Safety of Anti-tumor necrosis factor ( Anti-TNF) therapy in patients with chronic Hepatitis B

Abstract

The anti-tumor necrosis factor (TNF) agents are a class of medications which have given clinicians a new level of control over inflammatory illnesses that was previously unattainable with older disease modifying agents. Though each medication has unique molecular differences, they all have as their specific target the proinflammatory cytokine TNF-α. With the great improvements provided by the anti-TNF agents though has come a new spectrum of side effects. On the basis of the importance of TNF-α in granuloma formation, neutralization of TNF-α has led to reactivation of latent infections, the most notable being Mycobacterium tuberculosis. Another infectious agent that can elude eradication and enter a latent state, reactivating when the immune system is depressed, is the hepatitis B virus (HBV). Inhibition of TNF-α could also lead to immune suppression and reactivation of the virus much like that experienced with the reactivation of TB. The purpose of this article is to review the current medical literature for cases where anti-TNF agents were used to treat an inflammatory illness such as rheumatoid arthritis or Crohn's disease in patients chronically infected with HBV. Additionally, the role of TNF-α in HBV infection is explored, the differences in the anti-TNF agents are examined, and guidelines regarding the screening for and prophylaxis of HBV are discussed.