Outcomes of Two-Stage Revision Surgery with Positive Cultures During Reimplantation

Overview

This study evaluated long-term outcomes of two-stage revision surgeries for hip and knee periprosthetic joint infections (PJI) with positive cultures at reimplantation. It identified risk factors associated with failure and compared reintervention-free survival between patients with positive versus negative cultures at reimplantation.

Background

Periprosthetic joint infections affect approximately 2% of total joint arthroplasty patients and are a leading cause of revision surgery with significant healthcare costs. Two-stage revision surgery, involving prosthesis removal, antibiotic spacer placement, and delayed reimplantation, is the standard treatment for complex PJIs. However, positive cultures at reimplantation occur in 15-30% of cases, and their prognostic significance remains controversial. Understanding the impact of positive cultures and associated risk factors is critical for optimizing patient outcomes.

Data Highlights

The study retrospectively analyzed patients undergoing two-stage revision for hip and knee PJIs between 2016 and 2022 at a high-volume referral center. Inclusion required diagnosis by MSIS 2013 criteria and available histology. Multiple intraoperative samples were collected at explant and reimplantation for microbiological analysis, including sonication fluid cultures. Empirical and targeted antibiotic therapies were administered. Outcomes assessed included treatment failure and reintervention-free survival, stratified by culture results at reimplantation.

Key Findings

• Positive cultures at reimplantation were found in 15-30% of cases, consistent with prior literature.
• Patients with positive cultures had a higher risk of treatment failure and re-revision compared to those with negative cultures.
• Gram-negative bacteria, streptococci, polymicrobial infections, and resistant organisms were associated with worse outcomes.
• Patient factors such as older age, ASA score ≥ III, and McPherson host type C correlated with persistent infection and poorer prognosis.
• Single positive cultures may represent contamination in some cases, but multiple positive cultures increased risk of recurrence.
• Strict microbiological sampling protocols, including sonication and multiple biopsies, improved detection sensitivity.

Clinical Implications

Clinicians should carefully interpret positive cultures at reimplantation, considering pathogen type and patient comorbidities. Multiple positive cultures warrant heightened vigilance and may necessitate tailored antibiotic regimens or surgical strategies. Comprehensive microbiological sampling and a multidisciplinary approach are essential to optimize outcomes in two-stage revision for PJIs.

Conclusion

Positive cultures at reimplantation in two-stage revision surgeries for PJIs are common and associated with increased risk of failure. Identification of specific pathogens and patient risk factors can guide management to improve long-term implant survival.

References

1. 1,2,3 -- Epidemiology and impact of PJI
2. 4,5 -- Projected increase in joint replacements and PJIs
3. 6 -- Limited improvement in PJI treatment outcomes
4. 7,8 -- Two-stage revision surgical technique
5. 9,10 -- Incidence of positive cultures at reimplantation
6. 11,12 -- Prognostic relevance of single vs multiple positive cultures
7. 13,14 -- Pathogen types linked to higher failure and mortality
8. 15,16 -- Patient-related risk factors for poor outcomes
9. 17 -- MSIS 2013 criteria for PJI diagnosis