Sputum induction as an aid to diagnosis of active cytomegalovirus infection following bone marrow transplantation.

An 8-year-old boy received an allogeneic bone marrow transplant (BMT) for relapsed T cell acute lymphoblastic leukaemia. Because he was seropositive for cytomegalovirus (CMV), serial virological specimens were taken throughout the transplant period, and included those obtained by sputum induction. Sixty-one days following BMT he became unwell, and was found to have mild tachypnoea and reduced oxygen saturations. All investigations were negative, apart from that obtained by sputum induction, which was positive for CMV. He received appropriate therapy with good response. We conclude that the technique of sputum induction can be applied to aid diagnosis of active CMV infection following BMT.