C Difficile in Total Knee Arthroplasty Patients

Ronald Delanois, MD

Although rare, Clostridium difficile (C difficile) infection in revision total knee arthroplasty (TKA) patients can be extremely costly, according to new findings.

Investigators from Sinai Hospital of Baltimore reviewed the National Inpatient Sample database between 2009 and 2013 in order to examine the incidence, costs, and risk factors for C difficile infection in TKA patients. They found more than 80,000 patients who underwent revision TKA during that time.

The study authors said that periprosthetic joint infection is the most common cause for revision TKA, and these patients are at risk for significant morbidity and mortality. The treatments for these often require antibiotics, which can lead to development of C difficile infection.

Of those patients who underwent TKA, the researchers found 799 patients, or 1%, who developed C difficile infection during their inpatient stay. There seemed to be a decreasing trend in the overall incidence of C difficile infection between 2009 and 2013, falling from 1.1% to .7% in that time frame.

The team determined the hospital and patient specific characteristics to organize the risk factors for developing C difficile infection, which included older age (69 years vs. 65 years), longer hospital length of stay (11 vs. 5 days), and greater costs (roughly $30,000 vs. roughly $18,000 for patients with and without C difficile infection, respectively).

Hospitals in the Northeast, South, and Western US regions had higher costs than other locations, the researchers learned. Plus, there were increased costs associated with medium-bed-sized hospitals, government/nonfederal hospitals, rural, and urban teaching hospitals. The investigators said that C difficile infection alone was not found to be associated with a significant cost increase, though.

“Our study shows that C difficile is an uncommon, but critically important complication, as it affects care quality and outcomes,” Ronald Delanois, MD, and Nequesha Mohamed, MD, said in a joint statement to MD Magazine®. “It is generally recognized that antibiotic overuse can lead to an increased incidence of C difficile. Our study brings awareness to this issue to help providers be cognizant this avoidable complication.”

The patients who developed C difficile infection also experienced higher in-hospital mortality and were more likely to be treated in an urban, not-for-profit hospitals of medium or large size often located in the Northeast or Midwest. These patients also tended to have underlying depression and/or fluid/electrolyte disorders, the researchers determined.

“We were surprised that despite its rarity, C difficile led to an increase in the length of stay, which was associated with poorer outcomes and increased costs,” Delanois and Mohamed continued. “It is an infrequent complication that leads to a significantly increased cost of care.

The changes we hope to see are better antibiotic selection, as well as a reassessment of the frequency and duration of their use. In fact, the Center for Disease Control and Prevention (CDC) has recommended a decrease in preoperative antibiotic prophylaxis to 1 dose, which is also currently under investigation by the American Association of Hip and Knee Surgeons. We hope those results, combined with our study, will affect how C difficile infection is recognized and managed in arthroplasty.”

The paper, titled “Clostridium difficile infection in the USA: incidence and associated factors in revision total knee arthroplasty patients,” was published in the European Journal of Orthopaedic Surgery & Traumatology.