Management of HBV infection during immunosuppressive treatment. Mediterr J Hematol Infect Dis. 2009;1:e2009025. [PMID: 21415959 PMCID: PMC3033125 DOI: 10.4084/mjhid.2009.025]

Infectious Complications of Biological and Small Molecule Targeted Immunomodulatory Therapies

The past 2 decades have seen a revolution in our approach to therapeutic immunosuppression. We have moved from relying on broadly active traditional medications, such as prednisolone or methotrexate, toward more specific agents that often target a single receptor, cytokine, or cell type, using monoclonal antibodies, fusion proteins, or targeted small molecules. This change has transformed the treatment of many conditions, including rheumatoid arthritis, cancers, asthma, and inflammatory bowel disease, but along with the benefits have come risks. Contrary to the hope that these more specific agents would have minimal and predictable infectious sequelae, infectious complications have emerged as a major stumbling block for many of these agents. Furthermore, the growing number and complexity of available biologic agents makes it difficult for clinicians to maintain current knowledge, and most review articles focus on a particular target disease or class of agent. In this article, we review the current state of knowledge about infectious complications of biologic and small molecule immunomodulatory agents, aiming to create a single resource relevant to a broad range of clinicians and researchers. For each of 19 classes of agent, we discuss the mechanism of action, the risk and types of infectious complications, and recommendations for prevention of infection.

Kidney Transplantation From Donors with Hepatitis B

The growing demand for organ donors to supply the increasing number of patients on kidney waiting lists has led most transplant centers to develop protocols that allow safe use of organs from donors with special clinical situations previously regarded as contraindications. Deceased donors with previous hepatitis B may be a safe resource to increase the donor pool even if there is still controversy among transplantation centers regarding the use of hepatitis B surface antigen-positive donors for renal transplantation. However, when allocated to serology-matched recipients, kidney transplantation from donors with hepatitis B may result in excellent short-term outcome. Many concerns may arise in the long-term outcome, and studies must address the evaluation of the progression of liver disease and the rate of reactivation of liver disease in the recipients. Accurate selection and matching of both donor and recipient and correct post-transplant management are needed to achieve satisfactory long-term outcomes.

Prevention of hepatitis B virus infection: from the past to the future

About 3-5 % of the world's population is chronically infected by hepatitis B virus (HBV) and is at risk of developing liver cirrhosis or hepatocellular carcinoma. The risk of dying prematurely because of chronic HBV infection is higher in younger people. The current strategies to prevent HBV infection involve immunization (active and/or passive) and antiviral chemoprophylaxis. The vaccines available for active immunization, containing hepatitis B surface antigen, are safe and confer long-term immunity in most healthy subjects. Since the vaccination is unsatisfactory in some patients, e.g., those with chronic kidney disease, human immunodeficiency virus infection, type I diabetes mellitus, and celiac disease, new strategies of vaccination are required. The neonatal, infant, and adolescent routine program vaccination in about 180 countries has greatly decreased the disease burden. Passive immunization with specific HBV immunoglobulins is recommended after single acute exposure, in infants born to infected mothers, and in HBV-infected patients undergoing liver transplantation combined with nucleoside/nucleotide analogues (chemoprophylaxis). Chemoprophylaxis is also indicated in HBV carrier candidates for immunosuppressive treatment and in patients with occult B infection undergoing immunosuppressive therapy or hematopoietic stem cell transplantation. Since HBV is not eradicable by an immune response or by antiviral drugs developed so far, the only preventive strategy remains global neonatal vaccination in all countries, firstly in HBV-endemic countries.

Patients with hematological malignancies and serological signs of prior resolved hepatitis B

Hepatitis B virus (HBV) infection affects a large part of the world population. Within the different virological HBV categories that have been identified, patients with occult HBV infection represent a peculiar group. These individuals harbor a replication competent virus, inhibited in its replicative function. Accordingly, cases of reactivations have been observed in immunosuppressed individuals who lose immunological control over the infection. Patients with hematological malignancies (HM) are treated with intense myelo- and immunosuppressive chemotherapy regimens which favor HBV reactivation. This event can have severe consequences, such as hepatitis flare, hepatic failure and even death. In addition, it can lead to delays or interruptions of curative treatments, resulting in a decreased disease free and overall survival. In this review, we will examine the event of HBV reactivation in patients with signs of resolved HBV infection undergoing treatment for HM and propose possible management strategies.