Clinical question: Is the risk of recurrence of Clostridium difficile infection (CDI) increased by the use of "non-CDI" antimicrobial agents (inactive against C. diff) during or after CDI therapy?
Background: Recurrence of CDI is expected to increase with use of non-CDI antimicrobials. Previous studies have not distinguished between the timing of non-CDI agents during and after CDI treatment, nor examined the effect of frequency, duration, or type of non-CDI antibiotic therapy.
Study design: Retrospective cohort.
Setting: Academic Veterans Affairs medical center.
Synopsis: All patients with CDI over a three-year period were evaluated to determine the association between non-CDI antimicrobial during or within 30 days following CDI therapy and 90-day CDI recurrence. Of 246 patients, 57% received concurrent or subsequent non-CDI antimicrobials. CDI recurred in 40% of patients who received non-CDI antimicrobials and in 16% of those who did not (OR: 3.5, 95% CI: 1.9 to 6.5).
After multivariable adjustment (including age, duration of CDI treatment, comorbidity, hospital and ICU admission, and gastric acid suppression), those who received non-CDI antimicrobials during CDI therapy had no increased risk of recurrence. However, those who received any non-CDI antimicrobials after initial CDI treatment had an absolute recurrence rate of 48% with an adjusted OR of 3.02 (95% CI: 1.65 to 5.52). This increased risk of recurrence was unaffected by the number or duration of non-CDI antimicrobial prescriptions. Subgroup analysis by antimicrobial class revealed statistically significant associations only with beta-lactams and fluoroquinolones.
Bottom line: The risk of recurrence of CDI is tripled by exposure to non-CDI antimicrobials within 30 days after CDI treatment, irrespective of the number or duration of such exposures.
Citation: Drekonja DM, Amundson WH, DeCarolis DD, Kuskowski MA, Lederle FA, Johnson JR. Antimicrobial use and risk for recurrent Clostridium difficile infection. Am J Med. 2011;124:1081.e1-1081.e7.