Patients taking antibiotics face a greater risk of developing a Clostridium difficile infection, but a new study suggests that this might not be the only risk factor. Patients who occupied a bed which previously held a patient who was treated with antibiotics, have been found to face a higher risk of contracting a C. difficile infection.
C. difficile is often found in the gut of healthy individuals, however it can cause an infection in some people, leading to symptoms such as diarrhea, abdominal pain and fever. Transmission of the bacterium occurs when a patient comes in contact with a surface – such a toilet or bathing tub – which has become contaminated with feces. As such, this infection is common in hospital settings.
“Exposure to C. difficile infection is common in the hospital because C. difficile spores are capable of persisting in the environment for months,” said Dr. Daniel Freedberg, of the Columbia University Medical Center in New York, and his colleagues. “When one hospital roommate has C. difficile infection, patients who share that room are at increased risk for C. difficile infection. Furthermore, when the previous occupant of a given hospital room has C. difficile infection, the subsequent patient in that room is at increased risk for C. difficile infection.”
As antibiotics kill off some of the beneficial bacterial which keep opportunistic pathogens in-check, C. difficile infection can occur in patients being treated with the drugs. The current study – which was published in the journal, JAMA Internal Medicine – found that treating patients with antibiotics during their stay in the hospital, had a further impact on the infection risk for future patients.
Using health data collected from patients 18 years and older, the researchers analyzed the number of times the patients were admitted to four New York hospitals between 2000 and 2015. Patients were included in the analysis provided that they occupied their hospital bed for at least 48 hours, and that the same bed had previously been occupied by another patient for at least 24 hours, over one week before the second patient was admitted.
Prior patients were determined to have been given antibiotics based on a computerized clinician order entry system. Patients who had a history of C. difficile infections, along with those who tested positive for the bacteria within 48 hours of admission, were excluded from the study.
Freedberg and his colleagues identified 100,615 patient pairs who had occupied the same hospital bed. Of the over 100,000 pairs initially identified, 576 of them resulted in the second patient developing a C. difficile infection between two and 14 days after arriving at the hospital.
According to the researchers, these subsequent patients were 22 percent more likely to develop a C. difficile infection, if the hospital bed was previously occupied by a patient on antibiotics. Even accounting for a number of cofounding factors, such as type of ward and patient comorbidities, the results were still found to be statistically significant.
“The increase in risk was small but is of potential importance given the frequency of use of antibiotics in the hospital,” said the researchers. “These data imply that patient-to-patient transmission of C. difficile or other bacteria that mediate susceptibility to C. difficile infection takes place in the non-outbreak setting, and in the face of a multifaceted effort seeking to prevent healthcare-associated C. difficile infection. More generally, these data support the hypothesis that antibiotics given to one patient may alter the local microenvironment to influence a different patient’s risk for C. difficile infection.”