Periprosthetic gout flare after total knee arthroplasty: A misdiagnostic case report / 北京大学学报(医学版)

Periprosthetic gout flare is a rare arthritic condition after total knee arthroplasty, but the symptoms of gout may have often been mistaken as acute periprosthetic infection given their similarity. Misdiagnosis as periprosthetic infection can lead to unnecessary surgery, long-term dependence on anti-biotics, and even malfunction of the involved knee joint. Here, we report a case study of a patient with immunodeficiency condition of long-term oral glucocorticoid and diabetes mellitus, who had undergone a knee replacement 8 weeks before. The initial symptoms of fever and joint pain together with the dysfunction of her right knee with elevated inflammatory markers, such as increased serum leukocytes, erythrocyte sedimentation rate, C-reactive protein, and synovial cell counts led to a diagnosis of acute periprosthetic infection. Arthrocentesis and bacterial culture were performed preoperatively. According to the current Musculoskeletal Infection Society (MSIS) criteria for diagnosis of periprosthetic infection, the case was classified as periprosthetic infection and a prosthesis retained debridement surgery was performed. However we got negative culture results in all the pre-operative and intro-operative samples. The symptoms as well as the laboratory inflammatory markers improved shortly after the debridement surgery until the 11th day when all the similar systemic and local symptoms recurred. With a remedial crystal analysis of synovial fluid from the patient, gouty flare was found to be the cause of acute arthritis finally. Accor-dingly, after anti-gout medications were administrated, the symptoms associated with acute arthritis gra- dually subsided, and there was no recurrence during a 24-month follow-up. This article described the cli-nical manifestation, diagnosis and differential diagnosis, treatment of a case of periprosthetic gout. Although relatively rare, gout should be considered as a differential diagnosis in suspected periprosthetic infection. Current criteria for periprosthetic infection can not exclude the diagnosis of periprosthetic gout flare, it is therefore imperative that the analysis of joint aspirate for crystals be conducted to determine the correct course of treatment, or unnecessary surgical procedure may be performed in periprosthetic gout case.

Accuracy of Serological Markers, Synovial Fluid, Microbiological Culture, and Histopathological Examination for Diagnosing Periprosthetic Knee Infection / Acurácia dosmarcadores sorológicos, do líquido sinovial, cultura microbiológica e exame histopatológico para o diagnóstico de infecção periprotética do joelho

Abstract Objective This study assessed the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of serological tests, synovial fluid markers, microbiological tissue culture, and histopathological examination of the periprosthetic membrane in diagnosing periprosthetic knee infection. Methods This study is prospective, and it includes patients undergoing total knee arthroplasty revision surgery from November 2019 to December 2021. The analysis consisted of serological tests (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and D-dimer), synovial fluid markers (leukocyte and polymorphonuclear cell counts), periprosthetic tissue culture, and histopathological examination of the periprosthetic membrane of all patients. Results Sixty-two patients had periprosthetic joint infection (PJI) according to the 2018 International Consensus Meeting criteria (infection group), while 22 subjects had no infection. ESR sensitivity and specificity were 83.6% and 45.4%, respectively. CRP sensitivity and specificity were 64.5% and 100%, whereas D-dimer sensitivity and specificity were 78.9% and 25%, respectively. Leukocyte count sensitivity and specificity were 75.6% and 100%, polymorphonuclear cell count sensitivity and specificity were 33% and 100%, respectively. Periprosthetic tissue culture sensitivity and specificity culture were, respectively, 77.4% and 100%. Histopathological examination sensitivity and specificity were 43.7% and 100%, respectively. Conclusions In our study, the total blood cell count in synovial fluid and microbiological cultures of periprosthetic tissues were the most accurate tests for PJI diagnosis. In contrast, polymorphonuclear cell percentage was the least accurate test for PJI diagnosis.

Resumo Objetivo avaliar a sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácia dos testes sorológicos, dos marcadores do líquido sinovial, da cultura microbiológica de tecidos e do exame histopatológico da membrana periprotética para o diagnóstico de infecção periprotética do joelho. Métodos estudo prospectivo, com pacientes submetidos à cirurgia de revisão de artroplastia total do joelho no período entre novembro de 2019 e dezembro de 2021. Foi realizado análise do marcadores sorológicos (VHS,PCR e D-dímero), do líquido sinovial (contagem de leucócitos e percentual de polimorfonucleares), cultura de tecidos periprotéticos e exame histopatológico da membrana periprotética de todos os pacientes. Resultados 62 pacientes foram diagnosticados com infecção periprotética do joelho, pelos critérios do International Consensus Meeting 2018 (grupo infecção) e 22 pacientes integraram o grupo não infecção. A sensibilidade e especificidade da VHS foram de 83,6% e 45,4%, respectivamente. Os valores de sensibilidade e especificidade da PCR foram de 64,5% e 100% e as do D-dímero foram de 78,9%% e 25%, respectivamente. A sensibilidade e especificidade da contagem de leucócitos foi de 75,6% e 100%, e a do percentual de polimorfonucleares foi de 33% e 100%, respectivamente. A sensibilidade e especificidade das culturas de tecidos periprotéticos foi de, respectivamente, 77,4% e 100% A sensibilidade do exame histopatológico foi de 43,7% e a especificidade de 100%. Conclusões A contagem total de leucócitos no líquido sinovial e as culturas microbiológicas dos tecidos periprotéticos foram os testes de maior acurácia para o diagnóstico de infecção periprotética em nossa série. O percentual de polimorfonucleares foi o teste de menor acurácia, em nosso estudo, para o diagnóstico de infecção periprotética.

