Two-stage revision in periprosthetic knee joint infections

Periprosthetic joint infection(PJI)following total knee arthroplasty is one of the most catastrophic and costly complications that carries significant patient wellness as well as economic burdens.The road to efficiently diagnosing and treating PJI is challenging,as there is still no gold standard method to reach the diagnosis as early as desired.There are also international controversies with respect to the best approach to manage PJI cases.In this review,we highlight recent advances in managing PJI following knee arthroplasty surgery and discuss in depth the two-stage revision method.

Identification and preoperative optimization of risk factors to prevent periprosthetic joint infection

Despite significant improvements over the past several decades in diagnosis,treatment and prevention of periprosthetic joint infection(PJI),it still remains a major challenge following total joint arthroplasty.Given the devastating nature and accelerated incidence of PJI,prevention is the most important strategy to deal with this challenging problem and should start from identifying risk factors.Understanding and well-organized optimization of these risk factors in individuals before elective arthroplasty are essential to the ultimate success in reducing the incidence of PJI.Even though some risk factors such as demographic characteristics are seldom changeable,they allow more accurate expectation regarding individual risks of PJI and thus,make proper counseling for shared preoperative decision-making possible.Others that increase the risk of PJI,but are potentially modifiable should be optimized prior to elective arthroplasty.Although remarkable advances have been achieved in past decades,many questions regarding standardized practice to prevent this catastrophic complication remain unanswered.The current study provide a comprehensive knowledge regarding risk factors based on general principles to control surgical siteinfection by the review of current literature and also share own practice at our institution to provide practical and better understandings.

RANK-ligand and osteoprotegerin as biomarkers in the differentiation between periprosthetic joint infection and aseptic prosthesis loosening

AIM To assess serum levels of RANK-ligand(RANKL) and osteoprotegerin(OPG) as biomarkers for periprosthetic joint infection(PJI) and compare their accuracy with standard tests.METHODS One hundred and twenty patients presenting with a painful total knee or hip arthroplasty with indication for surgical revision were included in this prospective clinical trial. Based on standard diagnostics(joint aspirate, microbiological, and histological samples) and Musculoskeletal Infection Society consensus classification,patients were categorized into PJI, aseptic loosening,and control groups. Implant loosening was assessed radiographically and intraoperatively. Preoperative serum samples were collected and analyzed for RANKL, OPG, calcium, phosphate, alkaline phosphatase(AP), and the bone-specific subform of AP(b AP). Statistical analysis was carried out, testing for significant differences between the three groups and between stable and loose implants. RESULTS All three groups were identical in regards to age, gender, and joint distribution. No statistically significant differences in the serum concentration of RANKL(P = 0.16) and OPG(P = 0.45) were found between aseptic loosening and PJI, with a trend towards lower RANKL concentrations and higher OPG concentrations in the PJI group. The RANKL/OPG ratio was significant for the comparison between PJI and non-PJI(P = 0.005). A ratio > 60 ruled out PJI in all cases(specificity: 100%, 95%CI: 89, 11% to 100.0%) but only 30% of non-PJI patients crossed this threshold. The positive predictive value remained poor at any cut-off. In the differentiation between stable and loose implants, none of the parameters measured(calcium, phosphate, AP, and b AP) showed a significant difference, and only AP and b AP measurements showed a tendency towards higher values in the loosened group(with P = 0.09 for AP and P = 0.19 for b AP). CONCLUSION Lower RANKL and higher OPG concentrations could be detected in PJI, without statistical significance.

Predicting lower limb periprosthetic joint infections: A review of risk factors and their classification

