Human cytomegalovirus infection: new methods for virological diagnosis

Recently developed methods have greatly increased the sensitivity and speed of virological diagnosis of cytomegalovirus infection. Virus can be detected in infected cell cultures within 24 or 48 hours of specimen inoculation by using monoclonal antibodies to immediate-early antigens in immunocytochemistry procedures or DNA sequences in hybridisation in situ assays. CMV antigens can also be detected directly in infected cells within clinical specimens. An early antigen can be visualized in nuclei of circulating leukocytes from viremic patients. DNA hybridization is used for CMV analysis in Dot-blot, Southern-blot and in situ hybridization assays. DNA amplification, by polymerase chain reaction (PCR), has proven to be a very sensitive method for diagnosis of CMV infection and should be useful for investigation of CMV pathogenesis and latency. Serologic assays such as ELISA and latex agglutination assays are accurate for screening donors and recipients of blood and organ or marrow graft. Studies of viral protein epitopes recognized by human sera are in progress.