Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
Infection with hepatitis B is suspected when the medical history and the
physical examination reveal risk factors for the infection or symptoms and signs
that are suggestive of hepatitis B. Abnormalities in the liver tests (blood
tests) also can raise suspicion; however, abnormal liver tests can result from
many conditions that affect the liver. The diagnosis of hepatitis B can be made
only with specific hepatitis B virus blood tests. These tests are known as
hepatitis 'markers' or 'serology.'
Markers found in the blood can confirm hepatitis B infection and
differentiate acute from chronic infection. These markers are substances
produced by the hepatitis B virus (antigens) and antibodies produced by the
immune system to fight the virus. Hepatitis B virus has three antigens for which
there are commonly-used tests - the surface antigen (HBsAg), the core antigen
(HBcAg) and the e antigen (HBeAg).
HBsAg and anti-HBs
The presence of hepatitis B surface antigen (HBsAg) in the blood indicates
that the patient is currently infected with the virus. HBsAg appears an average
of four weeks after initial exposure to the virus. Individuals who recover from
acute hepatitis B infections clear the blood of HBsAg within approximately four
months after the onset of symptoms.
These individuals develop antibodies to HBsAg (anti-HBs). Anti-HBs provides
complete immunity to subsequent hepatitis B viral infection. Similarly, individuals who are successfully vaccinated against
hepatitis B produce anti-HBs in the blood.
Patients who fail to clear the virus during an acute episode develop chronic
hepatitis B. The diagnosis of chronic hepatitis B is made when the HBsAg is
present in the blood for at least six months. In chronic hepatitis B, HBsAg can
be detected for many years, and anti-HBs does not appear.
Anti-HBc
In acute hepatitis, a specific class of early antibodies (IgM) appears that
is directed against the hepatitis B core antigen (anti-HBc IgM). Later, another
class of antibody, anti-HBc IgG, develops and persists for life, regardless of
whether the individual recovers or develops chronic infection. Only anti-HBc IgM
can be used to diagnose an acute hepatitis B infection.
HBeAg, anti-HBe, and pre-core mutations
Hepatitis B e antigen (HBeAg) is present when the hepatitis B virus is
actively multiplying, whereas the production of the antibody, anti-HBe, (also
called HBeAg seroconversion) signifies a more inactive state of the virus and a
lower risk of transmission.
In some individuals infected with hepatitis B virus, the genetic material for
the virus has undergone a structural change, called a pre-core mutation. This
mutation results in an inability of the hepatitis B virus to produce HBeAg, even
though the virus is actively reproducing. This means that even though no HBeAg
is detected in the blood of people with the mutation, the hepatitis B virus is
still active in these persons and they can infect others.
Hepatitis B virus DNA
The best marker of hepatitis B
virus reproduction is the level of hepatitis B
virus DNA in the blood. Detection of hepatitis B virus DNA in a blood sample
signals that the virus is actively multiplying. In acute hepatitis, HBV DNA is
present soon after infection, but is eliminated over time in patients' who clear
the infection. In chronic hepatitis, levels of HBV DNA often continue to be
elevated for many years and then decrease as the immune system controls the
virus. HBV DNA levels are sometimes referred to as the 'viral load'.
How are the hepatitis B blood tests interpreted?
The following table gives the usual interpretation for sets of results from hepatitis B
blood (serological) tests.
Most Likely Status*
Tests
Results
Susceptible, not infected, not immune
HBsAg
anti-HBc
anti-HBs
negative
negative
negative
Immune due to natural infection
HBsAg
anti-HBc
anti-HBs
negative
positive
positive
Immune do to hepatitis B vaccination
HBsAg
anti-HBc
anti-HBS
negative
negative
positive
Acutely infected
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
positive
positive
positive
negative
Chronically infected
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
positive
positive
negative
negative
*Interpretation of the hepatitis B virus blood tests should always be made by
an experienced clinician with knowledge of the patient's medical history,
physical examination, and results of the standard liver blood tests.
Liver cancer is the fifth most common cancer in the world and the majority of patients with liver cancer will die within one year as a result. Patients with associated cirrhosis caused by chronic hepatitis B or C infections, alcohol, and hemochromatosis are at the greatest risk of developing liver cancer. Many patients with liver cancer do not develop symptoms until the advanced stages of the tumor which usually makes prognosis poor. The combination of an imaging study (ultrasound, CT, or MRI scans) and an elevated blood level of alpha-fetoprotein will most effectively diagnose liver cancer, while a liver biopsy can make a definitive diagnosis. Medical treatments, including chemotherapy, chemoembolization, ablation, and proton beam therapy, are not very effective. Surgical removal of the tumor or a liver transplant may be most effective in certain cases.