AIM To undertook a systematic review to determine factors that increase a patient's risk of developing lower limb periprosthetic joint infections(PJI).METHODS This systematic review included full-text studies that reviewed risk factors of developing either a hip or knee PJI following a primary arthroplasty published from January 1998 to November 2016. A variety of keywords were used to identify studies through international databases referencing hip arthroplasty, knee arthroplasty, infection, and risk factors. Studies were only included if they included greater than 20 patients in their study cohort, and there was clear documentation of the statistical parameter used; specifically P-value, hazard ratio, relative risk, or/and odds ratio(OR). Furthermore a quality assessment criteria for the individual studies was undertaken to evaluate the presence of record and reporting bias. RESULTS Twenty-seven original studies reviewing risk factors relating to primary total hip and knee arthroplasty infections were included. Four studies(14.8%) reviewed PJI of the hip, 3(11.21%) of the knee, and 20(74.1%) reviewed both joints. Nineteen studies(70.4%) were retrospective and 8(29.6%) prospective. Record bias was identified in the majority of studies(66.7%). The definition of PJI varied amongst the studies but there was a general consensus to define infection by previously validated methods. The most significant risks were the use of preoperative high dose steroids(OR = 21.0, 95%CI: 3.5-127.2, P < 0.001), a BMI above 50(OR = 18.3, P < 0.001), tobacco use(OR = 12.76, 95%CI: 2.47-66.16, P= 0.017), body mass index below 20(OR = 6.00, 95%CI: 1.2-30.9, P = 0.033), diabetes(OR = 5.47, 95%CI: 1.77-16.97, P = 0.003), and coronary artery disease(OR = 5.10, 95%CI: 1.3-19.8, P = 0.017).CONCLUSION We have highlighted the need for the provider to optimise modifiable risk factors, and develop strategies to limit the impact of non-modifiable factors.

Treatment of periprosthetic knee infection and coexistent periprosthetic fracture:A case report and literature review

BACKGROUND Periprosthetic joint infection(PJI) and periprosthetic fracture(PPF) are among the most serious complications following total knee arthroplasty. Herein, we present one patient with these two complications with details on the characteristics, treatment strategy, and outcome.CASE SUMMARY A 69-year-old female patient who suffered from PJI and PPF following total knee arthroplasty was treated by a two-stage revision surgery. After thorough foreign material removal and debridement, we used a plate that was covered with antibiotic-loaded bone cement to link with a hand-made cement spacer to occupy the joint space and fix the fracture. Although the infection was cured, the fracture did not heal and caused bone defect due to the long interval between debridement and revision. In the revision surgery, a cemented stem and cortical allogenic splints were used to reconstruct the fracture and bone defect. At the final followup 27 mo after revision, the patient was satisfied with postoperative knee functions with satisfactory range of motion(104°) and Hospital for Special Surgery knee score(82 points). The radiographs showed no loosening of the prosthesis and that the bone grafts healed well with the femur.CONCLUSION Our two-stage revision surgery has proved to be successful and may be considered in other patients with PJI and PPF.

Candidal periprosthetic joint infection after primary total knee arthroplasty combined with ipsilateral intertrochanteric fracture: A case report

BACKGROUND Candidal periprosthetic joint infection is a rare and difficult to diagnose complication of total knee arthroplasty.The treatment of such complications is inconclusive and may include prosthesis removal,debridement,arthrodesis,and extensive antifungal therapy to control the infection.CASE SUMMARY A 62-year-old male with a history of total knee arthroplasty(TKA)in his left knee presented with ipsilateral knee pain and a sinus discharge 20 mo after TKA.The patient was previously evaluated for left knee pain,swelling,and a transient fever one month postoperatively.Prothesis removal and insertion of a cement spacer were performed in a local hospital six months prior to the current presentation.Medical therapy included rifampicin and amphotericin which were administered for 4 wk following prosthesis removal.A second debridement was performed in our hospital and Candida parapsilosis was detected in the knee joint.Fourteen weeks following the latter debridement,the patient suffered a left intertrochanteric fracture and received closed reduction and internal fixation with proximal femoral nail anterotation.Two weeks after fracture surgery,a knee arthrodesis with autograft was performed using a double-plate fixation.The patient recovered adequately and was subsequently discharged.At the two-year follow-up,the patient has a stable gait with a pain-free,fused knee.CONCLUSION Fungal periprosthetic joint infection following TKA may be successfully and safely treated with prosthesis removal,exhaustive debridement,and arthrodesis after effective antifungal therapy.Ipsilateral intertrochanteric fractures of the affected knee can be safely fixated with internal fixation if the existing infection is clinically excluded and aided by the investigation of serum inflammatory markers.

Knowledge and attitudes of orthopedic surgeons regarding prosthesis joint infection

BACKGROUND Periprosthetic joint infection(PJI)is a critical complication after joint arthroplasty and is accompanied by increasing rates of morbidity and mortality.Several studies have aimed at preventing PJI.AIM To research the knowledge level and attitudes of orthopedic surgeons,who play a key role in both preventing and managing PJI.METHODS We conducted a web-based survey to evaluate orthopedic surgeons'knowledge level and attitudes regarding PJI.The Likert scale survey utilized consisted of 30 questions which were prepared based on the"Proceedings of the International Consensus on Periprosthetic Joint Infection".RESULTS A total of 264 surgeons participated in the survey.Their average age was 44.8,and 173 participants(65.5%)had more than 10 years of experience.No statistically significant relationship was found between the PJI knowledge of the surgeons and their years of experience.However,participants who worked in training and research hospitals demonstrated higher levels of knowledge than the ones in the state hospitals.It was also noticed that surgeons'knowledge concerning the duration of antibiotic therapy and urinary infections was not consistent with their attitudes.CONCLUSION Even though orthopedic surgeons have adequate knowledge about preventing and managing PJI,their attitudes might contradict their knowledge.Future studies are required to examine the causes and solutions of the contradictions between orthopedic surgeons'knowledge and attitudes.

Two-stage revision arthroplasty for coagulase-negative staphylococcal periprosthetic joint infection of the hip and knee

BACKGROUND Periprosthetic joint infections(PJIs)are frequently caused by coagulase-negative Staphylococci(CoNS),which is known to be a hard-to-treat microorganism.Antibiotic resistance among causative pathogens of PJI is increasing.Two-stage revision is the favoured treatment for chronic CoNS infection of a hip or knee prosthesis.We hypothesised that the infection eradication rate of our treatment protocol for two-stage revision surgery for CoNS PJI of the hip and knee would be comparable to eradication rates described in the literature.AIM To evaluate the infection eradication rate of two-stage revision arthroplasty for PJI caused by CoNS.METHODS All patients treated with two-stage revision of a hip or knee prosthesis were retrospectively included.Patients with CoNS infection were included in the study,including polymicrobial cases.Primary outcome was infection eradication at final follow-up.RESULTS Forty-four patients were included in the study.Twenty-nine patients were treated for PJI of the hip and fifteen for PJI of the knee.At final follow-up after a mean of 37 mo,recurrent or persistent infection was present in eleven patients.CONCLUSION PJI with CoNS can be a difficult to treat infection due to increasing antibiotic resistance.Infection eradication rate of 70%-80%may be achieved.

Good accuracy of the alpha-defensin lateral flow test for hip periprosthetic joint infection: A pilot study in a retrospective cohort of 52 patients

BACKGROUND The alpha-defensin lateral flow(ADLF)test is a new diagnostic tool for periprosthetic joint infection(PJI).Test accuracy for combined cohorts of hip and knee PJI has been reported to be good.AIM To assess the accuracy of the ADLF test for hip PJI,and to compare three different diagnostic criteria for PJI.METHODS A cohort of 52 patients was identified,with a painful or poor-functioning total hip-or hemi-arthroplasty,that underwent aspiration and a subsequent ADLF test.PJI was diagnosed with Musculoskeletal Infection Society(MSIS)criteria,and sensitivity,specificity,overall accuracy,positive predictive value and negative predictive value were calculated.Furthermore,test specifics were compared with the European Bone and Joint Infection Society(EBJIS)and 2018 International Consensus Meeting(ICM)criteria for PJI.RESULTS Using MSIS criteria,sensitivity was 100%(CI:54%-100%)and specificity was 89%(CI:76%-96%).Six true positives and 5 false positives were found,including one case of metallosis.Using EBJIS criteria,more PJIs were found(11 vs 6),sensitivity was lower(71%,CI:42%-92%)and specificity was higher(97%,CI:86%-100%),with 4 false negatives and one false positive result.Using 2018 ICM criteria,sensitivity was 91%(62%-100%)and specificity 100%(91%-100%).The results in this cohort are comparable to previous studies.CONCLUSION Overall test accuracy of the ADLF test was good in this cohort,with a sensitivity of 100%and specificity of 89%.Using different PJI definition criteria,sensitivity and specificity changed slightly but overall accuracy remained around 90%.Using the ADLF test in metallosis cases can result in false positive results and should be performed with caution.

Analysis of the clinical efficacy of two-stage revision surgery in the treatment of periprosthetic joint infection in the knee:A retrospective study

BACKGROUND Periprosthetic joint infection(PJI)is a catastrophic complication that can occur following total knee arthroplasty(TKA).Currently,the treatment for PJI mainly includes the use of antibiotics alone,prosthetic debridement lavage,primary revision,secondary revision,joint fusion,amputation,etc.AIM To explore the clinical effect of two-stage revision surgery for the treatment of PJI after TKA.METHODS The clinical data of 27 patients(3 males and 24 females;age range,47–80 years;mean age,66.7±8.0 years;27 knees)with PJI treated with two-stage revision surgery in our hospital between January 1,2010 and December 31,2020 were analyzed retrospectively.The following outcomes were compared for changes between preoperative and last follow-up results:Erythrocyte sedimentation rate(ESR),C-reactive protein(CRP),visual analogue scale(VAS)scores,Hospital for Special Surgery(HSS)scores,knee range of motion(ROM),and infection cure rates.RESULTS All 27 patients were followed up(range,13–112 mo).The ESR(14.5±6.3 mm/h)and CRP(0.6±0.4 mg/dL)of the patients at the last follow-up were significantly lower than those at admission;the difference was statistically significant(P<0.001).The postoperative VAS score(1.1±0.7),HSS score(82.3±7.1),and knee ROM(108.0°±19.7°)were significantly improved compared with those before the surgery;the difference was statistically significant(P<0.001).Of the 27 patients,26 were cured of the infection,whereas 1 case had an infection recurrence;the infection control rate was 96.3%.CONCLUSION Two-stage revision surgery can effectively relieve pain,control infection,and retain good joint function in the treatment of PJI after TKA.

Preoperative and postoperative risk factors for periprosthetic joint infection in primary total hip arthroplasty:A 1-year experience

BACKGROUND Periprosthetic joint infection(PJI)in primary total hip replacement(THR)is one of the most important threats in orthopedic surgery,so one important surgeon’s target is to avoid or early diagnose a PJI.Although the incidence of PJI is very low(0.69%)in our department,with an average follow-up of 595 d,this infection poses a serious threat due to the difficulties of treatment and the lower functional outcomes after healing.AIM To study the incidence of PJI in all operations occurring in the year 2016 in our department to look for predictive signs of potential infection.METHODS We counted 583 THR for 578 patients and observed only 4 cases of infection(0.69%)with a mean follow-up of 596 d(min 30,max 1451).We reviewed all medical records to collect the data:duration and time of the surgery,presence,type and duration of the antibiotic therapy,preoperative diagnosis,blood values before and after surgery,transfusions,presence of preoperative drugs(in particularly anticoagulants and antiaggregant,corticosteroids and immunosuppressants),presence of some comorbidities(high body mass index,blood hypertension,chronic obstructive pulmonary disease,cardiac ischemia,diabetes,rheumatological conditions,previous local infections).RESULTS No preoperative,intraoperative,or postoperative analysis showed a higher incidence of PJI.We did not find any class with evident major odds of PJI.In our study,we did not find any border value to predict PJI and all patients had similar values in both groups(non-PJI and PJI).Only some categories,such as female patients,showed more frequency of PJI,but this difference related to sex was not statistically significant.CONCLUSION We did not find any category with a higher risk of PJI in THR,probably due to the lack of few cases of infection.

Treatment of acute periprosthetic infections with prosthesis retention: Review of current concepts

Periprosthetic joint infection(PJI) is a devastating complication after total joint arthroplasty, occurring in approximately 1%-2% of all cases. With growing populations and increasing age, PJI will have a growing effect on health care costs. Many risk factors have been identified that increase the risk of developing PJI, including obesity, immune system deficiencies, malignancy, previous surgery of the same joint and longer operating time. Acute PJI occurs either postoperatively(4 wk to 3 mo after initial arthroplasty, depending on the classification system), or via hematogenous spreading after a period in which the prosthesis had functioned properly. Diagnosis and the choice of treatment are the cornerstones to success. Although different definitions for PJI have been used in the past, most are more or less similar and include the presence of a sinus tract, blood infection values, synovial white blood cell count, signs of infection on histopathological analysis and one ormore positive culture results. Debridement, antibiotics and implant retention(DAIR) is the primary treatment for acute PJI, and should be performed as soon as possible after the development of symptoms. Success rates differ, but most studies report success rates of around 60%-80%. Whether single or multiple debridement procedures are more successful remains unclear. The use of local antibiotics in addition to the administration of systemic antibiotic agents is also subject to debate, and its pro's and con's should be carefully considered. Systemic treatment, based on culture results, is of importance for all PJI treatments. Additionally, rifampin should be given in Staphylococcal PJIs, unless all foreign material is removed. The most important factors contributing to treatment failure are longer duration of symptoms, a longer time after initial arthroplasty, the need for more debridement procedures, the retention of exchangeable components, and PJI caused by Staphylococcus(aureus or coagulase negative). If DAIR treatment is unsuccessful, the following treatment option should be based on the patient health status and his or her expectations. For the best functional outcome, one- or two-stage revision should be performed after DAIR failure. In conclusion, DAIR is the obvious choice for treatment of acute PJI, with good success rates in selected patients.

Performance of alpha-defensin lateral flow test after synovial fluid centrifugation for diagnosis of periprosthetic knee infection

BACKGROUND The quantitative alpha-defensin enzyme-linked immunosorbent assay(ELISA)demands a prior synovial fluid centrifugation,whereas this processing is not routinely required prior to the alpha-defensin lateral flow test.AIM To evaluate whether a prior synovial fluid centrifugation could lead the lateral flow performance to achieve comparable results to ELISA during periprosthetic joint infection(PJI)diagnosis.METHODS Fifty-three cases were included in this study:22 classified as PJI and 31 classified as aseptic cases,according to Musculoskeletal Infection Society 2013 criteria.Synovial fluid samples were submitted to centrifugation,and the supernatant was evaluated by ELISA and lateral flow tests.The sensitivity(SE),specificity(SP)and accuracy of each method were calculated as well as the agreement between those two methods.RESULTS In all of the 31 samples from aseptic patients,alpha-defensin ELISA and lateral flow tests showed negative results for infection.Regarding the 22 infected patients,the lateral flow test was positive in 19 cases(86.4%)and the ELISA was positive in 21(95.5%).Sensibility,SP and accuracy were,respectively,86.4%(95%CI:65.1%-97.1%),100%(95%CI:88.8%-100%)and 93.2%(95%CI:82.8%-98.3%)for the lateral flow test and 95.5%(95%CI:77.2%-99.9%),100%(95%CI:88.8%-100%)and 98.1%(95%CI:89.9%-100%)for ELISA.An agreement of 96.2%between those methods were observed.No statistical difference was found between them(P=0.48).CONCLUSION Alpha-defensin lateral flow test showed high SE,SP and accuracy after a prior synovial fluid centrifugation,achieving comparable results to ELISA.Considering the lower complexity of the lateral flow and its equivalent performance obtained in this condition,a prior centrifugation might be added as a valuable step to enhance the PJI diagnosis.

Utility of D-dimer in total joint arthroplasty

As the number of patients receiving total joint replacements continues to rise,considerable attention has been directed towards the early detection and prevention of postoperative complications.While D-dimer has long been studied as a diagnostic tool in venous thromboembolism(VTE),this assay has recently received considerable attention in the diagnosis of periprosthetic joint infection(PJI).D-dimer values are substantially elevated in the acute postoperative period after total joint arthroplasty,with levels often exceeding the standard institutional cutoff for VTE(500µg/L).The utility of D-dimer in detecting VTE after total joint replacement is currently limited,and more research to assess its value in the setting of contemporary prophylaxis protocols is warranted.Recent literature supports D-dimer as a good to excellent biomarker for the diagnosis of chronic PJI,especially when using serum sample technique.Providers should exercise caution when interpreting D-dimer levels in patients with inflammatory and hypercoagulability disorders,as the diagnostic value is decreased.The updated 2018 Musculoskeletal Infection Society criteria,which includes D-dimer levels>860µg/L as a minor criterion,may be the most accurate for diagnosing chronic PJI to date.Larger prospective trials with transparent lab testing protocols are needed to establish best assay practices and optimal cutoff values for D-dimer in the diagnosis of PJI.This review summarizes the most current literature on the value of D-dimer in total joint arthroplasty and elucidates areas for future progress.

Use of topical vancomycin powder in total joint arthroplasty:Why the current literature is inconsistent?

Periprosthetic joint infection(PJI)is a rare but terrible complication in hip and knee arthroplasty,and the use of topical vancomycin powder(VP)has been investigated as a tool to potentially reduce its incidence.However,there remains no consensus on its efficacy.Therefore,the aim of this review is to provide an overview on the application of topical vancomycin in orthopaedic surgery focusing on the recent evidence and results in total joint arthroplasty.Several systematic reviews and meta-analyses on topical VP in hip and knee arthroplasty have been recently published reporting sometimes conflicting results.Apart from all being limited by the quality of the included studies(mostly level III and IV),confounding variables are often included potentially leading to biased conclusions.If taken into consideration the exclusive use of VP in isolation,the available data,although very limited,suggest that it does not reduce the infection rate in routine primary hip and knee arthroplasty.Therefore,we still cannot advise for a routinary application.A properly powered randomized-controlled trial would be necessary to clarify the role of VP in hip and knee arthroplasty.Based on the analysis of the current evidence,the use of topical VP appears to be safe when used locally in terms of systemic adverse reactions,hence,if proven to be effective,it could bring great benefits due to its low cost and accessibility.

