Periprosthetic joint infections in patients with rheumatoid arthritis are associated with higher complication and mortality rates.

INTRODUCTION: Periprosthetic joint infection (PJI) remains the most devasting complication after total joint arthroplasty (TJA). There has been a significant focus on this topic in recently-published medical literature. However, relatively little has been published about PJI in patients with rheumatoid arthritis (RA), which are often physiologically frail and immunocompromised. A better understanding of PJI in this patient population is therefore crucial. The main aims of this paper are to (1) report complication and mortality rates in a cohort of PJI-RA patients; and (2) clinically characterize them.

METHODS: Medical and surgical records of all RA PJI patients treated surgically from 2003 to 2020 were retrospectively reviewed. Medical history, physical examination, reactive protein (CRP) level, procalcitonin, white blood cell (WBC) count, joint aspiration results, and cultures were used to determine PJI.

RESULTS: 54PJIs, 49 of them chronic, were treated in 53RA patients. Mean patient age was 65 yrs. (range = 32-88); 33females and 20 males (one bilateral hip). The overall mortality rate was 18.9%(n = 10), with five deaths directly attributed to PJI. Staphylococci accounted for 34 infections (63%), while 11(20.4%) had multiorganism infections and six culture-negative PJI. At the end of treatment 79.6%(n = 43) still had an implanted TJR, 7.4% (n = 4) had spacers, 5.6%(n = 3) had undergone resection arthroplasty, 3.7%(n = 2) arthrodesis, and one each amputation and exarticulation.

CONCLUSIONS: Mortality and specially complication rates were (are) high in this RA patients group presenting PJI. Delays to diagnosis and treatment may explain some of these poor outcomes.

LEVEL OF EVIDENCE: A cohort level III retrospective study.