Infecciones periprotésicas en artroplastia total de rodilla: ¿cuál es nuestra realidad? / Periprosthetic infections in total knee arthroplasty: what is our reality?

INTRODUCCIÓN La infección periprotésica (IPP) es una de las complicaciones más serias en una artroplastia total de rodilla (ATR). Pese a esto, existe poca literatura chilena respecto de esta patología. OBJETIVOS Determinar la incidencia, las comorbilidades, los microorganismos aislados y su susceptibilidad antibiótica, y la morbimortalidad en pacientes con IPP. MATERIALES Y MÉTODOS Estudio descriptivo y retrospectivo en pacientes operados entre 2001 y 2020 por gonartrosis, con una ATR primaria, en un mismo centro de salud, con al menos 1 año de seguimiento. Se excluyeron pacientes operados en otros centros o con registros clínicos incompletos. Se registraron las comorbilidades, los microorganismos aislados, la susceptibilidad antibiótica, y la sobrevida por medio de una búsqueda sistemática de las fichas clínicas de los pacientes con IPP. Se utilizó estadística descriptiva para presentar los datos. RESULTADOS Se incluyeron 544 ATRs, de las cuales 8 (1,47%) presentaron IPP, y los pacientes tenían una edad promedio de presentación de 66 (±5,7) años, e índice de masa corporal (IMC) promedio de 30,3 (±4,5) kg/m2. La mediana de tiempo de presentación de la IPP fue de 411 (±1.034) días. Las principales comorbilidades registradas fueron hipertensión arterial en 5 (62,5%), tabaquismo en 4 (50%) casos, y dislipidemia in 4 (50%) casos. En total, 5 (62,5%) pacientes presentaron etiología polimicrobiana, y en 3 (37,5%) se aisló un solo microorganismo. Los principales agentes aislados fueron Staphylococcus aureus y Staphylococcus coagulasa negativo, ambos multirresistentes, en 6 (75%) y 3 (37,5%) pacientes respectivamente. Todos los pacientes recibieron tres dosis de cefazolina como profilaxis quirúrgica. Se describe una sensibilidad del 100% frente a vancomicina y rifampicina (12/12 cultivos), y una resistencia del 83,4% al ciprofloxacino (4/9 cultivos). Un total de 2 (25%) pacientes fallecieron después de 3 años de la ATR por causas no relacionadas con la IPP. No hubo casos de recidiva infecciosa tras la revisión. CONCLUSIÓN Se encontró una incidencia de 1,47% (8 casos) de IPP. Todos los pacientes con IPP presentaron alguna comorbilidad prequirúrgica. Los principales agentes microbiológicos identificados fueron multirresistentes y susceptibles a vancomicina y rifampicina.

INTRODUCTION Periprosthetic infection (PPI) is one of the most serious complications in total knee arthroplasty (TKA). Despite this, there is little Chilean literature regarding this pathology. OBJETIVES To determine the incidence, comorbidities, isolated microorganisms and their antibiotic susceptibility, morbidity, and mortality in patients with PPI. MATERIALS AND METHODS A descriptive and retrospective study in patients operated between 2001 and 2020 for gonarthrosis, with a primary TKA, in the same health center, with at least 1 year of follow-up. Patients operated on in other centers or with incomplete clinical records were excluded. Comorbidities, isolated microorganisms, antibiotic susceptibility, and survival were recorded through a systematic search of the clinical records of patients with PPI. Descriptive statistics were used to present the data. RESULTS We included 544 TKAs, 8 (1.47%) of which presented PPI, and the patients had an average age at presentation of 66 years ( 5.7 years) and an average body mass index (BMI) of 30.3 ( 4, 5) kg/m2 . The median time of presentation of the PPI was of 411 ( 1,034) days. The main comorbidities recorded were arterial hypertension in 5 (62.5%), smoking in 4 (50%) cases, and dyslipidemia in 4 (50%) cases. In total, 5 (62.5%) patients presented polymicrobial etiology, and in 3 (37.5%), a single microorganism was isolated. The main isolated agents were Staphylococcus aureus and coagulasenegative Staphylococcus, both multidrug-resistant, in 6 (75%) and 3 (37.5%) patients respectively. All patients received three doses of cefazolin as surgical prophylaxis. A sensitivity of 100% to vancomycin and rifampicin (12/12 cultures), and a resistance of 83.4% to ciprofloxacin (4/9 cultures) were described. Overall, 2 (25%) patients died 3 years after the TKA, due to causes unrelated to PPI. There were no cases of infectious relapse after the review. CONCLUSION An incidence of 1.47% (8 cases) of PPI was found. All patients with PPI presented some presurgical comorbidity. The main microbiological agents identified were multidrug-resistant and susceptible to vancomycin and rifampicin

