A Cluster of Central Line–Associated Bloodstream Infections Due to Rapidly Growing Nontuberculous Mycobacteria in Patients with Hematologic Disorders at a Japanese Tertiary Care Center: An Outbreak Investigation and Review of the Literature

Abstract

BACKGROUND Rapidly growing nontuberculous mycobacteria (RGM) are considered rare pathogens, causing central line-associated bloodstream infection. We identified an outbreak of central line-associated bloodstream infection due to RGM at a hematology-oncology ward during a 5-month period. DESIGN Outbreak investigation and literature review. SETTING A Japanese tertiary care center. PATIENTS Adults who were hospitalized at the hematology-oncology ward from October 15, 2011, through February 17, 2012. RESULTS A total of 5 patients with a bloodstream infection due to RGM (4 cases of Mycobacterium mucogenicum and 1 case of Mycobacterium canariasense infection) were identified; of these, 3 patients had acute myeloid leukemia, 1 had acute lymphocytic leukemia, and 1 had aplastic anemia. Four of the 5 patients received cord blood transplantation prior to developing the bloodstream infection. All central venous catheters in patients with a bloodstream infection were removed. These patients promptly defervesced after catheter removal and their care was successfully managed without antimicrobial therapy. Surveillance cultures from the environment and water detected M. mucogenicum and M. canariasense in the water supply of the hematology-oncology ward. The isolates from the bloodstream infection and water sources were identical on the basis of 16S-rRNA gene sequencing. CONCLUSIONS The source of RGM in the outbreak of bloodstream infections likely was the ward tap water supply. Awareness of catheter-related bloodstream infections due to nontuberculous mycobacteria should be emphasized, especially where immunocompromised patients are at risk. Also, using antimicrobials after catheter removal to treat central line-associated bloodstream infection due to RGM may not be necessary. Infect Control Hosp Epidemiol 2015;36(1): 76-80.

Bloodstream infections with rapidly growing nontuberculous mycobacteria

“…RGM BSI has been described in mostly immunosuppressed patients, frequently secondary to malignancies and their entailed therapies [23] , [24] , [25] , [26] . Mizusawa et al showed in a small cohort of 17 immunocompetent patients that 94% of patients were persons who inject drugs (PWID), highlighting the role of skin barrier breakdown in this patient population.…”

Outbreak of non-tuberculous mycobacteria in a paediatric bone marrow transplant unit associated with water contamination of needle-free connectors and literature review

“…A literature review identified eight previous outbreaks of CLABSI due to RGM [ 4 – 11 ]. A total of 43 patients were affected; 21 were children.…”

“…A total of 43 patients were affected; 21 were children. All of these outbreaks occurred on haematology–oncology units and half involved HSCT patients [ 4 , 7 , 8 , 11 ].…”

“…The presumed mechanism of contamination of the CVC and NC was with tap water during bathing and showering, when the lines were not adequately covered. Therefore, CVC handling guidelines were reviewed and NCs changed to a different model, which have been successful strategies in previous similar reports [ 4 , 5 , 8 – 11 ]. An education programme on CVC care for families was updated and education for healthcare staff refreshed.…”

Draft Genome Sequence of Mycobacterium mucogenicum Strain CSUR P2099

“…Mycobacterium mucogenicum is a rapid-growing mycobacterium formerly known as a Mycobacterium chelonae –like organism ( 1 , 2 ). M. mucogenicum was commonly implicated in outbreaks of opportunistic infections traced to contaminated water systems ( 3 , 4 ) and contaminated hospital equipment ( 5 – 7 ). Catheter-related infections are the major form of M. mucogenicum opportunistic infection ( 8 , 9 ), and M. mucogenicum is the leading mycobacterium to cause catheter-related bloodstream infections ( 9 ).…”