sitting and sleeping to apply some pressure to the side with cushions or pillows as this aids healing, helps prevent bleeding and may be more comfortable. For 14 days after the biopsy you should remain within one hour of a major hospital and you should ensure the people with you know, or you should carry information to alert medical staff that you have recently had a biopsy.
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