Caracterización microbiológica y patrones de resistencia a antibióticos de las infecciones periprotésicas en pacientes sometidos a remplazo articular de rodilla o cadera, operados en la IPS Universitaria Clínica León XIII, entre el 2015 y 2018 / Microbiological characterization and antibiotic resistance patterns of periprosthetic infections in patients undergoing knee or hip joint replacement, operated at IPS Universitaria Clínica León XIII between 2015 and 2018 / Caracterização microbiológica e padrões de resistência a antibióticos das infecções periprotéticas em pacientes submetidos a artroplastia de joelho ou quadril, operados na IPS Universitária Clínica León XIII, entre 2015 e 2018

Objetivo: caracterizar desde el punto de vista microbiológico las infecciones periprotesicas (IP) de los pacientes sometidos a remplazo articular de rodilla o cadera, en la IPS universitaria Clínica León XIII, y evidenciar los patrones más comunes de resistencia a los antibióticos, en el periodo 2015-2018. Metodología: se recolectó información de 25 pacientes llevados a remplazo articular de rodilla o cadera en la IPS universitaria, sede Clínica León XIII, durante el periodo de 2015-2018, que desarrollaron IP. Se obtuvo información sobre características demográfica, clínicas y patrones de resistencia (según antibiograma), y sobre los criterios usados para diagnosticarla. Los datos se registraron, según la naturaleza y distribución de la variable, en medias o medianas para las variables cuantitativas, y en frecuencias para las cualitativas. Resultados: entre 2015 y 2018 se realizaron 541 remplazos articulares, la incidencia de infección periprotésica fue de 4.6% (25 pacientes), 22 casos (88%) con crecimiento microbiológico. El germen más frecuente fue el S. aureus, con patrón alto de resistencia para meticilina (SAMR), en el 44%. Seguido por K. pneumoniae, con un patrón de resistencia por producción de betalactamasas de espectro extendido (BLEE) de 83%. Ninguno tuvo resistencia a los carbapenémicos. Conclusiones: los resultados son similares a los reportados en la literatura internacional. Sigue siendo el S. aureus el principal causante de la infección periprotésica, seguido de los gérmenes gram negativos.

Objective: to microbiologically characterize the periprosthetic infections (PI) of patients undergoing knee or hip joint replacement at IPS Universitaria Clínica León XXIIIin the period 2015-2018, and to demonstrate the most common antibiotic resistance patterns. Methodology: the information was collected from 25 patients undergoing knee or hip joint replacement at IPS Universitaria Clínica León XXIII during the period 2015-2018 who developed PI. Data was obtained on demographic, clinical characteristics, and antibiotic resistance patterns (according to antibiograms), as well as on the diagnostic criteria used to diagnose it. The data was recorded, according to the nature and distribution of the variable, in means or medians for the quantitative variables, and in frequencies for the qualitative variables.Results:between 2015-2018, 541 joint replacements were performed. There was an incidence of periprosthetic infection in 25 patients (4.6%), 22 of whom (88%) had micro-biological growth. The most frequent germ was S. aureus, which had a high resistance pattern for methicillin-resistant S. aureus (MRSA) in 44%, followed by K. pneumoniaewith a positive extended spectrum beta-lactamase (ESBL) in 83%. None of them showed resistance to carbapenems.Conclusions: the results found are similar to those reported in the international lite-rature. This investigation evidenced that S. aureus continues to be the main cause of periprosthetic infection, followed by gram-negative germs.

Objetivo: caracterizar do ponto de vista microbiológico as infecções periprotéticas (IP) dos pacientes submetidos à artroplastia articular do joelho ou do quadril, na IPS universitário, Clínica León XIII, e demonstrar os padrões mais comuns de resistência aos antibióticos, em o período 2015-2018.Metodologia: foram coletadas informações de 25 pacientes encaminhados para prótese de joelho ou quadril no IPS universitário, sede da Clínica León XIII, no período 2015-2018, que desenvolveram IP. Foram obtidas informações sobre as características demográfi-cas, clínicas e padrões de resistência (de acordo com antibiograma) e sobre os critérios usados para diagnosticá-la. Os dados foram registrados, de acordo com a natureza e distribuição da variável, em médias ou medianas para as variáveis quantitativas e em frequências para as qualitativas.Resultados: entre 2015 e 2018, foram realizadas 541 substituições articulares, a incidência de infecção periprotética foi de 4,6% (25 pacientes), 22 casos (88%) com crescimento microbiológico. O germe mais frequente foi S. aureus, com alto padrão de resistência à meticilina (MRSA), em 44%. Seguido por K. pneumoniae, com padrão de resistência devido à produção de beta-lactamase de espectro estendido (ESBL) de 83%. Nenhum apresentou resistência aos carbapenêmicos.Conclusões: os resultados são semelhantes aos relatados na literatura internacional. S. aureus continua a ser a principal causa de infecção periprotética, seguido por germes gram-negativos.

