[Diagnosis and treatment of hepatitis B].

Hepatitis B constitutes a serious public health problem. It has been estimated that 350 million people--approximately 5% of the world population--have been infected by this virus. Of the people infected, in 90% to 95% of them there will be a spontaneous resolution of the disease. In 5% to 10% of the cases, though, the infection will persist and a chronic hepatitis will develop that may evolve leading, in the end, to liver cirrhosis, liver failure and/or carcinoma of the liver. The diagnosis of the different stages of the disease (i.e., acute, chronic infection) is performed using modern serologic techniques. Physicians, more recently, are having access to a series of laboratory tests which permit them to evaluate the viral load, replication of the virus and to testing of the efficacy of new anti-viral drugs. For the treatment of chronic hepatitis B new agents have been tested and some are being used with different degrees of success, such as, alfa-interferon, lamivudine, famciclovir, and adefovir dipivoxil, among others. Active immunization, using modern recombinant vaccines, are lately, the most important instrument of control of the infection caused by the hepatitis B virus.