Does methylene blue affect culture yield in total knee arthroplasty periprosthetic joint infection?
Jordan Villa1,2, Spencer Ward3, Zoe Alpert3
1New York University Langone Orthopedic Hospital, New York, USA. jordancarolinavilla@gmail.com.
Background:
Methylene blue (MB), a phenothiazine dye with antimicrobial activity, is used to stain soft tissues and guide thoroughness of debridement during revision total knee arthroplasty (rTKA) for periprosthetic joint infection (PJI). The purpose of this study was to determine if instillation of MB prior to arthrotomy impacts culture yield in TKA PJI.
Methods:
We retrospectively reviewed 266 patients diagnosed with TKA PJIs according to the 2018 International Consensus Meeting (ICM) criteria from January 2018 - March 2023 at a single academic hospital. Demographics, perioperative outcomes, and preoperative and intraoperative culture positivity were compared between patients who received intraoperative MB (MB group; n = 26) and those who did not (nMB group; n = 241). A record of detected organisms was included in the analysis.
Results:
There was no difference in preoperative aspiration culture positivity between groups. However, the MB group had a higher percentage of preoperative to intraoperative culture concordance (89.5 vs. 69.9%; P = 0.04). Although the overall rate of intraoperative culture positivity did not differ significantly between groups, the MB group had more intraoperative cultures obtained per patient (4.9 vs. 4.5; P = 0.02) and higher numbers of positive intraoperative cultures per patient. Concordance rates for patients in both groups with positive preoperative and negative intraoperative cultures were similar (10.5 vs. 16.5%, P = 0.50). Among patients with negative preoperative cultures, intraoperative culture positivity was more discordant in the MB group (0 vs. 18.8%; P = 0.03). There was no difference in the number of patients that received antibiotics following aspiration (68.4 vs. 49.6%; P = 0.12).
Conclusion:
While MB use did not affect overall culture positivity, it could interfere with intraoperative pathogen detection in patients with negative preoperative cultures. In these cases, MB should be avoided to decrease inaccuracies in intraoperative culture yield. If preoperative cultures are positive, MB may improve surgical debridement and likelihood of infection eradication.
Insights
Methylene blue (MB) instillation in revision total knee arthroplasty (rTKA) for periprosthetic joint infection (PJI) did not impact overall culture positivity. However, MB may interfere with intraoperative pathogen detection in patients with negative preoperative cultures.
Area of Science:
- Orthopedic Surgery
- Infectious Diseases
- Medical Microbiology
Background:
- Methylene blue (MB) is a phenothiazine dye with antimicrobial properties.
- It is utilized in revision total knee arthroplasty (rTKA) to stain tissues and guide debridement for periprosthetic joint infection (PJI).
Purpose of the Study:
- To evaluate the impact of intraoperative methylene blue (MB) instillation on microbiological culture yield in TKA PJI.
Main Methods:
- Retrospective review of 266 patients diagnosed with TKA PJI (2018-2023).
- Comparison of preoperative and intraoperative culture positivity between patients receiving intraoperative MB (n=26) and those not receiving MB (n=241).
Main Results:
- No significant difference in preoperative aspiration culture positivity between groups.
- The MB group showed higher preoperative to intraoperative culture concordance (89.5% vs. 69.9%).
- Intraoperative culture positivity was discordant in the MB group for patients with negative preoperative cultures (0% vs. 18.8%).
Conclusions:
- Methylene blue (MB) instillation does not affect overall culture positivity in TKA PJI.
- MB may interfere with intraoperative pathogen detection when preoperative cultures are negative; avoidance is recommended in such cases.
- If preoperative cultures are positive, MB may enhance surgical debridement and infection eradication.