Application of one-stage revision in the treatment of periprosthetic infection after knee and hip joint replacement / 国际外科学杂志

Periprosthetic infection is a catastrophic complication after joint replacement. Choosing appropriate treatment for patients with different infection characteristics is the key to improve the success rate. The one-stage revision has been applied and studied more and more in clinical work because of its advantages in treatment cycle, functional recovery, complications and cost. Grasping the indications and contraindications, comprehensive analysis and selection of appropriate patients, considering intraoperative details and postoperative anti-infection treatment meticulously, are crucial to reduce the recurrence rate of infection. The purpose of this paper is to describe the main points of the one-stage revision in the treatment of periprosthetic infection, and to summarize the classic and recent research on the one-stage revision.

Combined Techniques of Non-invasive 99mTcBesilesomab/ 99mTc-Sulfur Colloid with Hybrid SPECT/CT Imaging in Characterising Cellulitis from Symptomatic Perimegaprosthetic Infection: A Case Report

@#Megaprosthesis is used to restore the form and function of massive skeletal defects, but it is accompanied by risks of failure, mainly due to perimegaprosthetic infection (PMI). In practice, the diagnosis of infected megaprosthesis among patients with a high index of clinical suspicion, elevated serological markers, and multiple negative or inconclusive imaging can be very challenging and poses a diagnostic conundrum to many orthopaedic surgeons. We present the case of a symptomatic 26-year-old female with large B-cell lymphoma who developed cellulitis with suspected complication of PMI 15 months post-implantation. The combination of advanced nuclear medicine imaging strategies, i.e., 99mTc-besilesomab/ 99mTc-sulfur colloid scintigraphy with hybrid single-photon emission computed tomography/computed tomography (SPECT/CT) scanning helps to characterise and delineate both infections. Invasive procedures such as joint aspiration and biopsy were avoided, and the patient was successfully treated with antibiotics. Hence, we report a case where advanced imaging modalities were decisive in the investigation of PMI.

Relationship of pathogenic bacteria distribution with drug resistance and treatment cycle for periprosthetic joint infection after total joint arthroplasty / 中国组织工程研究

BACKGROUND: Understanding the characteristics of bacteriology in periprosthetic joint infection and choosing specific anti-infective drugs are very important to control the periprosthetic joint infection. The results of bacterial culture and antimicrobial susceptibility test can provide important reference for diagnosis and treatment. OBJECTIVE: To investigate the distribution and drug resistance of pathogenic bacteria in periprosthetic joint infection patients, and analyze the effect of bacterial culture results on the treatment period. METHODS: A retrospective analysis was conducted on 59 patients who underwent artificial joint revision between September 2015 and September 2019. The infection time, results of bacterial culture and antimicrobial susceptibility test, antibiotics application duration, prosthesis-free interval, total length of hospital stay from infection to renovation, recovery time of erythrocyte sedimentation rate and C-reactive protein were collected. The pathogenic bacteria distribution, drug resistance situation and the effect of the pathogenic bacteria and bacterial resistance on antibiotics application duration, prosthesis-free interval, and days in hospital were analyzed. RESULTS AND CONCLUSION: (1) Among the 59 patients with periprosthetic joint infection, there were 31 cases of hip joint and 28 cases of knee joint. The highest proportion of periprosthetic joint infection phase was delayed infection (49%). The pathogenic bacteria were cultured from 35 cases, and the positive rate of bacterial culture was 59%. (2) Among the cultured pathogens, staphylococcus aureus accounted for the highest proportion (29%). (3) The pathogenic bacteria of 18 patients were antibiotic resistant, and the drug resistance rate reached 51%. (4) The bacterial cultured negative group had longer prosthesis-free interval and longer recovery times of erythrocyte sedimentation rate and C-reactive protein than those of the positive group (P < 0.05). (5) Compared with the group with sensitive antibiotics, the duration of antibiotic application and recovery times of erythrocyte sedimentation rate and C-reactive protein were longer in the group with resistant antibiotics (P < 0.05). (6) In this study, the positive rate of bacterial culture in periprosthetic joint infection patients was not high, but the resistance rate of pathogenic bacteria was relatively high; the treatment period with positive pathogenic bacteria and sensitive antibiotics was shorter.

Underlying targets and mechanism of taohong siwu decoction in prosthetic joint infection on network pharmacology / 中国组织工程研究