Cirrhosis of the liver refers to a disease in which normal liver cells are replaced by scar tissue caused by alcohol and viral hepatitis B and C. This disease leads to abnormalities in the liver's ability to handle toxins and blood flow, causing internal bleeding, kidney failure, mental confusion, coma, body fluid accumulation, and frequent infections. Symptoms include yellowing of the skin, itching, and fatigue.
Pancreatic cancer is a malignant tumor of the pancreas. Pancreatic cancer has been called a "silent" disease because early pancreatic cancer usually does not cause symptoms.
Liver disease can be cause by a variety of things including infection (hepatitis), diseases such as gallstones, high cholesterol or triglycerides, blood flow obstruction to the liver, and toxins (medications and chemicals). Symptoms of liver disease depends upon the cause; however, common symptoms may include nausea, vomiting, upper right abdominal pain, and jaundice. Treatment depends upon the cause of the liver disease.
Sexually transmitted diseases, or STDs,
are infections that are transmitted during any type of sexual exposure,
including intercourse (vaginal or anal), oral sex, and the sharing of sexual
devices, such as vibrators. Women can contract all of the STDs, but may have no symptoms, or have different symptoms than men do.
Hepatitis C is an inflammation of the liver due to the hepatitis C virus (HCV), which is usually spread by
blood transfusion, hemodialysis, and needle sticks, especially with intravenous
drug abuse. Chronic hepatitis C may be treated with interferon, usually in combination with anti-virals.
Jaundice is a yellowish staining of the skin and whites of the eyes (sclerae) with bilirubin, the pigment found in bile. Jaundice can be an indicator of liver or gallbladder disease, or it may result from the rupture of red blood cells (hemolysis).
Drug-induced liver diseases are diseases of the liver that are caused by physician-prescribed medications, OTC medications, vitamins, hormones, herbs, illicit (“recreational”) drugs, and environmental toxins. There are three types of liver toxicity; dose-dependent toxicity, idiosyncratic toxicity, and drug allergy. The types of liver disease drugs cause include: mild elevations of blood levels of liver enzymes, hepatitis, necrosis, cholestasis, steatosis, cirrhosis, mixed disease, fulminant hepatitis, and blood clots.
Ascites, the accumulation of fluid in the abdominal cavity is most commonly caused by cirrhosis of the liver. Some of the other causes of ascites include portal hypertension, congestive heart failure, blood clots, and pancreatitis. The most common symptoms include increased abdominal girth and size, abdominal bloating, and abdominal pain. Treatment depends on the cause of ascites.
Sexually transmitted diseases, or STDs, are infections that are transmitted during any
type of sexual exposure, including intercourse (vaginal or anal), oral sex, and
the sharing of sexual devices, such as vibrators. Although treatment exists for many STDs, others currently are
usually incurable, such as those caused by HIV, HPV, hepatitis B and C, and HHV-8.
Nonalcoholic fatty liver disease (NAFLD) refers to a wide spectrum of liver disease ranging from simple fatty liver (steatosis), to nonalcoholic steatohepatitis (NASH), to cirrhosis (irreversible, advanced scarring of the liver). All of the stages of NAFLD have in common the accumulation of fat (fatty infiltration) in the liver cells (hepatocytes).
Thrombocytopenia refers to a decreased number of platelets in the blood. There are many causes of thrombocytopenia such as decreased platelet production (viral infections for example rubella, mumps, chickenpox, hepatitis C, and HIV); increased platelet destruction or consumption (for example sulfonamide antibiotics, heparin, blood transfusions, and lupus); or increased splenic sequestration (enlarged spleen due to conditions for example liver disease, blood cancers, and more). Treatment of thrombocytopenia depends on the cause.
Vasculitis is a general term for a group of uncommon diseases which feature inflammation of the blood vessels. Each form of vasculitis has its own characteristic pattern of symptoms. The diagnosis of vasculitis is definitively established after a biopsy of involved tissue demonstrates the pattern of blood vessel inflammation. Treatment is directed toward decreasing the inflammation of the arteries and improving the function of affected organs.
Drug addiction is a chronic disease that causes drug-seeking behavior and drug use despite negative consequences to the user and those around him. Though the initial decision to use drugs is voluntary, changes in the brain caused by repeated drug abuse can affect a person's self-control and ability to make the right decisions and increase the urge to take drugs. Drug abuse and addiction are preventable.
Hepatitis is most often viral, due to infection with one of the hepatitis viruses (A, B, C, D, E, F (not confirmed), and G) or another virus (such as those that cause infectious mononucleosis, cytomegalovirus disease). The main nonviral causes of hepatitis are alcohol and drugs. Many patients infected with hepatitis A, B, and C have few or no symptoms of illness. For those who do develop symptoms of viral hepatitis, the most common are flu- like symptoms including: loss of appetite, nausea, vomiting, fever, weakness, tiredness, and aching in the abdomen. Treatment of viral hepatitis is dependant on the type of hepatitis.
