Objective:To investigate the clinical characteristics and risk factors for patients with chronic periprosthetic joint infection (PJI) combined with sinus tract.Methods:The patients with PJI following hip and knee arthroplasty from July 2014 to January 2020 in our institution were retrospectively reviewed. There were 96 males and 101 females, aged from 26 to 86 years with mean age of 62.02±13.54 years. There were 95 hip PJI patients (48.2%, 95/197), 102 knee PJI patients (51.8%, 102/197), 68 patients (34.5%, 68/197) with sinus tract, 129 patients (65.5%, 129/197) without sinus tract, 162 patients (82.2%, 162/197) with positive culture results and 35 patients (17.8%, 35/197) with negative culture results. The patients were divided into two groups according to the sinus tract formation. The diagnosis of PJI was based on the 2011 Musculoskeletal Infection Society (MSIS) criteria. All of the included patients underwent serological laboratory tests (white blood cell count, neutrophil percentage, lymphocyte percentage, hemoglobin, platelet count, mean platelet volume, urea, creatinine, albumin, erythrocyte sedimentation rate, C-reactive protein) and pathogen isolation. The influence of sinus tract on the above test and the effects of complications on sinus tract formation were analyzed. We further investigated the relationship between sinus tract formation and the features of pathogen. In addition, the risk factors for sinus tract formation were analyzed.Results:The mean values of all serological tests were without statistical difference between the groups with and without sinus tract ( P>0.05). The presence of complications had no effect on the occurrence of sinus tract ( P>0.05). The incidence of sinus tract with highly virulent pathogen infection group (52.1%, 25/48) was significantly higher than that in low virulence pathogen group (27.5%, 19/69), in culture negative patients (40.0%, 14/35) and in other cases (22.2%, 10/45; χ 2=11.519, P=0.009). There was no statistical difference between groups based on the Gram staining, antibiotic resistance and polymicrobial infection. Multivariate logistic regression analysis revealed positive associations of extra joint infections ( OR=4.426, 95% CI: 1.095, 17.884) and high virulent pathogen infections ( OR=2.633, 95% CI: 1.171, 5.918) and negative association of age ≥70 ( OR=0.436, 95% CI: 0.205, 0.927) with the risk of sinus tract formation. Conclusion:The presence of sinus tract has no effect on the routine serum tests in patients with chronic PJI. There is only virulence factor which might affect sinus tract formation. For patients with the extra joint infections and high virulence pathogen infections, the formation of sinus tract should be vigilant during treatment.

【Objective】 To establish a management information system (referred to as the system) for plasma collection stations in Zhejiang province, so as to explore the current situation of plasma donors and implement effective supervision in Zhejiang. 【Methods】 The system was developed and connected to four plasma collection stations that were officially operating in Zhejiang in terms of plasma station setting and approval, as well as the publicity, recruitment and management of plasma donors, information management of the whole process of plasma collection, management of deferral plasma donors, plasma quality management and administrative supervision etc. Relevant plasma donor information was uploaded to the system by each plasma station, and information before (January 2016 to December 2020) and after (January 8, 2021 to June 2021) the system was collected. Information included the number of plasma donors/donations, demographic information of eligible plasma donors in the past 5 years, the type of plasma donors, and the deferral donors after the system was activated. The online approval of Plasma Donation Certificate and the intelligent supervision of key points of plasma apheresis stations in Zhejiang were also conducted. The frequency and composition ratio were described, and chi-square test was used for statistical analysis. 【Results】 The system (V1.0) was established and was officially launched on January 8, 2021, realizing the interconnection of blood donation and plasma donation information as well as the unified management of 24 quality indicators. Since the system was applied (January 8, 2021-June 2021), the proportion of donors both donated blood and plasma over the province was 3.56 (832/23 389), and 352 deferred donors were masked by the system. And 30.11% (106/352) , who intended to donate plasma, were deferred due to insufficient interval after blood donation; 11.65% (41/352) due to permanent masking in blood donations; 23.86% (23.86%) , who intended to donate blood, were deferred due to insufficient interval after plasma donation ( 84/352); 34.38% (121/352) due to permanent masking in plasma donations. The median approval rate of four plasma stations applying for Plasma Donation Certificate before the system (January 1, 2016 to January 7, 2021) and after the system (January 8 to June 2021) were 93.38% (10 609/11 361) vs 99.50% (2 602/2 615). Before the system was put into launch, the ratio of male to female donors and the proportion of regular donors showed an overall upward trend, while the age decreased slightly. The median proportion of women in the past 5 years was 61.52 %, significantly higher than that in last 6 months after the launch(58.86%). 【Conclusion】 The application of the system can realize information interconnection between blood centers and plasma collection stations in Zhejiang as well as the real-time supervision of plasma collection process, which is helpful to overcome the shortcomings in plasma donor management.