Pharmacotherapy/Treatment Of Hepatitis B And Hepatitis C Virus

Healthy liver

Hepatitis is an inflammation of the liver. It is caused by five types of viruses. They are hepatitis A, B, C ,D and E. The virus itself does not destroy the liver. The destruction comes from the body's immune response to fight the virus.

Hepatitis B (HB)

Hepatitis B is caused by hepatitis virus (HBV). They are deoxyribonucleic acid (DNA) viruses from the family of hepadnaviridae. Estimates have it that more than 2 billion people currently living either have it in the past or current do. About 7.4 percent of the world population have been infected and one percent of them are living with HIV.

There is no cure for HBV. It is highly contagious. It is contracted through contact with infected blood or body fluid. Mode of transmission is very similar to that of human immunodeficiency virus (HIV).

HBV is prevalent in the western Pacific (6.2 percent) and African region (6.1 percent). Other parts of the world carry a minor burden.

It affects children and adults alike. But the disease is more common in children (95 percent) than adults (5 percent). About 35-50 percent of children less than 6 who had it developed chronic symptoms. The situation is worse for infants less than one year as 80-90 percent develop chronic symptoms. Adults have a better chance of fighting the disease as statistics show that only 5 percent of infected persons get to chronic stage. About 20-30 percent of those who enter chronic stages develop liver cirrhosis or cancer. Adults develop immunity if they are able to clear it from their system unlike children that will likely live with it for life.

Read Also: All about hepatitis infection

The virus can survive outside the body for seven days. Incubation period is between 30-180 days. The virus can be detected after 30-60 days from the day of infection. Progression spans across several years or decades.

Symptoms

1. Jaundice

2. Dark urine

3. Extreme fatigue

4. Nausea and vomiting

5. Abdominal pain

6. Acute liver failure

7. Cirrhosis

8. Liver cancer

9. Joint pain

10. Loss of appetite

Liver failure can lead to poor absorption of nutrients in the body which can cause other symptoms. Failure of the liver to absorb vitamin D leads to thinning of the bones (osteoporosis) and vitamin A leads to loss of night vision including infection.

Mode Of Transmission

The virus is present in the blood. The major people at risk of infection are drug addicts who share needles. Anything that can lead to introduction of infected blood into the bloodstream. Also, mother to child transmission is possible. It does not happen during pregnancy. It can happen during delivery. Sex is one of the minor ways of contracting HBV. Blood transfusion and organ donation are also implicated.

Just as in HIV, HBV cannot be contracted by kissing or merely living in the same apartment. It is not contracted through eating foods contaminated with the virus.

Diagnosis

There are different ways to determine if somebody has HBV or not. They are:

1. Blood test: two markers can be used to detect the presence of HB in the body. They are the core and surface antigen. Surface antigen (HBsAg) appears within 1-10 weeks after infection. Presence of which is an indication of HB infection. Also, immunoglobulin M (IgM) antibody to the core antigen HBcAg is another indicator.

During initial infection, patients are also seropositive for hepatitis B e-antigen (HBe-Ag). It shows that the virus is highly replicating. It is termed chronic infection if HBsAg is present in the blood for more than six months.

There are also serologic blood markers that can help to identify the stage of infection (past and present) and also help predict people who are at high risk of complications. They are alanine aminotransferase/aspartate aminotransferase levels, alkaline phosphatase levels, gamma-glutamyl transpeptidase levels, total bilirubin and albumin levels. Others are hematologic and coagulation studies (platelets count, complete blood count, international normalised level, ammonia levels, erythrocytes sedimentation rate and sodium levels). For example, in hepatitis B patients, sodium level is low and protein level is high.

2. Ultrasound: another method of checking for infection is to study the liver. Sound waves are sent to the liver and the degree the sound is scattered is used as a method to determine the degree of damage done to the liver. Hepatitis is not the only thing that can cause liver damage.

3. Biopsy: this is another method to determine if the liver is doing fine. An incision is made in the liver and a small sample taken for analysis. Presence of the virus in the liver is an indication of the virus. Biopsy can be done more to determine the extent of damage.

