Diagnosis of Prosthetic Joint Infection of Hips and Knees—One Size Does Not Fit All

Category	Detail
Condition	Periprosthetic Joint Infection (PJI) of the hip and knee
Key Mechanisms	Infection timing post-arthroplasty (early, delayed, late), host factors, causative microorganisms, and diagnostic scoring systems combining clinical, laboratory, culture, and histological data
Target Population	Adults (≥18 years) undergoing surgical management for first hip or knee PJI
Care Setting	Hospital inpatient setting with surgical intervention

IDSA criteria are most accurate for early (<90 days) PJI and knee infections.
ICM2018 and EBJIS criteria perform better for delayed (90 days–2 years) and late (>2 years) PJI.
Diagnostic approaches should be tailored based on infection timing and joint site rather than using a uniform strategy.

Use IDSA criteria preferentially for early PJI and knee infections.
Apply ICM2018 and EBJIS criteria for delayed and late PJI cases.
Incorporate clinical findings (sinus tract, purulence), inflammatory markers (CRP, ESR), synovial fluid analysis (alpha-defensin, nucleated cell count), culture results (including sonicate cultures), and histology.
Consider timing from arthroplasty to infection onset when selecting diagnostic criteria.

Surgical management is indicated for confirmed PJI cases.
Timing from diagnosis to surgery varies by infection timing (earlier surgery for early PJI).

Monitor inflammatory markers and culture results pre- and post-operatively.
Assess symptom duration and clinical signs consistently across infection timing categories.

Delayed or late PJI may have lower culture positivity and higher bacteremia rates.
Misapplication of diagnostic criteria without considering infection timing may lead to inaccurate diagnosis.

Adults with first-time hip or knee PJI undergoing surgical treatment

Early PJI cases often involve MSSA and CoNS; accurate diagnosis using IDSA criteria can guide timely surgical and antimicrobial therapy.

Tailor diagnostic criteria selection based on infection timing and joint involved.
Use a multidisciplinary approach involving infectious diseases specialists and orthopedic surgeons for diagnosis and management.
Incorporate multiple diagnostic modalities including clinical, laboratory, microbiological, and histological data.
Recognize that sonicate cultures may detect low-level bacterial growth that may not be clinically significant.
Consider demographic and clinical factors but prioritize timing and site for diagnostic accuracy.

Clinical Scorecard: Tailoring Diagnostic Approaches for Hip and Knee Prosthetic Joint Infections: A One-Size-Fits-All Strategy is Inadequate