title: Clinical predictors of recurrent Clostridium difficile infection in out-patients.
abstract: BACKGROUND
  Clostridium difficile infection (CDI) recurs in 20-30% of patients.
  
  
  OBJECTIVE
  To describe the predictors of recurrence in out-patients with CDI.
  
  
  METHODS
  Out-patient cases of CDI in Olmsted County, MN residents diagnosed between 28 June 2007 and 25 June 2010 were identified. Recurrent CDI was defined as recurrence of diarrhoea with a positive C. difficile PCR test from 15 to 56 days after the initial diagnosis with interim resolution of symptoms. Patients who had two positive tests within 14 days were excluded. Cox proportional hazard models were used to assess the association of clinical variables with time to recurrence of CDI.
  
  
  RESULTS
  The cohort included 520 out-patients; 104 had recurrent CDI (cumulative incidence of 17.5% by 30 days). Univariate analysis identified increasing age and antibiotic use to be associated with recurrent CDI. Severe CDI, peripheral leucocyte count and change in serum creatinine >1.5-fold were not. In a multiple variable model, concomitant antibiotic use was associated with risk of recurrent CDI (HR = 5.4, 95% CI 1.6-17.5, P = 0.005), while age (HR per 10 year increase = 1.1, 95% CI 0.9-1.3, P = 0.22); peripheral leucocyte count >15 × 10(9) /L (HR = 1.0, 95% CI 0.5-2.1, P = 0.92); and change in serum creatinine greater than 1.5-fold (HR = 0.8, 95% CI 0.4-1.5, P = 0.44) were not.
  
  
  CONCLUSIONS
  Antibiotic use was independently associated with a dramatic risk of recurrent Clostridium difficile infection in an out-patient cohort. It is important to avoid unnecessary systemic antibiotics in patients with Clostridium difficile infection, and patients with ongoing antibiotic use should be monitored closely for recurrent infection.
authors.affiliation: Divisions of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA.
authors.forename: R
authors.initials: R
authors.lastname: Shivashankar
authors.forename: S
authors.initials: S
authors.lastname: Khanna
authors.forename: P P
authors.initials: PP
authors.lastname: Kammer
authors.forename: W
authors.initials: W
authors.lastname: Scott Harmsen
authors.forename: A R
authors.initials: AR
authors.lastname: Zinsmeister
authors.forename: L M
authors.initials: LM
authors.lastname: Baddour
authors.forename: D S
authors.initials: DS
authors.lastname: Pardi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care / Q000706:statistics & numerical data; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D016360:Clostridioides difficile / Q000235:genetics; D003015:Clostridium Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000235:genetics / Q000382:microbiology; D004269:DNA, Bacterial / Q000032:analysis; D003967:Diarrhea / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D016016:Proportional Hazards Models; D012008:Recurrence; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial