Authors: Fadel HJ, Osmon DR, Marculescu C, Berbari EF
Title: Prosthetic Joint Infection (PJI) Due to Anaerobic Microorganisms
Institution: Mayo Clinic, Rochester, MN
Purpose: To determine the demographics and outcome of patients with anaerobic PJI.
Methods: All cases of total hip arthroplasty (THA) or total knee (TKA) anaerobic infection diagnosed at our institution between 1/95-12/99 were analyzed. Kaplan-Meier survival methods were used to determine the cumulative probability of success.
Results: Among 510 episodes of PJI during the study period, 3.9% (20/510) were anaerobic PJI (9 PJI with Propionibacterium acnes, 5 with Peptostreptococcus magnus, 2 with Peptostreptococcus micros, 1 with Prevotella melaninogenica, 1 with Veillonella parvula , 1 with Bacteroides vulgatus, 1 with Bacteroides vulgatus and Propionibacterium acnes). The median age of patients was 68 years (range: 44- 82). 55% (11/20) of the episodes occurred in males. 55% (11/20) involved a THA. 95% (19/20) of patients presented with joint pain and only 15 % (3/20) had fever. 45 % (9/20), 20% (4/20), and 5% (1/20) of patients underwent two stage exchange, one stage exchange, and debridement and retention of components respectively. 80% (16/20) of episodes were treated with parenteral antimicrobial therapy, mainly cephalosporin with or without metronidazole with median duration of 35 days (range: 3-63). 4 patients received subsequent chronic suppression. 10% (2/20) were treated with oral antibiotics only. 5% (1/20) of episodes were associated with a dental abscess; none had a concomitant gastrointestinal or urinary pathology. The 2-year cumulative estimate of survival free of treatment failure was 90% (95% CI: 68%-95%).
Discussion and Conclusion: Anaerobic PJI is infrequent at our institution. Systemic symptoms may be minimal at presentation. An association with dental or intraabdominal pathology was not common. Anaerobic PJI treated at our institution is associated with a favorable outcome.