聚维酮碘对家兔创面组织浸泡冲洗的影响

背景:临床上人工关节置换所面临的最危险、最严重的并发症就是发生人工关节假体周围感染,找到一个能够预防人工关节置换假体周围感染的方法是迫切需要的。目的:观察聚维酮碘对家兔肌肉、血管、脂肪和骨质等组织进行浸泡冲洗后的影响。方法:选取40只10周龄雄性新西兰大白兔,每只兔子的左后腿作为实验组,右后腿作为对照组。兔后肢麻醉后切开,显露后肢的肌肉、血管、脂肪和骨质,对照组手术切口内用生理盐水浸泡和冲洗;实验组手术切口内用聚维酮碘原液及生理盐水浸泡和冲洗。40只兔分别在浸泡聚维酮碘0,1,3,5 min时随机处死10只切取创面组织标本,采用苏木精-伊红染色制片,对细胞数目及分布进行统计学分析和比较。结果与结论:①经聚维酮碘浸泡冲洗的肌肉、血管、脂肪和骨质与生理盐水对照组相比,镜下未见其细胞结构、形态及数目有明显的差异;②运用配对t检验探究对照组与实验组之间的差异性,配对数据均没有呈现出差异性(P>0.05);③提示聚维酮碘对家兔肌肉、血管、脂肪和骨质等组织进行浸泡冲洗后与生理盐水相比未见明显差异,反映了聚维酮碘溶液作为创口内消毒剂的安全有效性。

滑液中PRTN3和MNDA诊断关节假体周围感染的效能:与α-防御素的比较

目的检测关节滑液中标志物蛋白酶3(proteinase 3,PRTN3)和髓样细胞核分化抗原(my-eloid nuclear differentiation antigen,MNDA)在关节假体周围感染(periprosthetic joint infection,PJI)诊断中的临床效能,并与传统标志物α-defensin进行比较。方法回顾性收集连续65例因怀疑PJI而进行髋膝关节诊断性穿刺病人的关节滑液标本。基于2014年肌肉骨骼感染协会(Musculoskeletal Infection Soci-ety,MSIS)标准,将29例纳入PJI组,36例纳入非PJI组。随后使用商用ELISA试剂盒检测关节滑液中的三种标志物水平。采用受试者工作特征(receiver operating characteristic,ROC)曲线分析评价所研究生物标志物的诊断效能,并计算其各自的敏感度、特异度与截断值。结果PJI组菌培养结果以葡萄球菌为主,占比31%,培养阴性病人占比34.5%。ROC分析结果显示,PRTN3的曲线下面积(area under the curve,AUC)最大,为0.984(95%CI,0.961~1.000),其次是α-defensin,AUC为0.944(95%CI,0.888~1.000),最后为MNDA,AUC为0.849(95%CI,0.755~0.943)。PRTN3的最佳截断值为318.000(ng/mL),敏感度为0.931,特异度为0.972。α-defensin的最佳截断值为7.150(μg/mL),敏感度为0.931,特异度为0.861。MNDA的最佳截断值为4.318(ng/mL),敏感度为0.862,特异度为0.722。结论PRTN3和MNDA都是PJI的优秀生物标志物。PRTN3的诊断性能最好,甚至略优于α-defensin。

