Session: Poster Abstract Session: HAI: Outbreaks
Friday, October 28, 2016
Room: Poster Hall
Background:
In March of 2015, 4 patients grew Mycobacterium farcinogenes senegalense group (M. farcinogenes) from acid-fast bacilli (AFB) sputum cultures collected while housed in the intensive care unit (ICU) of a Veterans Administration Hospital. A review of AFB cultures from the previous 2 years did not reveal any prior M. farcinogenes.
Methods:
A case-control study was performed from January 1, 2015 – January 30, 2016. Cases were patients with sputum cultures positive for M. farcinogenes. Controls were age and gender matched 2:1 from patients with AFB sputum cultures collected. Data collected was age, sex, medical history, admitting symptoms, reason for sputum culture collection, use of nebulizer medications, oxygen requirements, illicit drug use, procedures, location of sputum collection, and hospital days. An investigation of the environment and sputum collection process was performed.
Results:
Case-control
12 cases were identified. All cases had sputum collection while in the ICU and none had clinical disease attributed to M. farcinogenes. Odds ratio (OR) for nebulizer administration was 10 (95% CI 0.6, 166.56, p 0.11); OR for use of ipratropium bromide/albuterol sulfate (IPB/AS) via nebulizer was 4.2 (95% CI 0.25, 69.95, p 0.32), neither factor was statistically significant.
12 cases were identified. All cases had sputum collection while in the ICU and none had clinical disease attributed to M. farcinogenes. Odds ratio (OR) for nebulizer administration was 10 (95% CI 0.6, 166.56, p 0.11); OR for use of ipratropium bromide/albuterol sulfate (IPB/AS) via nebulizer was 4.2 (95% CI 0.25, 69.95, p 0.32), neither factor was statistically significant.
Investigation
No recent construction was performed or common staff identified. Cultures of ICU surfaces, water from the ice machine and sinks in case patient rooms, 3% saline solution used for sputum induction, and IPB/AS nebulizer solution had no mycobacterial growth. The manufacturer of the IPB/AS was contacted and denied other complaints or problems with sterility cultures. The mycobacterial lab switched diagnostic methods from high pressure liquid chromatography to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) approximately 6 months prior to the first culture with M. farcinogenes. M. fortuitum complex samples identified in sputum from 2012-2014 were re-run using MALDI-TOF and all samples were subsequently identified as M. farcinogenes.
No recent construction was performed or common staff identified. Cultures of ICU surfaces, water from the ice machine and sinks in case patient rooms, 3% saline solution used for sputum induction, and IPB/AS nebulizer solution had no mycobacterial growth. The manufacturer of the IPB/AS was contacted and denied other complaints or problems with sterility cultures. The mycobacterial lab switched diagnostic methods from high pressure liquid chromatography to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) approximately 6 months prior to the first culture with M. farcinogenes. M. fortuitum complex samples identified in sputum from 2012-2014 were re-run using MALDI-TOF and all samples were subsequently identified as M. farcinogenes.
Conclusion:
No clear source of the pseudo-outbreak of M. farcinogenes was identified, other than the ICU itself. Further investigation into ICU environmental sources is warranted.
Disclosures:
D. Moritz,
None
S. C. Bleasdale, None
M. K. Sikka, None