Do Antibacterial Cement Spacers Help Treat Prosthetic Joint Infections?

http://www.medscape.com/viewarticle/770438

From Reuters Health Information
Do Antibacterial Cement Spacers Help Treat Prosthetic Joint Infections?


By Will Boggs, MD

NEW YORK (Reuters Health) Sep 06 - In two-stage revisions of infected prosthetic joints, does temporary placement of antibacterial cement spacers improve the outcome? In a recent literature review, researchers at the U.S. Food and Drug Administration couldn't find a conclusive answer to that question.

"Data on the role of antibacterials in spacers is limited and have not been evaluated in randomized clinical trials," coauthors Dr. Dmitri Iarikov and Dr. Sumathi Nambiar told Reuters Health by email. "In addition, the safety profile of the spacers has not been systematically evaluated, especially with regard to renal and vestibular toxicity. Case reports indicate that renal toxicity related to their use is possible."

But the lack of evidence in their favor hasn't kept antibacterial cement spacers from being widely used, the researchers say.

The two authors and their colleagues conducted a systematic review of published studies reporting results of two-stage knee and/or hip arthroplasty and compared infection eradication rates associated with spacers of different antibacterial composition.

The spacers are usually left in place for six to eight weeks. Patients also receive systemic antibiotics, as the authors noted in a report online August 23rd online in Clinical Infectious Diseases.

Ultimately, their review included 20 publications involving 824 patients with 836 infected joints. None of the studies was randomized, and all studies of knee spacers were case series without controls.

The investigators estimated infection eradication rates ranging from 46% to 100%, but the retrospective design and different levels of detail in the studies precluded a combined analysis.

There was no obvious difference overall in infection eradication rates when cements with different antibacterial loads and compositions were used.

The analysis also suggested that prosthetic joint infections could be successfully treated even when antibacterials added to spacers were not active against the infecting organisms.

Rates of renal impairment after placement of antibacterial cement spacers ranged from 0% to 10%, but the noncomparative retrospective designs did not allow for conclusions regarding the relationship between spacers and renal failure.

"The addition of antibacterials to interim spacers for the treatment of prosthetic joint infections has become standard of care with the emphasis to use at least 3.6-4 g of antibacterials per 40 g of cement," the researchers note. "However, no clinical data supporting these recommendations have been identified."

SOURCE: http://bit.ly/TmF700

Clin Infect Dis 2012.

The Choice and Doses of Antibacterial Agents for Cement Spacers in Treatment of Prosthetic Joint Infections: Review of Published Studies

D. Iarikov,
H. Demian,
D. Rubin,
J. Alexander, and
S. Nambiar

+Author Affiliations
U.S. FDA, Silver Spring, MD
Corresponding Author: D. Iarikov, MD, PhD, Division of Anti-infective products, U.S. Food and Drug Administration, Tel. 301-796-2292, E-mail: Dmitri.Iarikov@fda.hhs.gov


Alternate Corresponding Author: Sumathi Nambiar, MD, Division of Anti-infective products, U.S. Food and Drug Administration, Tel: 301-796-0772, E-mail:Sumathi.Nambiar@fda.hhs.gov