Encephalopathy means brain disease, damage, or malfunction. Causes of encephalopathy are varied and numerous. The main symptom of encephalopathy is an altered mental state. Other symptoms include lethargy, dementia, seizures, tremors, and coma. Treatment of encephalopathy depends on the type of encephalopathy (anoxia, diabetic, Hashimoto's, hepatic, hyper - hypotensive, infectious, metabolic, infections, uremic, or Wernicke's) are examples of types of encephalopathy.
The liver is the largest solid organ in the body, and is actually an gland. The liver has a wide variety of critical functions such as manufacturing proteins and metabolizing fats and carbohydrates. The liver also eliminates harmful biochemical waste products from the body (alcohol, drugs, toxins). The liver secretes bile that aids in digestion. Examples of diseases of the liver include cirrhosis, hepatitis, cancer, and fatty liver. Symptoms of liver disease include bleeding, easy bruising, edema, fatigue, and jaundice.
Optic neuritis is inflammation of the optic nerve, the structure that connects the eye to the brain. The precise cause of optic neuritis is unknown, but it is thought to be a type of autoimmune disorder. Optic neuritis most commonly develops due to an autoimmune disorder that may be triggered by a viral infection.
Fatigue can be described in various ways. Sometimes fatigue is described as feeling a lack of energy and motivation (both mental and physical). The causes of fatigue are generally related to a variety of conditions or diseases for example, anemia, mono, medications, sleep problems, cancer, anxiety, heart disease, drug abuse, and more. Treatment of fatigue is generally directed toward the condition or disease that is causing the fatigue.
Travelers should prepare for their trip by visiting their physician to get the proper vaccinations and obtain the necessary medication if they have a medical condition or chronic disease. Diseases that travelers may pick up from contaminated water or food, insect or animal bites, or from other people include malaria, meningococcal meningitis, yellow fever, hepatitis A, typhoid fever, polio, and cholera.
Septic arthritis, or infectious arthritis, is infection of one or more joints by bacteria, viruses, or fungi. Symptoms and signs of septic arthritis include fever, joint pain, chills, swelling, redness, warmth, and stiffness. Treatment involves antibiotics and the drainage of the infected joint.
Anabolic steroids are synthetic substances that are related to testosterone and promote skeletal muscle growth and the development of male sexual characteristics in both men and women. In the 1930s, it was discovered that anabolic steroids could promote skeletal muscle growth in lab animals, which lead to anabolic steroid abuse by bodybuilders and weight lifters.
Digestion is the complex process of turning food you eat into the energy you need to survive. The digestive process also involves creating waste to be eliminated, and is made of a series of muscles that coordinate the movement of food.
Hemophilia is one of a group of inherited bleeding disorders. Hemophilia A and B are inherited in an X-linked recessive genetic pattern and is more common in males. Symptoms of hemophilia include bleeding into the joints, muscles, GI or urinary tract, or brain or skull. Treatments for hemophilia is generally replacement of blood clotting factors.
Hepatitis means inflammation of the liver. Hepatitis A is one type of liver disease caused by a virus. Since hepatitis A is a virus, it can pass from person to person from eating or drinking contaminated food or coming into contact with contaminated materials containing the virus. Symptoms of hepatitis A include stomach pain, diarrhea, dark yellow urine, jaundice, and more. There is a vaccine to prevent contracting hepatitis A.
Polyarteritis nodosa is a rare autoimmune disease characterized by spontaneous inflammation of the arteries of the body. The most common areas of involvement include the muscles, joints, intestines (bowels), nerves, kidneys, and skin. Poor function or pain in any of these organs can be a symptom. Polyarteritis nodosa is most common in middle age persons. Polyarteritis is a serious illness that can be fatal. Treatment is focused on decreasing the inflammation of the arteries by suppressing the immune system.
Hepatitis A and hepatitis B are the two most commnon viruses that infect the liver. Hepatitis A and Hepatitis B can be prevented and treated with immunizations (vaccinations) such as Havrix, Vaqta, Twinrix, Comvax, Pediarix, and hepatitis b immune globulin (HBIG).
When you are pregnant, many sexually transmitted diseases (STDs) can be especially harmful to you and your baby. These STDs include herpes, HIV/AIDS, genital warts (HPV), hepatitis B, chlamydia, syphilis, gonorrhea, and trichomoniasis. Symptoms include bumps, sores, warts, swelling, itching, or redness in the genital region. Treatment of STDs while pregnant depends on how far along you are in the pregnancy and the progression of the infection.