Hepatitis B – Diagnosis, Symptoms, and Treatment

What is Hepatitis B?

Hepatitis B is a virus that infects the liver and can result in both acute and chronic diseases. The virus that causes hepatitis B can be transmitted through blood and bodily fluids. It is most commonly being spread from mother to child at the time of birth, through sexual contact, IV drug use, and accidental needle sticks. Individuals with acute infection may have a fever, abdominal discomfort, malaise, nausea, vomiting, and jaundice. Patients with chronic infection often develop severe damage to the liver, known as cirrhosis, and have features of chronic liver disease such as ascites, esophageal varices, upper gastrointestinal bleeding, and confusion (hepatic encephalopathy).

Chronic infection associated with cirrhosis has a poor prognosis. Patients with hepatitis B and cirrhosis are at increased risk of developing liver cancer (hepatocellular carcinoma) and have a high rate of mortality.

What Causes Hepatitis B?

Hepatitis B is the name of a virus that infects the liver resulting in acute and injury and inflammation. This virus is also capable of avoiding the body’s immune system, becoming a chronic infection that leads to ongoing damage.  If untreated this can lead to scarring of the liver (cirrhosis) and progressive liver failure. Rarely, patients may develop liver failure during the acute infection. Hepatitis B is transmitted through the blood or sexual contact. Pregnant women may pass the infection to their child during pregnancy. Unprotected sex and injection drug use are common routes of infection.

How Common is Hepatitis B?

About 2 billion people in the world have had or currently have a hepatitis B infection. Worldwide, approximately 250 million people carry the virus. The virus is responsible for about 600,000 deaths each year related to liver disease. Rates of infection-related complications such as cancer and death have also doubled in the past 10 years. Healthy individuals have a less than 5% chance of progressing to chronic hepatitis B. These people also have a less than 1% chance of developing liver failure.

Infections with Hepatitis B are rarer in the United States due to vaccination. Healthcare workers are routinely vaccinated against this condition due to the risk of needle-stick injuries. Vaccination may also be recommended for those with a history of IV drug use. 

Signs and Symptoms

Symptoms and signs depend on the time since infection and if a chronic infection is present. Acute hepatitis B is often asymptomatic but may produce the following features:

• Fever
• Abdominal discomfort
• Malaise
• Nausea & vomiting
• Jaundice

A small subset of patients may also progress to fulminant liver failure. This will present with the symptoms listed above in addition to changes in mental status. Patients may be unable to communicate, be excessively sleepy, and confused. 

Chronic hepatitis B infection is often asymptomatic for a significant period. In some patients this never results in any significant symptoms, others will gradually accumulate damage to the liver as a result of the virus and present with the signs and symptoms of cirrhosis 20 to 30 years later. The most common signs of cirrhosis are: 

• Jaundice
• Esophageal varices – upper gastrointestinal bleeding
• Ascites – accumulation of fluid within the abdomen
• SBP – spontaneous bacterial peritonitis
• Confusion – hepatic encephalopathy
• Lower extremity edema

Patients who progress to cirrhosis frequently develop liver cancer (hepatocellular carcinoma) or die as a complication of chronic liver disease.

Diagnosis

The diagnosis of acute hepatitis B is commonly missed, it may have no symptoms or extremely vague symptoms that appear similar to any other viral illness. If you have a history of unprotected sex, IV drug use, or work in a place where accidental needle sticks are common your physician may suspect this condition and recommend testing. 

Chronic hepatitis B is generally always considered when a patient presents with the signs and symptoms of liver failure. Testing for the hepatitis B virus is a routine part of the workout for liver failure. 

The assessment of liver failure or suspected acute hepatitis B will begin with a CMP (comprehensive metabolic panel) to evaluate your liver function. Specific liver tests typically include AST, ALT, alkaline phosphatase, bilirubin, and coagulation studies (PT/INR, PTT).

If these laboratory values are abnormal and you have evidence of liver disease, your doctor will typically confirm the diagnosis of acute infection with “viral serologies” with are designed to detect the proteins that the hepatitis B virus creates. These are the hepatitis B surface antigen (HBsAg) and IgM antibody to hepatitis B core antigen. The diagnosis of chronic HBV infection is based upon the persistence of HBsAg for more than six months. If you test positive, your doctor will also usually check a hepatitis B virus DNA level and a viral antigen level (HBeAg), which is a marker of viral infectivity. Viral DNA levels and HBeAg are typically evaluated in individuals that are being considered for antiviral therapy. 

If you have signs and symptoms of cirrhosis or liver failure your physician may obtain imaging of the liver with an abdominal ultrasound or CT scan. Your doctor may order an MRI of the abdomen if more detail about the structure of the liver is required. In some cases, your doctor may recommend a liver biopsy, this is more common if the cause of your liver failure is unclear. Patients with severe cirrhosis often receive routine upper endoscopies to screen for esophageal varices (dilated esophageal veins) that can bleed without warning and lead to severe blood loss.

Hepatitis B Medication and Treatment

The treatment of hepatitis B is focused on prevention. Immunization is the primary strategy that is used to prevent the spread of hepatitis B. There are several high-risk groups that are routinely immunized, the most common are: 

• Healthcare workers
• Persons with underlying liver disease
• Immunocompromised patients (e.g., HIV/AIDS)
• Patients receiving immunosuppressive therapy
• Neonates of HBsAg positive mothers
• Persons born in endemic areas
• Persons with multiple sexual partners
• Persons with a history of sexually transmitted infection
• Inmates of correctional facilities
• Persons with a history of injection drug use
• Dialysis patients
• Family members & sexual contacts of HBV-infected persons

Those who are already infected with the hepatitis B virus will receive far different treatments depending upon their severity of illness, the presence of liver cirrhosis, and viral DNA levels. The goals are to reduce viral DNA levels, decrease viral infectivity (measured with HBeAg testing), and eliminate HBsAg.

Patients with acute hepatitis B and severe liver function abnormalities typically receive treatment with a nucleoside/nucleotide analog which slows viral replication, the most common of these are:

• Vemlidy (tenofovir alafenamide)
• Baraclude (entecavir)

Patients with chronic hepatitis B may receive medications intended to reduce the risk of liver failure and cirrhosis. The nucleoside/nucleotide analogs Vemlidy (tenofovir alafenamide) and Baraclude (entecavir) are commonly used. But an additional medication ommonly used in chronic infection as well. Pegasys (pegylated interferon) is another medication that is used for the treatment of chronic inflammation. Special treatment considerations are typically made for patients with liver cirrhosis, abnormal kidney function, or those who are pregnant.

References:

1. Lok AS, McMahon BJ. Chronic hepatitis B: update 2009. Hepatology 2009; 50:661. - https://www.ncbi.nlm.nih.gov/pubmed/19714720
2. LeFevre ML, U.S. Preventive Services Task Force. Screening for hepatitis B virus infection in nonpregnant adolescents and adults: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 2014; 161:58. - https://www.ncbi.nlm.nih.gov/pubmed/24863637
3. Terrault NA, Bzowej NH, Chang KM, et al. AASLD guidelines for treatment of chronic hepatitis B. Hepatology 2016; 63:261. - https://www.aasld.org/sites/default/files/2019-06/Terrault_et_al-2016-Hepatology.pdf