Pericarditis after allogeneic peripheral blood stem cell transplantation caused by Legionella pneumophila (non-serogroup 1)

A case of Legionella pericarditis caused by a Legionella pneumophila isolat e other than serogroup 1 is reported in a 59-year-old man after allogeneic peripheral blood stem cell transplantation. On admission a 5 mm pericardial effusion was detected on echocardiography. Antibodies were detected agains t L. pneumophila serogroups 7 to 14 using the antigen pool and against sero group 12 alone. Antibodies were not detected against the serogroup 1 to 6 a ntigen pool, The patient's clinical condition improved dramatically after t reatment with clarithromycin and an echocardiography revealed the total dis appearance of the pericardial effusion.