title: Risk factors for recurrent hospital-acquired Clostridium difficile infection in a Japanese university hospital.
abstract: BACKGROUND
  Clostridium difficile infection (CDI) is a highly prevalent hospital-associated infection. Although most patients respond well to discontinuation of antibiotics, 20%-30% of patients relapse. To initiate early therapeutic measures, the risk factors for recurrent CDI must be identified, although very few Japanese studies have used standard surveillance definitions to identify these risk factors.
  
  
  METHODS
  We retrospectively reviewed the medical records of patients with health care facility-onset CDI between August 2011 and September 2013. Patients with diarrhea who were positive for Clostridium difficile (via an enzyme immunoassay) were defined as having CDI. Clinical data (eg, demographics, comorbidities, medication, laboratory results, and clinical outcomes) were evaluated, and multivariate analysis was used to identify risk factors that were associated with recurrent CDI.
  
  
  RESULTS
  Seventy-six health care facility-onset CDI cases were identified, with an incidence rate of 0.8 cases per 10,000 patient-days. Fourteen cases (18.4%) were recurrent, with 13 patients having experienced a single recurrent episode and one patient having experienced three recurrent episodes. The 30-day and 90-day mortality rates were 7.9% and 14.5%, respectively. Multivariate analysis revealed that recurrent patients were more likely to have underlying malignant disease (odds ratio: 7.98; 95% confidence interval: 1.22-52.2; P=0.03) and a history of intensive care unit hospitalization (odds ratio: 49.9; 95% confidence interval: 1.01-2,470; P=0.049).
  
  
  CONCLUSIONS
  Intensive care unit hospitalization and malignancy are risk factors for recurrent CDI. Patients with these factors should be carefully monitored for recurrence and provided with appropriate antimicrobial stewardship.
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Mayu
authors.initials: M
authors.lastname: Hikone
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, Tokyo Women's Medical University, Tokyo, Japan ; Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ainoda
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Tago
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Fujita
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hirai
authors.affiliation: Department of Infectious Diseases, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Takeuchi
authors.affiliation: Department of Internal Medicine, Kitatama Hospital, Tokyo, Japan.
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Totsuka
keywords: Clostridium difficile; recurrent infection; risk factors