BACKGROUND: Taohong Siwu Decoction has a good effect in the treatment of periprosthetic infection after joint replacement, and can improve the function of joint movement. However, most present studies focus on the antibacterial effect of single drug and its components in the prescription, and there is little research on the compound and other mechanisms. OBJECTIVE: To explore the mechanism of Taohong Siwu Decoction in the treatment of periprosthetic joint infection. METHODS: Ingredients and target genes of Semen Persicae, Carthami Flos, Rehmanniae Radix Praeparata, Paeoniae Radix Alba, Angelicae Sinensis Radixand and Chuanxiong Rhizoma were screened by Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. Periprosthetic joint infection-related target genes were obtained from the human gene database (GeneCards). Cytoscape3.7.2 was used for constructing a “Drug-Ingredient-Target-Disease” network. The key target genes were introduced into the STRING to construct protein-protein interaction network. We analyzed the mechanism by Kyoto Encyclopedia of Genes and Genomes and Gene Ontology biological enrichment analysis. RESULTS AND CONCLUSION: (1) Totally 15 active components, such as quercetin, luteolin and kaempferol, were screened from Taohong Siwu Decoction, which acted on 34 key genes, such as vascular endothelial growth factor A, tumor necrosis factor, and interleukin-6. (2) Gene Ontology function enrichment showed that the biological process and function of Taohong Siwu Decoction were concentrated in positive regulation of biological process, response to chemical stimulus, response to stress, and regulation of apoptosis. (3) Kyoto Encyclopedia of Genes and Genomes pathway enrichment showed that the treatment of periprosthetic joint infection by Taohong Siwu Decoction mainly involved pathways in cancer, AGE-RAGE signaling pathway, fluid shear stress and atherosclerosis, inflammatory bowel disease and cytokine-cytokine receptor interaction pathway. (4) Through the study of network pharmacology, it is found that Taohong Siwu Decoction could treat periprosthetic joint infection by inhibiting bacterial growth and improving hemorheology, which provided a preliminary theoretical basis for the application of “activating circulation and removing blood stasis” in periprosthetic joint infection and a new idea for subsequent experiments.

The Results of Two-stage Revision for Methicillin-resistant Periprosthetic Joint Infection (PJI) of the Hip

@#Introduction: Periprosthetic joint infection (PJI) of the hip due to methicillin-resistant bacteria is difficult to treat and remain a challenge for arthroplasty surgeon. Material and Methods: Retrospective review was done to the patients who received two-stage revisions with an antibiotic loaded cement-spacer for PJI of the hip between January 2010 to May 2015. We found 65 patients (65 hips) with positive culture findings. Eight patients were lost to follow-up and excluded from the study. Among the rest of the 57 patients, methicillin-resistant infection (MR Group) was found in 28 cases. We also evaluate the 29 other cases that caused by the other pathogen as control group. We compared all of the relevant medical records and the treatment outcomes between the two groups. Results:The mean of follow-up period was 33.7 months in the methicillin-resistant group and 28.4 months in the control group (p = 0.27). The causal pathogens in the methicillinresistant group were: Methicillin-resistant Staphylococcus aureus (MRSA) in 10 cases, Methicillin-resistant Staphylococcus epidermidis (MRSE) in 16 cases and Methicillin-resistant coagulase-negative Staphylococcus (MRCNS) in two cases. The reimplantation rate was 92.8% and 89.6% in the methicillin-resistant and control group, respectively (p= 0.66). The rates of recurrent infection after reimplantation were 23.1% (6/26) in the methicillin-resistant group and 7.6% (2/26) in the control group (p= 0.12). The overall infection control rate was 71.4% (20/28) and 89.6% (26/29) in the methicillin-resistant and control group, respectively (p = 0.08). Both groups showed comparable baseline data on mean age, BMI, gender distribution, preoperative ESR/CRP/WBC and comorbidities. Conclusions: Two-stage revision procedure resulted in low infection control rate and high infection recurrency rate for the treatment of methicillin-resistant periprosthetic joint infection (PJI) of the hip. Development of the treatment strategy is needed to improve the outcome of methicillin resistant periprosthetic joint infection (PJI) of the hip.

Treatment and influencing factors of infection after limb salvage surgery for malignant tumor around knee joint / 中国修复重建外科杂志

Objective: To summarize the experience in the treatment of infection after limb salvage surgery for malignant tumor around knee joint, and explore the risk factor related to infection after limb salvage surgery. Methods: A clinical data of 212 patients with malignant tumor around the knee joint underwent limb salvage surgery between January 2008 and December 2017 were retrospectively analyzed. Among them, 14 cases had infection after limb salvage surgery. Two cases of acute infection were treated with sensitive antibiotics; 12 cases of chronic infection were treated with debridement and antibiotic bone cement occupying device implantation in the first stage, and prosthesis revision (8 cases), knee joint fusion (2 cases), or amputation (2 cases) in the second stage after infection control. The age, gender, preoperative chemotherapy cycle, bone marrow suppression, serum albumin, hemoglobin, operation time, postoperative drainage time, and blood transfusion volume were analyzed to screen the risk factors related to infection after limb salvage surgery. The infection and tumor recurrence were observed, and the limb function was evaluated by Enneking scoring system. Results: The univariate analysis showed that the preoperative chemotherapy cycle, bone marrow suppression, operation time, and postoperative drainage time were the influencing factors of postoperative infection ( P<0.05). Multivariate analysis showed that the operation time, preoperative chemotherapy cycle, and postoperative drainage time were risk factors of postoperative infection ( P<0.05). Among the 14 patients, 1 patient died of traffic accident at 6 months after the second stage operation, and 13 patients were followed up 12.2-48.0 months (mean, 19.9 months). Two cases of acute infection cured. Among the 11 patients with chronic infection, 2 cases of subluxation of the antibiotic bone cement occupying device after the first stage operation occurred; 9 cases of infection cured and 2 cases recurred. At 12 months after operation, except 1 case died by accident, the Enneking scores of the other 13 patients were 12-26, with an average of 20. At last follow-up, 1 case of lung metastasis was still alive, and no tumor metastasis or recurrence was found in the rest. Conclusion: The time of limb salvage surgery, preoperative chemotherapy cycle, and drainage time after limb salvage surgery are the risk factors of infection after limb salvage surgery. Early etiological examination and drug sensitivity test is the key to the treatment of infection. One-stage debridement combined with antibiotic bone cement occupying device can effectively cure infection and save patients' limbs.

