TNF Inhibitor Therapy May Increase Risk of Serious Post-operative Infection

TNF inhibitor therapy, which has proven successful in reducing inflammation in patients with rheumatoid arthritis, may increase the risk of serious post-operative infections when taken prior to orthopedic surgery, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in San Antonio, Texas.

Genetically-engineered, or biologic, tumor necrosis factor (TNF) inhibitors suppress the TNF proteins that cause joint inflammation, a beneficial therapy in the day-to-day lives of many arthritis patients. However, because the same TNF protein also plays a key role in suppressing infections with certain bacteria in the body, continued use of TNF inhibitors prior to surgery could increase the risk of many types of infections, such as septic arthritis, osteomyelitis or deep wound infection, following surgery.

To assess this post-operative risk, researchers evaluated the outcome of 91 rheumatoid arthritis patients, average age 59.5 years, who underwent bone or joint surgery between Jan. 1, 1999 and March 15, 2004. Patients who developed deep bone or soft tissue infections within 30 days after surgery were identified and their medications were reviewed.

Of 35 patients receiving treatment with a TNF inhibitor at the time of surgery, seven developed a post-operative infection. In contrast, only three of 56 patients not receiving a TNF inhibitor at the time of surgery developed an infection. TNF inhibitor use was associated with a four-fold increase in risk for infection.

TNF inhibitors such as etanercept, infliximab and adalimumab can be discontinued and restarted without impairing the health of patients. However, since each drug has a distinct half-life, patients should ask their physician for pre-surgery guidelines.

"These data are preliminary," said Joan M. Bathon, MD, John Hopkins Arthritis Center, Johns Hopkins University, Baltimore, Maryland, and an investigator in the study. "However, because postoperative infections can be devastating and life threatening, a cautious approach in discontinuing TNF inhibitors prior to bone and joint surgery seems prudent."

The American College of Rheumatology is the professional organization for rheumatologists and health professionals who share a dedication to healing, preventing disability and curing arthritis and related rheumatic and musculoskeletal diseases.

Source: American College of Rheumatology