Microbiological Profi le of Periprosthetic Knee Infections in a Brazilian Unified Health System Hospital Specialized in Highly Complex Orthopedic Surgeries / Perfil microbiológico das infecções periprotéticas do joelho em um hospital do Sistema Único de Saúde especializado em cirurgias ortopédicas de alta complexidade

Abstract Objective We studied the microbiological profile of periprosthetic knee infections treated in a Brazilian tertiary hospital. Methods The study included all patients undergoing revision surgery for total knee arthroplasty (RTKA) between November 2019 and December 2021, with a diagnosis of periprosthetic infection confirmed per the 2018 International Consensus Meeting (ICM) criteria. Results Sixty-two patients had a periprosthetic joint infection (PJI) per the 2018 ICM criteria. Cultures were monomicrobial in 79% and polymicrobial in 21% of cases. The most frequent bacterium in microbiological tissue and synovial fluid cultures was Staphylococcus aureus, observed in 26% of PJI patients. Periprosthetic joint infection with negative cultures occurred in 23% of patients. Conclusion Our results show the following: i) a high prevalence of Staphylococcus as an etiological agent for knee PJI; ii) a high incidence of polymicrobial infections in early infections; iii) the occurrence of PJI with negative cultures in approximately one fourth of the subjects.

Resumo Objetivo Identificar o perfil microbiológico das infecções periprotéticas do joelho tratadas em um hospital terciário brasileiro. Métodos Todos os pacientes submetidos à cirurgia de revisão de artroplastia total do joelho (RATJ), no período compreendido entre novembro de 2019 e dezembro de 2021, e que tiveram o diagnóstico de infecção periprotética confirmado de acordo com critérios do International Consensus Meeting (ICM) 2018, foram incluídos no estudo. Resultados Sessenta e dois pacientes foram diagnosticados com infecção periprotética (IAP) pelos critérios do International Consensus Meeting 2018. Culturas monomicrobianas foram identificadas em 79% e polimicrobianas em 21% dos casos. A bactéria mais frequentemente identificada nas culturas microbiológicas de tecidos e líquido sinovial foi o Staphylococcus aureus, presente em 26% dos pacientes com infecção periprotética. Infecções periprotéticas com culturas negativas ocorreram em 23% dos pacientes. Conclusão Nossos resultados evidenciam: i) alta prevalência de bactérias do gênero Staphylococcus como causadores da IAP do joelho; ii) a alta incidência de infecções polimicrobianas nas infecções precoces e iii) IAP com culturas negativas ocorre em, aproximadamente, um quarto dos pacientes.

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.

Profilaxis antibiótica extendida para pacientes sometidos a una artroplastia de cadera primaria: ¿disminuye el riesgo de infecciones periprotésicas? / Extended oral antibiotic prophylaxis in primary hip arthroplasty: Does it decrease periprosthetic joint Infections?

Introducción: La prevalencia de infecciones periprotésicas luego de una artroplastia total de cadera primaria es aproximadamente del 2%. El objetivo de este estudio fue determinar si existen diferencias estadísticamente significativas entre la tasa de infeccio-nes periprotésicas agudas ante una profilaxis antibiótica extendida (7 días) y una profilaxis antibiótica estándar (24 h). Materiales y Métodos: Se realizó un estudio clínico prospectivo, entre julio de 2021 y mayo de 2022, que incluyó a 28 adultos con fractura de cadera sometidos a una artroplastia primaria que recibieron profilaxis antibiótica con cefalosporinas de primera generación durante 7 días a quienes se comparó con 95 adultos con fracturas de cadera con una artroplastia primaria y profilaxis antibiótica de 24 h, extraídos de una base de datos secundaria del registro del hospital. Resultados: La tasa de infecciones periprotésicas agudas fue del 10,71% en el grupo con profilaxis extendida y del 17,89% en quienes recibieron profilaxis estándar, sin diferencias estadísticamente significativas (p = 0,36). Conclusiones: Si bien, según la bibliografía disponible, la prolongación de la profilaxis antibiótica puede ser una medida simple, segura y rentable para contrarrestar los factores no modificables del paciente y así reducir las infecciones periprotésicas; en este estudio, no se demostró que la profilaxis antibiótica extendida disminuya la tasa de infecciones periprotésicas agudas a los 30 días en pacientes con artroplastias de cadera primarias. Nivel de Evidencia: II

