Viruses and bone marrow failure.

Many agents are associated with bone marrow failure, including toxins, inherited metabolic defects, ionizing radiation, and viral infection. In most cases, the etiologic agent is unknown. Many of these unclassified cases have symptomatic, immunologic, or epidemiologic similarities to viral infections. Viruses from different taxonomic families have been implicated in bone marrow failure syndromes, and they appear to cause hematosuppression by a variety of mechanisms. Some of the viruses involved in relatively well characterized suppressive interactions will be reviewed, including parovovirus B19, dengue, hepatitis viruses, Epstein-Barr virus, cytomegalovirus and the human immunodeficiency virus.