Late Reinfection May Recur More Than 5 Years After Reimplantation of THA and TKA: Analysis of Pathogen Factors

• Published in: Clinical orthopaedics and related research 2018-02, Vol.476 (2), p.345-352
• Main Authors: Garvin, Kevin L, Miller, Ryan E, Gilbert, Todd M, White, Anthony M, Lyden, Elizabeth R
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Arthroplasty, Replacement, Hip - adverse effects; Arthroplasty, Replacement, Knee - adverse effects; Drug Resistance, Bacterial; Female; Hip Prosthesis - adverse effects; Humans; Incidence; Knee Prosthesis - adverse effects; Male; Middle Aged; Nebraska - epidemiology; Prosthesis-Related Infections - diagnosis; Prosthesis-Related Infections - epidemiology; Prosthesis-Related Infections - microbiology; Prosthesis-Related Infections - surgery; Recurrence; Reoperation; Retrospective Studies; Risk Assessment; Risk Factors; Time Factors; Treatment Outcome
• ISSN: 0009-921X; 1528-1132; 0009-921X
• DOI: 10.1007/s11999.0000000000000050

Two-stage reimplantation has consistently yielded high rates of success for patients with chronic prosthetic joint infection, although results more than 5 years after reimplantation are not commonly reported. Numerous factors may contribute to the risk of reinfection, although these factors-as well as the at-risk period after reimplantation-are not well characterized. (1) What is the risk of reinfection after reimplantation for prosthetic joint infection at a minimum of 5 years? (2) Is the bacteriology of the index infection associated with late reinfection? (3) Is the presence of bacteria at the time of reimplantation associated with late reinfection? Between 1995 and 2010, we performed 97 two-stage revisions in 93 patients for prosthetic joint infection of the hip or knee, and all are included in this retrospective study. During that time, the indications for this procedure generally were (1) infections occurring more than 3 months after the index arthroplasty; and (2) more acute infections associated with prosthetic loosening or resistant organisms. One patient (1%) was lost to followup; all others have a minimum of 5 years of followup (mean, 11 years; range, 5-20 years) and all living patients have been seen within the last 2 years. Patients were considered free from infection if they did not have pain at rest or constitutional symptoms such as fever, chills, or malaise. The patients' bacteriology and resistance patterns of these organisms were observed with respect to recurrence of infection. Odds ratios and Fisher's exact test were performed to analyze the data. The incidence of reinfection was determined using cumulative incidence methods that considered death as a competing event. Reinfection occurred in 12 of the 97 joints resulting in implant revision. The estimated 10-year cumulative incidence of infection was 14% (95% confidence interval [CI], 7%-23%) and incidence of infection from the same organism was 5% (95% CI, 1%-11%). Five occurred early or within 2 years and three were resistant pathogens (methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, or vancomycin-resistant Enterococcus). Seven late hematogenous infections occurred and all were > 4 years after reimplantation and involved nonresistant organisms. Three of the five (60%) early infections were caused by resistant bacteria, whereas all seven late infections were caused by different organisms or a combination of different organisms than were i