Introduction: The prevalence of periprosthetic infections (PPIs) after primary total hip arthroplasty (THA) is approximately 2%. The objective of this study is to determine if there are statistically significant differences between the proportion of acute PPIs with extended oral antibiotic prophylaxis (7 days) vs standard oral antibiotic prophylaxis (24 hours). Materials and Methods: A prospective clinical trial was conducted between July 2021 and May 2022. A total of 28 adult patients with hip fracture underwent a primary arthroplasty and received extended oral antibiotic (EOA) prophylaxis for 7 days with first-generation cephalosporins. They were compared to a secondary database of the hospital registry, which included a total of 95 adult patients with hip fractures who underwent primary arthroplasty and received a standard oral antibiotic (SOA) prophylaxis for 24 hs. Results: In the EOA group, the rate of acute PPI was 10.71%, while in the SOA group it was 17.89%. When comparing the rate in both groups, no statistically significant differences were found (p=0.36). Conclusions: Although the available literature suggests that extended antibiotic prophylaxis can be a simple, safe, and cost-effective measure to counteract the patient's non-modifiable factors and thus reduce periprosthetic infections, our study found no evidence that it reduces the proportion of acute PPI at 30 days in primary hip arthroplasties. Level of Evidence: II

Conservación de tallos femorales no cementados fijos en pacientes con infección periprotésica crónica de cadera / Preservation of fixed cementless femoral stems in patients with chronic periprosthetic hip Infection

Introducción: La revisión en dos tiempos se considera el método de referencia para tratar a pacientes con artroplastia de cadera e infección crónica. Sin embargo, durante el retiro de un vástago femoral no cementado fijo, se puede dañar el fémur proximal, lo que puede plantear dificultades en el reimplante. Objetivo: Determinar si la infección periprotésica crónica de cadera se puede tratar con un intercambio parcial de sus componentes, conservando un vástago femoral no cementado fijo. materiales y métodos:Estudio de serie de casos retrospectivo, multicéntrico que incluyó a 9 pacientes con artroplastia de cadera e infección crónica, programados para el recambio parcial en uno o dos tiempos con retención del tallo femoral fijo, entre enero de 2014 y noviembre de 2019. Se evaluó la evolución mediante el examen clínico, el puntaje de cadera de Harris, y estudios de laboratorio y radiológicos. Resultados: En un seguimiento medio de 5.8 años de 9 pacientes con artroplastia de cadera no cementada, después del reimplante de la prótesis, la infección remitió en 8 pacientes (88,9%), y el puntaje medio de cadera de Harris fue de 81 en el último control. No hubo aflojamiento de componentes acetabulares ni femorales. Conclusiones: La conservación de vástagos femorales no cementados puede representar una opción aceptable para los pacientes con infección periprotésica crónica de cadera cuando la extracción del componente femoral daría como resultado una pérdida significativa de hueso y un compromiso de la reconstrucción. Sin embargo, se requieren más estudios sobre esta técnica. Nivel de Evidencia: IV

