Application of Advanced High-sensitivity Technologies for Identifying Infections in Patients With Aseptic Loosening of Hip Arthroplasty.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 11
- 试验地点
- 1
- 主要终点
- Identification of microorganisms by microbiological cultures (number of patients with positive microbiological culture).
研究概览
简要总结
Recent data showed that the rate of periprosthetic infections in patients undergoing a hip arthroplasty revision for aseptic loosening is higher than what can be ascertained with conventional methods.
The study aims to assess the adequacy of next-generation sequencing of 16s ribosomal ribonucleic acid (rRNA) gene amplicons for identifying occult infections and improving the diagnostic workup. Moreover, additional testing has been planned in order to increase knowledge on the etiopathogenesis of infection.
详细描述
Periprosthetic infection following hip arthroplasty is one of the main causes of implant failure that leads to multiple surgical interventions, prolonged hospitalization, and higher complication rate and mortality.
Recent data prove that the rate of periprosthetic infections is higher than what can be ascertained with conventional techniques and highlight as analytical methods that allow an early and accurate diagnosis may help clinicians identify effective treatment and mitigate the devastating consequences.
New technologies based on culture-independent assays, i.e., the next-generation sequencing (NGS) of 16s rRNA gene amplicons, have entered medical microbiology as an alternative to traditional bacterial identification methods. NGS has been proven to detect microorganisms in culture-negative periprosthetic joint infection and seems to be a valid adjunct in identifying causative pathogens in samples from patients undergoing a hip arthroplasty revision for aseptic loosening.
The microbiota profiling using NGS may also help identify patients prone to develop infections. In predisposing clinical conditions, i.e., obesity and diabetes, the metabolic and nutritional alterations modify the composition and the immunomodulatory properties of intestinal microbiota. Saprophytic, non-pathogenic microorganisms usually found in the intestine and oral cavity can be transferred to other areas becoming a potential source of periprosthetic infection.
Additionally, microorganisms may live in the periprosthetic microenvironment without giving signs of overt infection. However, bacterial products, i.e., "microbe-associated molecular patterns" (MAMPs) or "pathogen-associated molecular patterns "(PAMPs), adhere to the implant surface or the wear particles and may elicit a local inflammatory response characterized by the presence of cells capable of producing cytokines that promote osteoclastogenesis, periprosthetic resorption and consequent loosening of the implant.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Hip arthroplasty revision for aseptic loosening, diagnosis determined as probable according to the following criteria:
- •pain and/or functional impairment;
- •radiographic signs of osteolysis following wear of the implant components, or cortical reaction, or periprosthetic bone resorption;
- •negative evaluation by the infectious disease specialist.
排除标准
- •presence of a sinus tract communicating with the arthroplasty;
- •bacteria isolation from aspirates or blood cultures performed preoperatively;
- •serum C-reactive protein higher than 10 mg/L;
- •recurrent implant dislocations;
- •prosthetic fracture;
- •medical history for septic arthritis, osteomyelitis;
- •infections in anatomic areas other than hip;
- •antibiotic therapy in the 15 days prior to surgery (with the exception of preoperative antibiotic prophylaxis);
- •chronic treatment with immunosuppressive drugs;
- •medical contraindications for executing sample collection.
结局指标
主要结局
Identification of microorganisms by microbiological cultures (number of patients with positive microbiological culture).
时间窗: Within two week of admission
Tissue samples will be sent for microbiological cultures and treated for the isolation of aerobic and anaerobic pathogens. The existence of two positive cultures will be considered to be diagnostic for periprosthetic infection; a single positive culture may occur from a contaminating organism and will be considered in conjunction with other markers of infection, including histological features.
Number of patients with histological features of periprosthetic infection
时间窗: Within two week of admission
The presence of a periprosthetic infection will be established according to the number of polymorphonuclear cells (PMN) counted in ten high-power fields (HPF) (400 × magnification, field diameter 0.54 mm)- Uninfected: 0-5 PMNs in 10 HPFs; borderline, but probably not infected: 6-10 PMNs for 10 HPF; borderline, but probably infected: \>10 PMNs for 10 HPFs (but not \> 5 PMNs in a single HPF); infected \> 5 for HPF.
Identification of microorganisms by next-generation sequencing (NGS) (number of patients with positive NGS).
时间窗: Through study completion, an average of 6 months.
The NGS will be employed to characterize the overall microbiome profile in tissue samples, and bioinformatics used to determine the taxonomic and phylogenetic affiliation, alpha-diversity (ecological diversity of a single sample according to the number of different taxa and their relative abundances), and beta-diversity (differences in microbial community composition between samples).
次要结局
- Characterization of taxonomic and phylogenetic affiliation of gut microbiota(Through study completion, an average of 6 months.)
- Characterization of alpha-diversity and beta-diversity of gut microbiota(Through study completion, an average of 6 months.)
- Characterization of taxonomic and phylogenetic affiliation of oral microbiota(Through study completion, an average of 6 months.)
- Characterization of alpha-diversity and beta-diversity of oral microbiota(Through study completion, an average of 6 months.)
- Number of patients with inflammatory cellular reactivity related to bacterial products.(Through study completion, an average of 6 months.)
研究者
Nicola Baldini
Professor, Director of the Research Innovation & Technology Department
Istituto Ortopedico Rizzoli