Streptococcus mitis septicemia in leukemia patients; clinical features and outcome.

The frequency of streptococcal infections has been reported to be increasing. To determine the significance of such infections complicating treatment of leukemia, we studied the incidence and clinical features of Streptococcus mitis septicemia among 51 leukemia patients in our department. During 166 consecutive treatment courses for leukemia, eight episodes of Streptococcus mitis septicemia were observed in 35 septicemic patients. In seven out of eight episodes (88%), severe mucositis developed after aggressive chemotherapy, suggesting that oral mucosa might be the site of entry for Streptococcus mitis. The isolates were sensitive to imipenam/cilastatin and cefuzonam, and were relatively resistant to amikacin. Although none of the patients died of Streptococcus mitis septicemia, life-threatening adult respiratory distress syndrome (ARDS) developed in two independent treatment courses. We should thus be aware of the risk of ARDS in patients with Streptococcus mitis septicemia.