Chryseobacterium indologenes in four patients with leukemia.

Chryseobacterium indologenes is a rare opportunistic pathogen causing hospital-acquired infection. We present 4 patients with leukemia associated with C. indologenes infection. Two of the patients, undergoing peripheral blood allogeneic hematopoietic stem cell transplantation (alloHSCT) from human leukocyte antigen-identical sibling donors, died of pneumonia caused by C. indologenes with or without Pseudomonas aeruginosa. Blood infection with C. indologenes was found in the other 2 patients during chemotherapy, 1 of which was a central venous catheter-related bloodstream infection. Both patients were cured with or without the sensitive antibiotic. Three of these 4 isolates were susceptible to trimethoprim-sulfamethoxazole only in vitro. Although C. indologenes has a weak toxicity, it can be lethal for the super-immunocompromised patients, such as those treated with alloHSCT.