4. CT scan and MRI

5. Percutaneous or laparoscopic

Pharmacotherapy/Treatment

Unfortunately, there is no cure for acute hepatitis B. There is only prophylaxis which is the use of immunoglobulin, entecavir and tenofovir oral daily. Immunoglobulin must be used within a space of 12 hours if it must work while entecavir and tenofovir can be given within 24 hours. Pregnant women confirm to be hepatitis B positive using DNA assay should be given antiviral prophylaxis.

Immunoglobulin is a compound found in the body that fights infection. But it was found to be effective in fighting HBV. It does this by increasing the body's immune response.

Acute hepatitis B can be managed with food and diet. Also, paracetamol, prednisolone, methotrexate, cyclophosphamide, drugs used to stop vomiting and alcohol should be avoided.

Chronic hepatitis B can be treated with antiviral drugs. Only 10-40 percent will require treatment as some clear it off their system without it. Treatment suppresses viral replication in about 50-90 percent of patients with chronic hepatitis B. It slows the progression of cirrhosis, cancer and improves survival while reducing inflammation of the liver.

Antiviral agents used for hepatitis B include lamivudine, adefovir and telbivudine. Lamividine works for some few months after which there is likely going to be resistance. Other antiviral drugs can be added. Combination of two or three is recommended but it is wrong to be changing drugs because of resistance. Doing so can cause all the drugs to be resistant.

Last option is liver transplant which is done when the liver fails. Immunoglobulin or prophylaxis is given after transplant to prevent the HBV in the blood to infect the new liver. Transplant can be from a deceased or living donor after screening.

It is possible to get reinfected. Relapse after treatment is possible.

Prevention is with the use of vaccines. Vaccines are safe. Vaccine can be given at birth to the baby to prevent mother to child transmission. 2 or 3 more doses can be given at a four weeks interval to the baby. Vaccines last for about 20-30 years. It is very effective as it has resulted in 95-100 percent immunity. Vaccine is recommended for people who are still young, in endemic areas, blood transfusion or organ donor. Those who use drugs, health workers, people in prison and such kind of location and those with multiple sex partners not using protection need it.

There are two types of vaccines. The first is the interferon alfa-2b (intron A). This vaccine is used for young people with HBV who want to avoid long term treatment or women who wish to get pregnant within the next few years. However, interferon alfa-2b must be avoided in pregnancy.

The second vaccine is pegylated interferon Alfa-2b. It works similar to the first with similar contraindications but with a better safety profile. It is given one dose weekly for 48 weeks. Both can be taken for up to six months. Side effects of both include nausea, vomiting, difficulty breathing, depression and lower white blood cells.

Only a few people will be able to clear the virus from their system. Treatment with nucleotide reverse transcriptase inhibitors in people with HBeAg for six months after HBeAg disappear from the blood and replaced by antibodies. In people without HBeAg the endpoint is not clear when to stop treatment. Different treatment guidelines have been postulated by different groups. HBeAg is associated with increased risk of progression of liver disease and it's complications. HBV patients are encouraged to control fluid intake.

Hepatitis C Virus (HCV)

Hepatitis C is the major cause of liver cancer. Acute hepatitis C can lead to chronic hepatitis C with different severity. It can last between a few weeks to a lifelong infection. There are many strains and subtypes of hepatitis C virus.

About 71 million people are living with chronic hepatitis C why 399000 people died in 2016 from the disease. About 15-45 percent of infected persons get it cleared from their system. 55-85 percent develop chronic hepatitis C infection. Out of these, between 15 and 30 percent develop liver cirrhosis within 20 years.

The disease is more prevalent in certain places like eastern Mediterranean (2.3 percent) and European regions (1.5 percent).

There are drugs suitable for hepatitis C infection. Majority of infection cases are as a result of sharing of injection by drug addicts.

Incubation period is 2 weeks to 6 months. About 80 percent of infected persons show no symptoms. 2.3-3.7 million HIV patients have past or present hepatitis C infection.

