title: Clostridium difficile infection (CDI) severity and outcome among patients infected with the NAP1/BI/027 strain in a non-epidemic setting.
abstract: OBJECTIVE
  Determine whether the NAP1 strain identified by polymerase chain reaction (PCR)-based stool assay is correlated with CDI severity and clinical outcomes.
  
  
  METHODS
  Medical records of adult patients with positive stool Xpert® Clostridium difficile PCR assay for an initial episode of CDI between January 2012 and January 2013 at a tertiary care hospital in Chicago were reviewed. Two patients diagnosed with CDI caused by a non-NAP1 strain (positive Xpert® C. difficile assay but negative Xpert® C. difficile Epi assay) were included for each patient diagnosed with CDI caused by a NAP1 strain (positive Epi assay). Patient charts were reviewed for markers of severity, risk factors, treatment regimens, and outcomes.
  
  
  RESULTS
  Of 494 stool specimens, 90 (18%) that were positive for C. difficile by PCR were positive for NAP1 strain. In total, 37 patients with CDI due to NAP1 were matched with 74 patients with CDI due to non-NAP1 strains. Multivariable model revealed individuals ≥65 years old were 3 times more likely to have NAP1 strain than individuals <65 (P=.02). Residents of a nursing home prior to hospitalization were 10 times more likely to have NAP1 strain than patients residing in their homes (P=.001). More NAP1 cases had a change in treatment from metronidazole to oral vancomycin plus intravenous metronidazole (P=.01). The severity of CDI, incidence of mortality and recurrent CDI were similar between groups.
  
  
  CONCLUSIONS
  In a nonepidemic setting, NAP1 strains were more common in older patients and individuals admitted from nursing homes. Identification of NAP1 by PCR of stool specimens was associated in a change of therapy but did not predict worse outcomes. Reporting strain results may not be clinically useful in routine settings.
authors.affiliation: 1Department of Pharmacy,Loyola University Medical Center,Maywood,Illinois,USA.
authors.forename: T
authors.initials: T
authors.lastname: Scardina
authors.affiliation: 1Department of Pharmacy,Loyola University Medical Center,Maywood,Illinois,USA.
authors.forename: L
authors.initials: L
authors.lastname: Labuszewski
authors.affiliation: 2Edward Hines Jr. VA Hospital,Hines,Illinois,USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Pacheco
authors.affiliation: 4Loyola University Chicago,Chicago,Illinois,USA.
authors.forename: W
authors.initials: W
authors.lastname: Adams
authors.affiliation: 5Department of Pathology,Loyola University Medical Center,Maywood,Illinois,USA.
authors.forename: P
authors.initials: P
authors.lastname: Schreckenberger
authors.affiliation: 2Edward Hines Jr. VA Hospital,Hines,Illinois,USA.
authors.forename: S
authors.initials: S
authors.lastname: Johnson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D016360:Clostridioides difficile / Q000145:classification* / Q000302:isolation & purification; D003015:Clostridium Infections / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology / Q000382:microbiology*; D003428:Cross Infection / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058889:Molecular Typing; D015999:Multivariate Analysis; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents