2068. Change in Distribution of Clostridium difficile NAP1 Strain in Patient Population in the North Suburbs of Chicago.
Session: Poster Abstract Session: Clostridium difficile: Epidemiology
Saturday, October 29, 2016
Room: Poster Hall
  • IDweek 2016. Usacheva. NAP1 distrubution.pdf (739.7 kB)
  • Background: Colstridium difficileinfection (CDI) is a significant healthcare concern worldwide, recognized as the most frequent etiologic agent of healthcare-associated infectious diarrhea in hospitalized adult patients. For the last a few decades steady increase of CDI incidence along with higher morbidity and mortality has been associated with the emergence and rapid spread of NAP1 strain. NAP1 is implicated in many CDI outbreaks and possibly associated with increased morbidity and mortality. However, lately it has been noted that the prevalence of epidemic NAP1 strain is declining. The aim of this work was to determine any change in prevalence and distribution of NAP1 between 2013 and 2015.

    Methods: NorthShore University HealthSystem is a 750 bed, 4-hospital system in the northern suburbs of Chicago. The Cepheid Xpert C. difficile/Epi test was used on all inpatient and outpatients with 3 or more diarrheal stools to detect CDI. We compared the prevalence of NAP1 C. difficilestrains during a 9 month period in 2013 (Period 1) to the same period in 2015 (Period 2). A nosocomial case was defined when disease was diagnosed ≥ 3 days hospital admission.Laboratory data was collected from the all patients by SoftLab reports. We analyzed differences using Fisher's exact test.
















    Results: In total, 8680 stools were tested for C. difficile: 4200 in Period 1 and 4480 in Period 2. Compared data found the prevalence and incidence of NAP1 in inpatients were slightly lower in Period 2 (3% vs 2%, p=0.007 and 4% vs 2.3%, p=0.005, respectively). However, we did not observe significant differences in NAP1distributions in nosocomial vs. non-nosocomial inpatients. The majority of NAP1 positive inpatients were not acquired nosocomially (75%). Interestingly, in Period 2 almost 60% of all NAP1 positives were detected in outpatients. The number of NAP1 positive outpatients was significantly increased compare to 2013 (p=0.0004).

    Conclusion: Our results indicate that distribution of Clostridium difficile NAP1 strain is shifting from hospital to the outpatient setting in our patient population. When determine trends in NAP1 disease it is important to consider both in- and outpatient CDI.

    Elena Usacheva, Ph.D., Pritzker School of Medicine, University of Chicago, Chicago, IL; Departments of Pathology and Laboratory Medicine, and Medicine, NorthShore University HealthSystem, Evanston, IL, Donna Schora, MT(ASCP), Laboratory Medicine, and Medicine, NorthShore University HealthSystem, Evanston, IL, Becky Smith, MD, Infectious Diseases, Pritzker School of Medicine, University of Chicago, Chicago, IL and Lance Peterson, MD, FIDSA, FSHEA, Pritzker School of Medicine, University of Chicago, Chicago, IL


    E. Usacheva, None

    D. Schora, None

    B. Smith, None

    L. Peterson, None

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