Distribution and drug resistance of pathogens causing periprosthetic infections after hip and knee arthroplasty / 中国骨伤

OBJECTIVE@#To study the distribution and drug resistance of pathogens causing periprosthetic infections after hip and knee arthroplasty, and to formulate prevention and treatment strategies for drug-resistant bacteria.@*METHODS@#The data of 146 cases of periprosthetic infection after primary hip and knee arthroplasty from 2010 to 2015 were collected, including 111 cases of periprosthetic infection after hip arthroplasty and 35 cases of periprosthetic infection after knee arthroplasty. The culture positive rate, pathogenic bacteria composition and drug resistance rate were counted over the years, and the change trend of pathogen distribution and drug resistance was analyzed.@*RESULTS@#One hundredand eight strains of pathogenic bacteria were detected in 146 cases, and the positive rate of culture was 73.97%. Gram positive bacteria accounted for 55.48%, Staphylococcus epidermidis and Staphylococcus aureus accounted for 25.34% and 15.07% respectively. Gram negative bacteria accounted for 13.01%, including Enterobacter cloacae, Pseudomonas aeruginosa and Escherichia coli. There were 4 cases of Mycobacterium tuberculosis infection and mixed infection. The results of culture over the years showed that the constituent ratio of Gram positive bacteria had an increasing trend, fluctuating from 39.13% to 76.47%. The results of drug sensitivity showed that the pathogens were highly resistant to β-lactams, quinolones, clindamycin and gentamicin, and the drug resistance rate was increasing, but it was still sensitive to rifampicin, nitrofurantoin, tigecycline, linezolid and vancomycin.@*CONCLUSION@#Gram positive bacteria are the main pathogens of periprosthetic infection, and the proportion is increasing gradually.The pathogens have high resistance to many kinds of antibiotics, and the resistance rate is still increasing. To strengthen the monitoring of the distribution and drug resistance of pathogenic bacteria is helpful to grasp its change trend and formulate targeted prevention and control strategies.

Advances on treatment of periprosthetic infection and antibiotic delivery system after total hip arthroplasty / 中国骨伤

Periprosthetic infection after hip replacement is a clinical catastrophic disease, which often leads to the failure of the prosthesis. It needs the combination of systemic antibiotics to cure the infection, which brings huge burden to doctors and patients. There are strict indications for debridement and one-stage revision of the prosthesis, and few cases meet the requirements. The second revision is still the gold standard for the treatment of periprosthetic infection. It is suitable for all infection conditions and has a high success rate. On the second phase of renovation, the antibiotic sustained release system plays a key role, and the carrier of antibiotic sustained-release system is the focus of current research, including classic bone cement and absorbable biomaterials. Bone cement has strong mechanical strength, but the antibiotic release shows a sharp decline trend; the absorbable biomaterials can continuously release antibiotics with high concentration, but the mechanical strength is poor, so it could not use alone. The combination of bone cement and absorbable biomaterials will be an ideal antibiotic carrier. PMMA is the most commonly used antibiotic carrier, but the antibiotic release concentration is decreased sharply after 24 hours. It will be difficult to control the infection and increase the risk of bacterial resistance if it is lower than the minimum inhibitory concentration. The biodegradable materials can release antibiotics completely, with long release time and high concentration, but low mechanical strength. Antibiotic spacer plays an important role in the control of infection. In the future, how to further extend the antibiotic release time of antibiotic sustained-release system, increase the amount of antibiotic release and maintain the mechanical strength of the material will be studied.

Utility of radiolabeled leukocyte and bone marrow scintigraphy with SPECT/CT in the diagnostic work-up- of the painful prosthetic joint: A single-institution experience

@#In tbhe assessment of prosthetic joint pains, differentiating between aseptic loosening and infection can be challenging due to their similarities in clinical presentation and histopathology. Combined radiolabeled leukocyte and bone marrow scintigraphy and SPECT/CT is considered the most suitable nuclear imaging modality for this purpose. However, this is infrequently performed in our local setting. We present two cases where these studies were appropriately performed with different scan outcomes. The first case involved a 67-year-old male with painful right knee prosthesis and an alleged history of recurrent periprosthetic joint infection (PJI). The leukocyte tagging scan and marrow scan images were found to be congruent, which was more compatible with aseptic loosening. No emergent surgical intervention was done in our hospital, and the patient returned to this home territory for further management. The second case was a 72-year-old male with progressive pain in his left prosthetic hiip which began after surgery a year prior. Scan images were incongruent, suggestive of PJI; this was confired on joint aspiration and eventual surgical revision. Despite this imaging study's high sensitvity and high specificity, it has not been well-received in management algorihms of PJI. Collaboration between clinicans and nuclear imaging specilists is key in increasing the general use of these procedures.

