Hepatitis B affects an estimated 350 million people in the world. About one quarter will develop serious complications such as chronic hepatitis, cirrhosis complications (bleeding varices, ascites, liver failure) and liver cancer. In Asian countries, the virus is commonly transmitted from mother to child during childbirth. Once infected at birth, the virus persists for life in the liver. Fortunately, this can be effectively prevented by vaccinations, starting at birth.
During the life-time of a hepatitis B carrier, a complex and dynamic interaction of the body’s immune system with the virus occurs and the disease passes through several phases, which are usually silent. Regular blood tests and scans are needed for accurate monitoring. The tests may reveal significant liver inflammation that can lead to cirrhosis, if left untreated. Not all stages of the disease require treatment. The aims of a follow-up program are to identify the window of opportunity when treatment may be helpful and to screen for liver cancer. The aims of treatment are to delay, reduce or prevent the complications of cirrhosis and cancer. We hope to achieve immune control over the virus. If this fails, suppression of the virus may be needed. As new breakthroughs and medications become available, concepts and treatment strategies change. Currently, treatment is recommended in the “immune clearance” and “immune escape” phases of the illness, illustrated in the diagram below.
Two main types of treatment are available: the “injectable” and “oral” medications. “Injectable” treatments work by boosting the immune system to help control viral activity while “oral” treatments directly suppress virus activity. Decision-making on treatment can be complex as many factors are considered. Whenever possible and appropriate, a fixed duration of treatment is always preferred to long term suppressive treatment. Some of the factors to be considered include: age, gender, plans for pregnancy, family history of liver cancer, liver function, presence of cirrhosis, phase of disease, virus DNA level, risk of viral resistance, side-effects, costs and patient preference.
In summary, chronic hepatitis B is a disease with potentially serious complications. The aims of treatment are to delay, reduce or prevent the complications of cirrhosis and cancer. Regular monitoring is required to detect silent inflammation that is the window of opportunity when treatment can help.
About the author. Dr Yap Chin Kong, is a leading Specialist and Senior Consultant in Gastroenterology, Liver Diseases and Endoscopy. He was awarded a Merit Scholarship to study Medicine at the National University of Singapore and graduated with a Bachelor of Medicine & Bachelor of Surgery degree in 1983. In 1988 he obtained his Masters degree in Medicine (Singapore) and became a Member of the Royal College of Physicians (United Kingdom). He became a Fellow of the Academy of Medicine (Singapore) in 1994 and a Fellow of the Royal College of Physicians (Edinburgh) in 2000. In 1992, he was awarded the Health Manpower Development Program Award by the Ministry of Health to pursue advanced training in therapeutic ERCP (Endoscopic Retrograde Cholangio-Pancreatography) at the Academic Medical Centre in Amsterdam, The Netherlands. After a year of extensive experience he returned in 1993 to develop endoscopy further at the Singapore General Hospital until he left for private practice in 2004. He pioneered the use of endoscopic ltrasonography at SGH for a decade. During this time, he taught many generations of medical students and post-graduate doctors. In 2002, he continued to pursue his interest in early cancers of the stomach and colon and visited the Showa University Hospital in Yokohama, and the National Cancer Centre in Tsukiji, Tokyo. He lectured and taught at workshops locally and internationally, combining the best of Western and Eastern techniques. A Master endoscopist, he developed an innovative cap-fitted gastroscopy technique that is used to help countless patients worldwide. He was President of the Gastroenterological Society of Singapore (1999 to 2003) and was President of the Asia-Pacific Digestive Week in 2003. He is currently in private practice at Mount Elizabeth Medical Centre. His broad specialist experience include advanced endoscopy techniques such as ERCP treatment of bile duct stones and pancreas diseases, endoscopic ultrasound, treatment of esophagus, stomach, colon and liver cancers, viral hepatitis and inflammatory bowel disease. He is Visiting Consultant to the National University Hospital and Kandang Kerbau Womens’ & Childrens’ Hospital where he supervises gastroenterologists-in-training and performs endoscopy for sick children.