关节置换术后假体周围感染病原菌分布特点及耐药情况

目的分析髋膝关节置换术后假体周围感染病原菌分布特点和耐药情况,为临床预防和合理使用抗菌药物提供参考。方法回顾性收集并分析2020年1月—2022年12月某院收治的髋膝关节置换术后假体周围感染患者的临床资料,分析病原菌分布及对常用抗菌药物的耐药情况。结果共纳入105例关节置换术后假体周围感染患者,其中,髋关节置换67例,膝关节置换38例。共检出病原菌124株,以革兰阳性菌株为主,占74.19%(92株);其次是革兰阴性菌,占16.13%(20株);最常见的病原菌是金黄色葡萄球菌(37.90%,47株)和凝固酶阴性葡萄球菌(22.58%,28株)。药敏试验结果显示,革兰阳性球菌中,金黄色葡萄球菌、凝固酶阴性葡萄球菌对苯唑西林的耐药率分别为26.67%、73.08%,对万古霉素均敏感;革兰阴性菌对环丙沙星、哌拉西林/他唑巴坦、头孢曲松耐药率分别为33.33%、41.18%、55.56%,对美罗培南敏感。结论关节置换术后,假体周围感染主要病原菌为金黄色葡萄球菌和凝固酶阴性葡萄球菌,后者对苯唑西林耐药率较高。经验性治疗对金黄色葡萄球菌假体周围感染可能有效,但对凝固酶阴性葡萄球菌假体周围感染可能效果差。

局部应用万古霉素预防全膝关节置换切口早期感染

背景:全膝关节置换过程中使用万古霉素是一种存在争议的切口感染预防策略,目前国内对于此预防措施的疗效评估缺乏相关证据。目的:评估全膝关节置换过程中局部使用万古霉素对术后早期切口感染的预防效果。方法:纳入2022年3-6月在安徽医科大学第一附属医院关节外科接受初次单侧全膝关节置换的膝骨关节炎患者120例,随机分为观察组和对照组,每组60例,所有患者对治疗方案均知情同意。观察组患者术中局部应用万古霉素1 g,对照组术中不使用万古霉素,记录两组患者术后第1,3,5天红细胞沉降率、C-反应蛋白、术后连续7 d发热率、膝关节肿胀程度、累计引流量及术后1年假体周围关节感染的发生率,评估全膝关节置换术中局部应用万古霉素对于术后早期切口感染的预防效果。结果与结论:①两组患者术后第1,3,5天红细胞沉降率和C-反应蛋白水平相比差异均无显著性意义(P>0.05);②两组患者术后连续7 d发热率相比差异均无显著性意义(P>0.05);③两组患者术后膝关节肿胀程度和累积引流量相比差异均无显著性意义(P>0.05);④两组患者术后1年内均未发生假体周围关节感染,差异无显著性意义(P>0.05);⑤结果提示,全膝关节置换过程中局部使用万古霉素在术后早期预防切口感染方面未见明显疗效。

基于药学角度的假体周围感染常用抗菌药物关节腔内联合给药的可行性分析

目的从药学角度考察假体周围感染(Periprosthetic joint infection,PJI)常用关节腔抗菌药物联合方案的可行性,以期为其临床合理配伍提供依据。方法参考2020版《中国药典》标准,在室温下分别测定万古霉素(VAN)+美罗培南(MEM)、VAN+左氧氟沙星(LEV)、利奈唑胺(LZD)+MEM、LZD+LEV、LZD+哌拉西林他唑巴坦(PTZ)等配伍组合放置0 min、30 min、60 min、2 h、3 h、6 h后的澄清度、不溶性微粒数、pH值和渗透压,评估各组合的物理配伍稳定性。采用液质联用(HPLC-MS)技术检测上述配伍液中各药物的百分含量,评估各组合的化学稳定性。结果①VAN与MEM配伍后,物理和化学稳定性欠佳:澄清度(大量沉淀产生)、药物百分含量明显改变(VAN、MEM百分含量分别降低了12.23%、72.43%)。②VAN与LEV配伍后,物理稳定性欠佳,化学稳定性较好:不溶性微粒数超过《中国药典》相关标准,pH值低于人体耐受范围;③LZD与MEM配伍后,物理化学稳定性欠佳:澄清度明显改变(浅黄色),不溶性微粒数超过《中国药典》相关标准,药物百分含量明显改变(MEM百分含量降低了10.98%);④LZD与LEV配伍后,物理和化学稳定性欠佳:渗透压(<300 mOsm/L)低于健康关节液渗透压,LZD百分含量降低了11.63%;⑤LZD与PTZ配伍后,物理稳定性欠佳,化学稳定性较好:不溶性微粒数超过《中国药典》相关标准,渗透压(>600 mOsm/L)明显高于健康关节液。结论VAN+MEM、LZD+MEM 2种配伍组合不稳定,应避免联用;VAN+LEV、LZD+LEV、LZD+PTZ 3种配伍组合用于PJI的局部治疗可能是可行的,建议混合后采取过滤措施,并避免长期输注。