Analysis of risk factors related to periprosthetic infection after breast augmentation / 中国修复重建外科杂志

Objective: To explore the risk factors related to periprosthetic infection after breast augmentation, and to provide a basis for reducing the risk of postoperative infection. Methods: A total of 1 056 female patients who underwent breast augmentation between January 2010 and January 2018 were analyzed retrospectively. The patients were 20 to 44 years old (mean, 31.6 years). The body mass index (BMI) was 19.0-31.1 kg/m 2, with an average of 24.47 kg/m 2. According to the periprosthetic infection standard of the United States Centers for Disease Control and Prevention (CDC), the patients were divided into infection group and non-infection group. Age, BMI, diabetes, previous history of immunosuppression, history of smoking, previous history of breast surgery, previous history of mastitis, combined with active dermatitis, surgical approach, the type and shape of breast prosthesis, implant in the different layers, combined with mastopexy, operation time, postoperative antibiotic time, postoperative breast crash, and postoperative potential infection surgery were analyzed by univariate analysis. The influencing factors of prosthetic infection were screened by logistic regression. Results: Periprosthetic infection occurred in 60 cases after operation, and the infection rate was 5.68%. Among them, 11 cases were acute infection, 33 cases were subacute infection, 16 cases were delayed infection, and 20 cases were positive in bacterial culture. Postoperative breast crash occurred in 114 cases. Univariate analysis showed that diabetes, previous history of immunosuppression, history of smoking, previous history of mastitis, postoperative breast crash, postoperative potential infection surgery, and combined with breast suspension were the influencing factors of postoperative periprosthetic infection ( P<0.05). Multivariate analysis showed that diabetes, history of smoking, and postoperative breast crash were the risk factors of periprosthetic infection ( P<0.05). Conclusion: Diabetes, smoking, and postoperative breast crash are the risk factors of periprosthetic infection after breast augmentation.

Esterasa leucocitaria como prueba diagnóstica ante un proceso infeccioso articular de rodilla / Leukocyte esterase as a diagnostic tool for an infectious disease of the knee

Resumen: Antecedentes: La infección articular es un reto ortopédico por su complejidad diagnóstica y efectos devastadores al no tratarse oportunamente. Contamos con diversos estudios de diagnóstico: cultivo, VSG, PCR, conteo de leucocitos, entre otros, pero ninguno es preciso, tardan más de 30 minutos en realizarse y requieren de infraestructura compleja. En este estudio determinamos la sensibilidad y especificidad de la esterasa leucocitaria para la detección de un proceso infeccioso articular en población mexicana. Material y métodos: Durante Noviembre de 2015 a Abril de 2016, se obtuvo líquido sinovial de pacientes con diagnóstico de infección articular con o sin implante, y de otros sin infección, con patología degenerativa de rodilla. Se evaluó la muestra mediante el test de esterasa leucocitaria COMBI-SCREEN 11SYS con lectura colorimétrica a los dos minutos; se determinó positivo para infección con dos cruces; el resto de la muestra fue enviado a cultivo. Resultados: Realizamos el test en 64 muestras de líquido sinovial de rodilla, 19 diagnosticadas con infección articular y 45 sin infección. Se obtuvo una sensibilidad de 100%, especificidad de 88.24%, VPP de 68.42% y VPN de 100%; índice de Kappa de .753. Conclusiones: La esterasa leucocitaria es una prueba eficaz para detectar un proceso infeccioso contra uno inflamatorio con alta probabilidad de acierto. Este estudio presentó un índice de concordancia Kappa de 0.753, con lo que demostró ser reproducible, por lo que recomendamos implementarlo en los servicios de urgencias a nivel nacional.

Abstract: Background: Articular infection is an orthopedic challenge due to its difficult diagnosis and devastating results. Various diagnostic studies exist: culture, ESR, CRP, count of leukocytes, among others, but none is specific, they all take more than 30 minutes to complete, and require complex infrastructure. In this study, we determine the sensitivity and specificity of the leukocyte esterase for detection of an infectious process joint in Mexican population. Material and methods: During November 2015 to April 2016, we obtained synovial fluid from two groups of patients: one with a diagnosis of synovial joint infection with or without implant, and the control group, without infection but with degenerative pathology of the knee. We evaluated the sample using the leukocyte esterase test COMBI-SCREEN 11SYS with colorimetric reading at two minutes; two crosses determined positive for infection; the remainder of the sample was sent for culture. Results: We performed the test in 64 samples of synovial fluid, 19 diagnosed with articular infection and 45 without it. We obtained a sensitivity of 100%, specificity of 88.24%, PPV of 68.42%, and NPV of 100%; Kappa index of .753. Conclusions: Leukocyte esterase is an effective test to detect an infectious process against an inflammatory one with a high probability of success. This study presented an index of agreement Kappa of 0.753, proving to be reproducible.

