Application of next-generation sequencing technology in the detection of pathogenic bacteria of the periprosthetic joint infection after arthroplasty

[Study on effectiveness of antibiotics guided by metagenomic next-generation sequencing to control infection after total knee arthroplasty]

Objective

To explore the clinical value of metagenomic next-generation sequencing (mNGS) in diagnosis and treatment of periprosthetic joint infection (PJI) after total knee arthroplasty (TKA).

Methods

Between April 2020 and March 2023, 10 patients with PJI after TKA were admitted. There were 3 males and 7 females with an average age of 69.9 years (range, 44-83 years). Infection occurred after 8-35 months of TKA (mean, 19.5 months). The duration of infection ranged from 16 to 128 days (mean, 37 days). The preoperative erythrocyte sedimentation rate (ESR) was 15-85 mm/1 h (mean, 50.2 mm/1 h). The C reactive protein (CRP) was 4.4-410.0 mg/L (mean, 192.8 mg/L). The white blood cell counting was (3.4-23.8)×10 9/L (mean, 12.3×10 9/L). The absolute value of neutrophils was (1.1-22.5)×10 9/L (mean, 9.2×10 9/L). After admission, the joint fluid was extracted for bacterial culture method and mNGS test, and sensitive antibiotics were chosen according to the results of the test, and the infection was controlled in combination with surgery.

Results

Seven cases (70%) were detected as positive by bacterial culture method, and 7 types of pathogenic bacteria were detected; the most common pathogenic bacterium was Streptococcus lactis arrestans. Ten cases (100%) were detected as positive by mNGS test, and 11 types of pathogenic bacteria were detected; the most common pathogenic bacterium was Propionibacterium acnes. The difference in the positive rate between the two methods was significant ( P=0.211). Three of the 7 patients who were positive for both the bacterial culture method and the mNGS test had the same results for the type of pathogenic bacteria, with a compliance rate of 42.86% (3/7). The testing time (from sample delivery to results) was (4.95±2.14) days for bacterial culture method and (1.60±0.52) days for mNGS test, and the difference was significant ( t=4.810, P<0.001). The corresponding sensitive antibiotic treatment was chosen according to the results of bacterial culture method and mNGS test. At 3 days after the one-stage operation, the CRP was 6.8-48.2 mg/L (mean, 23.6 mg/L); the ESR was 17-53 mm/1 h (mean, 35.5 mm/1 h); the white blood cell counting was (4.5-8.1)×10 9/L (mean, 6.1×10 9/L); the absolute value of neutrophils was (2.3-5.7)×10 9/L (mean, 4.1×10 9/L). All patients were followed up 12-39 months (mean, 23.5 months). One case had recurrence of infection at 6 months after operation, and the remaining 9 cases showed no signs of infection, with an infection control rate of 90%.

Conclusion

Compared with bacterial culture method, mNGS test can more rapidly and accurately detect pathogenic bacteria for PJI after TKA, which is important for guiding antibiotics combined with surgical treatment of PJI.

Corynebacterium striatum Periprosthetic Hip Joint Infection: An Uncommon Pathogen of Concern?

BACKGROUND

Total hip arthroplasty is indubitably a dominant elective surgery in orthopaedics, contributing to prodigious improvement in the quality of life of patients with osteoarthritis. One of the most potentially devastating complications of this operation is periprosthetic joint infection. Immunocompromised patients might be afflicted by infrequent low-virulence organisms not typically detected with conventional procedures. Consequently, employing advanced identification methods, such as the circumstantial sonication of orthopaedic implants, could be crucial to managing such cases.

CASE PRESENTATION

We present a peculiar case of a 72-year-old female patient suffering from a chronic periprosthetic hip infection due to Corynebacterium striatum. The pathogen was only identified after rigorous sonication of the extracted implants. The overall management of this case was immensely exacting, primarily because of the patient's impaired immune system, and was finally treated with two-stage revision in our Institution.

LITERATURE REVIEW

Although copious literature exists concerning managing periprosthetic hip infections, no concrete guidelines are available for such infections in multimorbid or immunocompromised patients with rare low-virulence microorganisms. Hence, a diagnostic work-up, antibiotic treatment and appropriate revision timeline must be determined. Sonication of extracted implants could be a powerful tool in the diagnostic arsenal, as it can aid in identifying rare microbes, such as Corynebacterium spp. Pertinent antibiotic treatment based on antibiogram analysis and apposite final revision-surgery timing are the pillars for effective therapy of such infections.

CLINICAL RELEVANCE

Corynebacterium striatum has been increasingly recognized as an emerging cause of periprosthetic hip infection in the last decade. A conspicuous rise in such reports has been observed in multimorbid or immunocompromised patients after the COVID-19 pandemic. This case is the first report of Corynebacterium striatum periprosthetic hip infection diagnosed solely after the sonication of extracted implants. This paper aims to increase awareness surrounding Corynebacterium spp. prosthetic joint infections, while highlighting the fields for further apposite research.