PROGRESSIVE IMMUNODEFICIENCY AND FATAL PNEUMONITIS ASSOCIATED WITH HUMAN HERPESVIRUS-6 INFECTION IN AN INFANT

Human herpesvirus 6 (HHV-6), an important opportunistic pathogen in im munocompromised patients, causes fatal pneumonitis, encephalitis, and bone marrow suppression, Its ability to infect and destroy T lymphocyt es may allow it to synergize with the human immunodeficiency virus in the destruction of lymphoid tissues in patients with AIDS, We describe herein an infant who had an immunodeficiency associated with thymic a trophy and severe T lymphocytopenia who developed fatal pneumonitis du e to HHV-6, Dense and disseminated infection of T lymphocytes with HHV -6 was also documented, In the absence of any other documented cause o f immunodeficiency, we hypothesize that congenital infection of this i nfant with HHV-6 may have caused progressive destruction of her cellul ar immune system, leading to the fatal pneumonitis, Thus, HHV-6 infect ion may have been the cause of both her immunodeficiency and her fatal opportunistic infection.