Tratamiento para artroplastías totales de cadera infectadas: 3 tiempos quirúrgicos en un período de hospitalización (técnica T-3/1) / Treatment of the infected Hip replacement: 3 surgical times in one hospital stay (T-3/1)

Resumen: Antecedentes: El impacto de una infección articular periprotésica crónica, la variabilidad en los índices de recidiva y la falta de consenso en cuanto a cuál es la mejor forma para tratarla obligan a buscar alternativas. ¿Tiene la alternativa aquí propuesta una tasa de recidiva al menos igual o menor que los métodos ahora usados? Material y métodos: Se estudiaron retrospectivamente 15 pacientes adultos. Analizamos variables relacionadas con el huésped, implante, germen, diagnóstico y la tasa de recidiva. Se describe el protocolo de tratamiento y la técnica quirúrgica. Resultados: De los 15 pacientes uno se perdió cuando cumplió 48 meses de seguimiento. En otro se retiró definitivamente el implante. Dos fallecieron a los 36 y 40 meses después del recambio y en uno había duda de reinfección. Tres presentaron recidiva y fueron reintervenidos con la misma técnica. Al final del seguimiento 100% de los pacientes vivos se encontraban asintomáticos. Conclusiones: La técnica T-3 en 1 (3 tiempos quirúrgicos en un solo período de hospitalización) ofrece resultados comparables con los índices de éxito en recambios en uno o dos tiempos. La principal ventaja es que hay una mayor seguridad de haber efectuado una limpieza efectiva, lo que permite iniciar una rehabilitación inmediata sin tener que esperar semanas o meses para un reimplante definitivo como en el recambio en dos tiempos. Cada paciente debe tratarse en forma individual según los factores de riesgo de recidiva y las recomendaciones por parte de los paneles de expertos. Se propone una Tabla de decisiones para prescribir las técnicas de erradicación actualmente disponibles.

Abstract: Background: The impacts of chronic periprosthetic joint infection, variability in rates of recurrence and the lack of consensus as to what is the best way to treat it, require using alternatives. Does the alternative proposed here has a recurrence rate at least equal to or less than the methods used now? Material and methods: We were retrospectively studied 15 adult patients and analyze variables related to the host, implant, germ, diagnosis and recurrence rate. The surgical technique treatment protocol it's described. Results: Of the 15 patients, one was lost when he was 48 months follow up. In another the implant is definitely retreat. 2 died at 36 and 40 months after the replacement, there was doubt one of reinfection. Three recurred and were re-operated with the same technique. At follow-up cut, 100% of living patients are asymptomatic with out recurrence. Conclusions: The T-3 in 1 surgical technic (three times in one period of hospitalization) provides comparable results with success rates in one or two times. The main advantage is that there is greater confidence that you have making effective cleaning, launch an immediate rehabilitation, without having to wait weeks or months for a definitive reimplantation as 2 times replacement. Each patient should be treated individually according to risk factors of recurrence and recommendations made by expert panels. A decision table is proposed to prescribe eradication techniques currently available.

Agentes etiológicos más frecuentes en infecciones periprotésicas de artroplastía primaria de rodilla y cadera en adultos mayores / Etiological agents more common in primary hip and knee joint replacement infections in older adults

Resumen: Antecedentes: Los agentes etiológicos más frecuentes en las infecciones periprotésicas son Escherichia coli y Staphylococcus aureus. La frecuencia de estas infecciones se presenta en el reemplazo articular de rodilla de 0.68 a 1.60% en comparación con el de cadera de 0.67 a 2.4%. Objetivo: identificar cuáles son los agentes etiológicos más frecuentes en infecciones periprotésicas en adultos mayores y en pacientes con cirugía primaria de cadera y rodilla. Material y métodos: Se realizó un estudio observacional, transversal y retrospectivo, tipo serie de casos en un período comprendido de Junio de 2011 a Diciembre de 2014, se incluyeron pacientes mayores de 60 años con diagnóstico de infección periprotésica mediante dos cultivos positivos con antibiograma. Resultados: Se evaluaron 62 pacientes, 59.7% presentaron infecciones de rodilla y 40.3% de cadera, 59% fueron infecciones por Escherichia coli y 22% por Staphylococcus aureus. El antibiótico que mejor sensibilidad reportó fue trimetoprim-sulfametoxazol (40.3% )y el de mayor resistencia fue penicilina G (32.2%). Conclusión: Los agentes etiológicos más frecuentes fueron Escherichia coli y Staphylococcus aureus.

Abstract: Background: The most common etiological agents in periprosthetic infections are Escherichia coli and Staphylococcus aureus. The frequency of these infections are found in knee replacement with 0.68 to 1.60% compared to the hip with 0.67 to 2.4%. Objective: To identify what are the most common etiologic agents in periprosthetic infections in elderly patients with primary hip and knee surgery. Material and methods: An observational study, transverse and retrospective case series was performed in a period from June 2011 to December 2014, patients over 60 years with a diagnosis of periprosthetic infection by two positive cultures with antibiograma. Results: 62 patients were evaluated 59.7% were infections of knee and hip 40.3%, 59% were infections by Escherichia coli and Staphylococcus aureus 22%. The best sensitivity reported antibiotic trimethoprim-sulfamethoxazole was 40.3%. The largest penicillin G resistance 32.2%. Conclusion: The most common causative agents were Escherichia coli and Staphylococcus aureus.