CMV disease will be defined as CMV infection and syndrome with any of the following: evidence of host cellular viral inclusions on biopsy or body fluid for cytology, a positive conventional viral culture for CMV, a positive “rapid antigen” test for the presence of pp65 antigen on the cell surface of buffy coat leukocytes, or the qualitative presence of CMV DNA as analyzed by PCR amplified virus. Specimens used for the above diagnostic procedures may include blood, liver or lung biopsy, endoscopic mucosal biopsy or brushing, bronchoalveolar lavage, or cerebrospinal fluid.