National Hepatitis B Month

According to the World Health Organization (WHO), there is an estimated 257 million people worldwide living with chronic hepatitis B virus (HBV) infection. In the United States, there are 2.2 million people chronically infected, the vast majority of whom are Asians.[1]^-[2] Chronic hepatitis B (CHB) is among the leading causes of liver disease, cirrhosis and hepatocellular carcinoma. There are over 750,000 deaths annually worldwide from HBV-related complications.¹

Histologic disease by liver biopsy with normal ALT patients: Current treatment guidelines for CHB base treatment recommendations on ALT levels, HBV DNA levels, and hepatic fibrosis stage.³ Usually, if a patient has normal ALT and low HBV DNA levels, they are considered to have inactive infection. However, if they have normal ALT and high HBV DNA levels, this can be confusing, which is why histological disease needs to be assessed. In 2009, SJGI conducted a retrospective study to determine how patients with normal ALT and high HBV DNA levels should be managed if histology was taken into consideration by liver biopsy. It was concluded that even with persistently normal ALT (≤ 30 IU/ml for men and ≤ 19 IU/ml for women) Asian CHB patients over the age of 35 who have high HBV DNA may have significant fibrosis on liver biopsy and need further evaluation.[3] A significant predictor of histological disease was older age.

Histologic disease by liver elastography with normal ALT patients: While liver biopsy is the gold standard for assessing the grade of inflammation and stage of fibrosis, it is an invasive procedure and has intrinsic risks and complications. Liver elastography is a noninvasive alternative tool for assessing liver fibrosis to guide treatment. SJGI conducted a study that included 136 Asian CHB adults with elevated HBV DNA and normal ALT. It was found that 28.1% had significant fibrosis based on elastography, while only 8.8% had significant fibrosis based on FibroTest (known as FibroSure in the U.S.). The study concluded that the use of serological markers alone doesn’t accurately assess fibrosis severity. They should be combined with other tests like elastography and imaging.[4]

Is Hepatitis B curable with current DAA treatment? Although current treatment allows for viral suppression, it is not a complete cure since HBV DNA can still be dormant in the liver cell nucleus and may reactivate. Most CHB patients who are on treatment will require long-term therapy, especially patients with cirrhosis. Current AASLD HBV antiviral therapy guidelines recommend that treatment can be stopped when the patient achieves an “immunological cure” with hepatitis B surface antigen (HBsAg) loss and sustained HBV DNA suppression.[5] The loss of HBsAg is strongly associated with good clinical outcome but is relatively rare. The estimated annual incidence of clearance of HBsAg without treatment is 1-2% in Asian and Western populations.[6]

In a retrospective study published by SJGI in the Journal of Viral Hepatitis in 2017 it was shown that the overall rate of HBsAg loss among 1072 CHB Asian adults on antiviral treatment was 4.58%, with no significant difference between HBeAg+/- patients. Of these patients, 33.3% had seroconversion to anti-HBs; 95.8% had undetectable HBV DNA; and 66% achieved ALT normalization.[7]

Physician Spotlight: Dr. Huy A. Nguyen

Dr. Huy A. Nguyen graduated with a BS degree in Biochemistry from the University of California, Davis, and received his medical degree from the University of Minnesota Medical School. After finishing his Internal Medicine residency training at Santa Clara Valley Medical Center, he completed his gastroenterology fellowship at the University of Minnesota Medical School with a defined interest in hepatitis C. He served as Associate Chief of Gastroenterology at Santa Clara Valley Medical Center for two years after completing his fellowship.

In 2009, Dr. Nguyen was recognized as a Fellow of the American Gastroenterological Association (AGAF), recognition by which the AGA honors superior professional achievement in clinical private or academic practice and in basic or clinical research.

As a board-certified gastroenterologist, his interests include inflammatory bowel disease, liver disease, liver cancer, and viral hepatitis B and C. He has published articles in many peer-reviewed journals. He is a senior staff physician at SJGI and is currently medical director of Montpelier Surgery Center (MSC).