Conventional and molecular diagnostic strategies for prosthetic joint infections

Abstract

An accurate diagnosis of prosthetic joint infection (PJI) is the mainstay for an optimized clinical management. This review analyzes different diagnostic strategies of PJI, with special emphasis on molecular diagnostic tools and their current and future applications. Until now, the culture of periprosthetic tissues has been considered the gold standard for the diagnosis of PJI. However, sonication of the implant increases the sensitivity of those cultures and is being increasingly adopted by many centers. Molecular diagnostic methods compared with intraoperative tissue culture, especially if combined with sonication, have a higher sensitivity, a faster turnaround time and are not influenced by previous antimicrobial therapy. However, they still lack a system for detection of antimicrobial susceptibility, which is crucial for an optimized and less toxic therapy of PJI. More studies are needed to assess the clinical value of these methods and their cost–effectiveness.

Keywords::

• diagnostic methods
• molecular diagnostics
• prosthetic joint infection

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Prosthetic joint infections (PJIs) are one of the main problems related to orthopedic surgery, and its importance is expected to increase in the future.

• Diagnosis of PJI is still a challenging area in modern medicine. Syndromic diagnosis can be achieved through a combination of clinical data, image tests and cytochemistry. However, confirming the infection and performing a correct etiologic diagnosis is more difficult, but at the same time, it is crucial for an optimized clinical management of patients.

• The etiologic diagnosis of PJI can be achieved by culture- or nonculture-based methods.

• Conventional culture-based methods can obtain a high percentage of diagnoses using a combination of synovial fluid culture, periprosthetic tissue sample cultures and implant sonication. Nevertheless, despite the important advance of sonication, there are still some patients without diagnosis.

• For these cases, nonculture-based methods are being studied. Molecular technology is probably the most reported one including both homemade techniques and modified commercial tests. Broad-range PCR (16S rDNA as target) and multiplex PCR are the approaches that have shown the most interesting results and probably are ready to be integrated in laboratory routine for some cases with negative results with conventional techniques.

• Other nonculture-based methods, such as matrix-assisted laser desorption/ionization–TOF, Ibis, fluorescent stains (including FISH), pyrosequencing or microcalorimetry are under research with promising results.

• The most effective diagnostic strategy is likely formed by a combination of conventional and new diagnostic strategies for PJI.

• The future could be the use of microchips that integrates organism detection and a ‘molecular antibiogram’ through detection of resistance genes. Nevertheless, the introduction of these techniques has provided new questions, and interpreting the results is not always clear. To clarify these issues, integration of clinical and laboratory activities is essential.

• The optimal management of patients with PJI has to be performed with a multidisciplinary approach with strict collaboration between infectious diseases specialists, orthopedic surgeons and clinical microbiologists in order to optimize the diagnosis and treatment of these complex infections.