Full bibliography

Summary:

Key Question: What are the epidemiology, diagnosis, and treatment outcomes of CN PJI compared to culture-positive PJI?

Findings:

• Prevalence of CN PJI ranged from 0-42.1% in studies.
• Major risk factors were prior antibiotic use and postoperative wound drainage.
• Detection of CN PJI was based on the results of inaccurate and inappropriate diagnostic tools for rare organisms such as fungi, mycobacterium, and fastidious bacteria that are not easily detected through routine methods
• Most common antibiotics used were vancomycin and cephalosporins.
• Two-stage revision arthroplasty had high treatment success rates of 70-100%.
• Most studies found no significant differences in outcomes between CN PJI and culture-positive PJI.

Clinical Implications:

• CN PJI is a clinically important entity that requires careful diagnosis and treatment.
• Prior antibiotic use should be considered as it can compromise culture results.
• Molecular techniques may improve diagnosis when standard cultures are negative.
• Two-stage revision arthroplasty is likely the best surgical treatment option.

Strengths:

• Systematic review of multiple studies on CN PJI
• Included studies used standard PJI diagnostic criteria
• Provided overview of diagnosis, treatment, and outcomes for CN PJI

Limitations:

• All included studies were retrospective case series, moderate risk of bias
• Heterogeneity in specific diagnostic methods and antibiotic regimens used
• Did not quantitatively synthesize results across studies

Level of evidence:

Moderate

Rationale: This was a systematic review of retrospective studies, which provides low level evidence. However, given the reasonably sized samples and consistency of findings across multiple studies, the overall body of evidence for the key outcomes is moderate. Further prospective cohort studies or randomized trials would improve the evidence quality.