Reconstitution of lymphocyte populations and cytomegalovirus viremia or disease after allogeneic peripheral blood stem cell transplantation.

Early reconstitution of lymphoid populations was monitored by immunophenotyping in 57 allogeneic peripheral blood stem cell (allo-PBSC) transplant patients either with or without cytomegalovirus (CMV) viremia or disease. Cell counts for total lymphocytes and CD4(+) T cells above the percentile 60th at day 14 postransplant were associated significantly with CMV viremia-free survival within 120 days after transplant. Recovery of total lymphocyte, CD3(+), and CD8(+) T-cell counts proceeded at a more rapid rate in CMV viremic patients than in nonviremic patients, irrespective of whether preemptive treatment with ganciclovir had been prescribed. Significant expansion of CD8(+) and CD8(+) CD57(+) T-cell subsets was associated with recovery from viremia and no progression to CMV disease. Immunophenotyping may provide useful information for the clinical management of CMV infection in allo-PBSC transplant recipients.