Symptoms

1. Fever

2. Fatigue

3. Loss of appetite

4. Nausea and vomiting

5. Abdominal pain due to fluid build up

6. Dark urine

7. Grey coloured faeces

8. Joint pain

9. Jaundice

10. Bleeding easily

11. Bruising easily

12. Itchy skin

13. Swelling of leg

14. Weight loss

15. Confusion

16. Drowsiness

17. Slurred speech

18. Spider like blood vessels in the skin

19. Cirrhosis

20. Liver cancer

Mode of transmission

It is contracted through infected blood. The virus is present in the blood. The major people at risk of infection are drug addicts who share needles. Anything that can lead to introduction of infected blood into the bloodstream. Also, mother to child transmission is possible. It does not happen during pregnancy. It can happen during delivery. Sex is one of the minor ways of contracting HBV. Blood transfusion and organ donation are also implicated.

Just as in HIV, HCV cannot be contracted by kissing or merely living in the same apartment. It is not contracted through eating foods contaminated with the virus.

Diagnosis

1. Nucleic acid test: this test is used to detect the presence of HCV ribonucleic acid to confirm chronic condition. It is sensitive after 1-2 weeks infection

2. Anti HCV antibodies with serologic test are sensitive after 12 weeks of infection but the test result can be gotten after some few days to a week.

3. Biopsy to determine the degree of liver damage

4. Magnetic resonance elastography (MRI) uses ultrasound and MRI to understand the situation of the liver.

5. Transient elastography sends vibration into the liver and uses the speed of dispersal through the liver to estimate liver stiffness.

6. Liver function tests check for leaking enzymes from the liver which rises after 7-8 weeks of infection.

Pharmacotherapy/Treatment

If you have acute hepatitis C, there is no recommended treatment. If your hepatitis C turns into a chronic hepatitis C infection, there are several medications available:

Read Also: Pharmacotherapy and treatment of Lassa fever

Interferon, peginterferon, and ribavirin used to be the main treatments for hepatitis C. They can have side effects like fatigue, flu-like symptoms, anemia, skin rash, mild anxiety, depression, nausea, and diarrhea.

But hepatitis C treatments have changed a lot in recent years. Now you’re more likely to get one of these medications called pan-genotypic direct-act8ng antiviral (DAAs):

1. Daclatasvir (Daklinza): You’ll take this pill once a day along with sofosbuvir for 12 weeks.

2. Sofosbuvir-velpatasvir: This daily pill, which you take for 12 weeks, should cure your disease.

3. Ledipasvir-sofosbuvir: This once-daily pill cures the disease in most people in 8-12 weeks.

4. Glecaprevir and pibrentasvir: This daily pill offers a shorter treatment cycle of 8 weeks for adult patients with all types of HCV who don’t have cirrhosis and who haven’t already been treated. The treatment is longer for those who are in a different disease stage. The prescribed dosage for this medicine is 3 tablets daily.

5. Ribavirin (Copegus, Moderiba, Rebetol, Ribasphere, Virazole): This comes as a tablet, capsule, or liquid. You take it with food twice a day, in the morning and evening, for 24 to 48 weeks or longer.

6. Sofosbuvir  with interferon and ribavirin: Take this tablet at the same time every day with food. You have to take it along with ribavirin and/or interferon, and you’ll probably be on it for 12 to 24 weeks.

7. Ombitasvir-paritaprevir- ritonavir:  You’ll take this tablet by mouth, possibly along with ribavirin.

8. Ombitasvir-paritaprevir-dasabuvir-ritonavir: This treatment is a combo of pills: two that you'll take once a day, and one you'll take twice with meals. You’ll take it for 12 to 24 weeks.

9. Sofosbuvir-velpatasvir-voxilaprevir: This combination is approved to treat adults with chronic HCV, either with no cirrhosis or with compensated cirrhosis (the stage of the disease that doesn't have symptoms), who’ve already had certain treatments.

10. Elbasvir-grazoprevir: This once-daily pill has cured the disease in as many as 97% of those treated.

There is no vaccine against hepatitis C infection. The only prevention is avoid risky behaviours that exposes one to the infection such as safe sex, avoid sharing sharp objects, etc.

Acute infection response to treatment. About 15-25 percent of infections get cleared even without treatment.