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Mark Coventry Award: Human Knee Has a Distinct Microbiome: Implications for Periprosthetic Joint Infection
Diana Fernández-Rodríguez1, Colin M Baker2, Saad Tarabichi2
1Rothman Orthopaedic Institute, Philadelphia, Pennsylvania; Plan de Estudios Combinados en Medicina (PECEM) MD/PhD, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Background:
Pathogens causing prosthetic joint infection (PJI) are thought to gain access to the knee during surgery or from a remote site in the body. Recent studies have shown that there is a distinct microbiome in various sites of the body. This prospective study, and first of its kind, was set up to investigate the presence of possible microbiome in human knee and compare the profile in different knee conditions.
Methods:
We obtained synovial fluid from 65 knees (55 patients) with various conditions that included normal knee, osteoarthritis (OA), aseptic revision, and those undergoing revision for PJI. The contralateral knee of patients who had a PJI were also aspirated for comparison. A minimum of 3 milliliters of synovial fluid was collected per joint. All samples were aliquoted for culture and next-generation sequencing analysis.
Results:
The highest number of species was found in native osteoarthritic knees (P ≤ .035). Cutibacterium, Staphylococcus, and Paracoccus species were dominant in native nonosteoarthritic knees, and meanwhile a markedly high abundance of Proteobacteria was observed in the osteoarthritic joints. Moreover, the contralateral and aseptic revision knees showed a similar trend in bacterial composition (P = .75). The sequencing analysis of patients who had PJI diagnosis, confirmed the culture results.
Conclusion:
Distinct knee microbiome profiles can be detected in patients who have OA and other knee conditions. The distinct microbiome in the knee joint and the close host-microbe relationships within the knee joint may play a decisive role in the development of OA and PJI.
Insights
The human knee harbors distinct microbial communities that differ based on knee condition. Understanding these knee microbiomes may be key to preventing osteoarthritis and prosthetic joint infections.
Area of Science:
- Orthopedics
- Microbiology
- Genomics
Background:
- Prosthetic joint infection (PJI) often originates from surgical site contamination or remote infections.
- Distinct body site microbiomes are increasingly recognized.
- The knee joint's microbiome and its role in knee conditions remain largely unexplored.
Purpose of the Study:
- To investigate the presence and profile of the human knee microbiome.
- To compare knee microbiome composition across different knee conditions, including osteoarthritis (OA) and PJI.
Main Methods:
- Prospective study involving synovial fluid aspiration from 65 knees across various conditions (normal, OA, aseptic revision, PJI).
- Samples analyzed using culture and next-generation sequencing.
- Comparison included contralateral knees in PJI patients and aseptic revision cases.
Main Results:
- Osteoarthritic knees exhibited the highest species diversity.
- Dominant bacteria in non-osteoarthritic knees included Cutibacterium, Staphylococcus, and Paracoccus.
- Osteoarthritic joints showed a high abundance of Proteobacteria.
- Bacterial composition in contralateral and aseptic revision knees was similar.
- Sequencing confirmed culture findings in PJI patients.
Conclusions:
- Distinct knee microbiome profiles are identifiable in patients with OA and other knee conditions.
- The knee joint's unique microbiome and host-microbe interactions may influence the development of OA and PJI.
