617. Investigation of an Outbreak of Serratia marcescens Bloodstream Infections in Patients Receiving Total Parenteral Nutrition — Alabama, 2011
Session: Poster Abstract Session: Outbreak Investigation
Friday, October 21, 2011
Room: Poster Hall B1
  • Gupta,N_IDSA final.pdf (1.3 MB)
  • Background: Serratia marcescens has been associated with outbreaks from contaminated intravenous products.  In March 2011, 5 Serratia bloodstream infections (BSIs) were identified among patients receiving total parenteral nutrition (TPN) at 1 hospital.  Receipt of TPN from a compounding pharmacy (Pharmacy A) was identified as a common source.  An investigation was conducted to determine the extent of the outbreak, confirm common exposures, and identify potential sources of Serratia contamination.

    Methods:  Cases were defined as Serratia BSIs occurring in patients receiving TPN from Pharmacy A between 1/1/2011 and 3/15/2011.  Cases were identified via laboratory and pharmacy record review at facilities receiving TPN from Pharmacy A.  Case-patient clinical records were reviewed to identify common exposures and describe outcomes.  Pharmacy A compounding practices were reviewed and environmental samples were obtained.  Molecular relatedness of patient and environmental Serratia isolates was determined by pulsed-field gel electrophoresis (PFGE).

    Results:  A total of 19 case-patients from 6 hospitals were identified from 1/24/2011 to 3/14/2011 (Figure); there were 9 deaths.  The attack rate among TPN recipients in March was 35%.   There were no pediatric case-patients.  Pharmacy A began compounding and sterilizing amino acids for adult TPN formulations around November 2010 due to a shortage of manufactured amino acids.  Review of this process identified several breaches: poor mixing practices, excessive particulate matter in the pre-filtered solution, changing of the filter during sterilization, and insufficient sampling for sterility testing.  Serratia was identified from the amino acid mixing container, an open bag of L-valine amino acid powder, and a Pharmacy A water faucet.  These isolates were indistinguishable from 13 case-patient blood isolates by PFGE.

    Conclusion:  High-risk compounding of an amino acid component of TPN was initiated due to a national shortage.  Failure to follow several recommended practices resulted in an outbreak of Serratia BSIs with a 47% fatality rate.  In order to avoid similar outbreaks, pharmacies must understand and adhere to current guidelines for compounding sterile preparations.

    Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

    Neil Gupta, MD1,2, Susan N. Hocevar, MD1,2, Heather O'Connell, PhD1, Kelly M. Stevens, MS3, Mary G. McIntyre, MD, MPH3, David T. Kuhar, MD1, Judith Noble-Wang, PhD1 and Alexander Kallen, MD, MPH1, (1)Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, (2)Epidemic Intelligence Service Program, CDC, Atlanta, GA, (3)Bureau of Communicable Disease, Alabama Department of Public Health, Montgomery, AL


    N. Gupta, None

    S. N. Hocevar, None

    H. O'Connell, None

    K. M. Stevens, None

    M. G. McIntyre, None

    D. T. Kuhar, None

    J. Noble-Wang, None

    A. Kallen, None

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.