Related Experiment Video
Updated: May 22, 2026
12:58
A Protocol to Characterize the Morphological Changes of Clostridium difficile in Response to Antibiotic Treatment
Published on: May 25, 2017
Does doxycycline protect against development of Clostridium difficile infection?
Sarah B Doernberg1, Lisa G Winston, Daniel H Deck
1Department of Internal Medicine, Division of Infectious Diseases, University of California, San Francisco, CA 94110, USA. sarah.doernberg@ucsf.edu
Summary
Doxycycline use significantly lowered the risk of Clostridium difficile infection (CDI) in hospitalized patients receiving ceftriaxone. This finding suggests doxycycline may be a valuable adjunct in preventing CDI during high-risk antibiotic therapy.
Area of Science:
- Infectious Diseases
- Pharmacology
- Hospital Epidemiology
Background:
- Antibiotic receipt is a primary risk factor for Clostridium difficile infection (CDI).
- Doxycycline has demonstrated a reduced association with CDI compared to other antibiotics.
- Investigated doxycycline's protective effect against CDI in patients receiving ceftriaxone, an antibiotic linked to higher CDI risk.
Purpose of the Study:
- To determine if concurrent doxycycline administration reduces the incidence of Clostridium difficile infection (CDI) in hospitalized patients treated with ceftriaxone.
- To evaluate the association between doxycycline use and CDI risk in a real-world hospital setting.
Main Methods:
- Retrospective cohort study of adult patients receiving ceftriaxone between June 2005 and December 2010.
- Patients were monitored for CDI occurrence within 30 days of ceftriaxone initiation.
- Multivariable regression analysis adjusted for multiple clinical and demographic factors.
Main Results:
- Overall CDI incidence was 5.60 cases per 10,000 patient-days.
- Patients receiving doxycycline had a significantly lower CDI incidence (1.67 per 10,000 patient-days) compared to those not receiving it (8.11 per 10,000 patient-days).
- Each additional day of doxycycline receipt was associated with a 27% reduction in CDI rate (HR, 0.73; 95% CI, .56-.96).
Conclusions:
- Doxycycline use was associated with a reduced risk of Clostridium difficile infection in patients treated with ceftriaxone.
- Current guidelines suggest this combination for certain community-acquired pneumonia (CAP) cases.
- Further research is warranted to explore doxycycline-containing regimens as a preferred CAP treatment strategy.
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