CHICAGO — Oral metronidazole was comparable to oral
vancomycin in patients with Clostridium difficile infection —
regardless of infection severity, according to data presented by Qamar
Saleheen, MD.
“Although the guidelines do suggest vancomycin for severe illness, our results did not show any difference in the rate of recurrence in severe illness or complications overall between either group," Saleheen, of Hines VA
hospital in Illinois, told Infectious Disease News. "This emphasizes the need to treat every patient on individual basis."
The data were presented during a poster presentation at the 2011
Interscience Conference on Antimicrobial Agents and Chemotherapy.
Despite the SHEA Clostridium difficile diarrhea treatment
guidelines published in May 2010 supporting the use of oral metronidazole for
most non-severe cases of C. difficile and discouraging the use of oral
vancomycin except for severe cases, Saleheen and colleagues observed no
differences in the rate for infection recurrence (P=.41) or
complications between the two treatments (P=.77).
In the retrospective study, researchers examined charts of both
inpatients and outpatients at the hospital (n=147) with positive C.
difficile toxin stools between Jan. 1, 2009 and March 31, 2010. Risk
factors, severity and outcomes of illness were assessed. Patients treated with
metronidazole (n=122) were compared with those treated with vancomycin (n=25).
Of those treated with oral metronidazole, 28 received crossover treatment with
oral vancomycin.
Compared with three of the 14 patients with severe disease that
experienced infection recurrence in the vancomycin group, 16 of the 59 patients
in the metronidazole group with severe disease experienced recurrence.
Further, of the 63 patients with non-severe infection in the
metronidazole group, 11 experienced recurrent infection vs. no recurrent
infections among the 11 patients in the vancomycin group with non-severe
infection. The overall rate for complications with vancomycin was 21 % vs. 22% with metronidazole.
"Our study gives us unique insight into our own institution and prescribing habits of our own clinicians, as we found that clinicians chose treatments irrespective of severity of illness," Saleheen said.The researchers suggest for a large randomized trial to further confirm
these findings. – by Jennifer Henry
Disclosure: Dr. Saleheen reports no relevant financial disclosures.
For more information:
- Saleheen Q. #K-197. Presented at: The 2011 ICAAC; Sept. 17-20;
Chicago.
Herbert L. DuPont, MD
This appears to be a retrospective study comparing outcome of treatment when physicians elected to use metronidazole or to use vancomycin. It is very hard to look at retrospective data and draw conclusions about advantages or disadvantages of one treatment over another. The reason for this is that patients receiving metronidazole would likely be different than patients receiving vancomcyin making the comparison inappropriate. A randomized trial is the only way to be certain about superiority of one treatment over another. More properly controlled experiments are needed to put the relative advantages of the three available treatments in perspective: Metronidazxole, vancomycin vs. fidaxomicin.
– Herbert L. DuPont, MD
Infectious Disease News Editorial Board member
Disclosure: Dr. DuPont reports no relevant
financial disclosures.