Introduction: Two-stage revision is considered the gold standard for the treatment of chronically infected hip arthroplasty. However, during the removal of a fixed cementless femoral stem, the proximal femur can be damaged, which can lead to difficulties in reimplantation. Objective: We intend to determine if chronic periprosthetic hip infection can be treated with a partial exchange of its components, in two stages, keeping a fixed cementless femoral stem. materials and methods: This retrospective, multicenter case series study included 9 patients with chronic infection following hip arthroplasty, scheduled for single- or two-stage partial exchange with retention of the fixed femoral stem between January 2014 and November 2019. We assessed the patients' progress through clinical examination, Harris Hip Score evaluation, and laboratory and radiological studies. Results: In a mean follow-up of 5.8 years in 9 patients with cementless hip arthroplasty, 8 patients achieved infection remission (88.9%) after prosthetic reimplantation, and the mean Harris Hip Score reached 81 points at the last follow-up evaluation. There was no loosening of acetabular or femoral components. Conclusions: Uncemented femoral stem retention may represent an acceptable option for patients with chronic periprosthetic hip infection when removal of the femoral component would result in significant bone loss and compromise of the reconstruction. However, more studies are required on this treatment. Level of Evidence: IV

Seudotumor infectado en un paciente con artroplastia de cadera con par de fricción metal-metal / Infected pseudotumour in total hip arthroplasty with metal-on-metal friction couple

La artroplastia total de cadera es el principal tratamiento para la artrosis avanzada de cadera y las complicaciones pueden ser luxación, infección, aflojamiento aséptico y, en menor medida, reacciones adversas al metal. El seudotumor es una complicación poco frecuente con un par de fricción metal-metal. El diagnóstico y el tratamiento correctos son muy importantes para disminuir la morbimortalidad. Presentamos el caso de un hombre de 63 años que había sido sometido a una artroplastia total de cadera con un par de fricción metal-metal, 13 años atrás. Al consultar, tenía una gran masa en el glúteo derecho y parestesias en el territorio ciático homolateral. Se diagnosticó seudotumor asociado a infección periprotésica y el tratamiento definitivo consistió en revisión en un tiempo y la administración de antibióticos. Nivel de Evidencia: IV

Total hip arthroplasty (THA) is the main treatment for advanced hip osteoarthritis and its complications include dislocation, infec-tion, aseptic loosening and, to a lesser extent, adverse reactions to metal. Pseudotumor is a rare complication of THA with a metal-on-metal friction couple; its diagnosis and treatment are extremely important to reduce morbidity and mortality. We present the case of a 63-year-old male patient with a 13-year history of THA with a metal-on-metal friction couple who, at the time of con-sultation, presented a large palpable mass in the right gluteus and paresthesias in the homolateral sciatic nerve. The diagnosis of an infected pseudotumor was reached and treated with hip revision and antibiotic therapy. Level of Evidence: IV

Microbiología de las infecciones periprotésicas de rodilla en Hospital Regional de Talca / Microbiology of periprosthetic knee infections in Regional Hospital

Introduction: Periprosthetic infection (PPI) is one of the most devastating complications of total knee arthroplasty (TKA). The incidence described in the literature is 2.4% and the most frequently isolated bacteria are Staphylococcus Aureus and Staphylococcus Coagulase-Negative (Gram positive). Polymicrobial infections represent between 10 to 37% and negative cultures between 7 to 15%. Methodology: Descriptive and retrospective study that consisted of reviewing the TKA database of the Regional Hospital of Talca during the 2018-2020 period, where knee PPIs were identified according to the diagnostic criteria validated in 2018. The cultures of patients diagnosed with PPI were reviewed, analyzing the antibiogram and resistance profile. Results: During 2018-2020, 459 TKAs were performed in our center, diagnosing 30 PPIs of the knee. 47% of PPIs were acute and 53% chronic. The results of the cultures were negative in 26.6%, 23.3% Methicillin Sensitive Staphylococcus Aureus; 13.3% Methicillin Resistant Staphylococcus Epidermidis and 13.3% of the cultures were polymicrobial. Discussion: Highlights the high resistance to methicillin, especially of Staphylococcus Epidermidis. This opportunistic pathogen has the ability to form a biofilm and, thanks to its genomic flexibility, rapidly acquires resistance to antibiotics. Polymicrobial infections have a synergistic effect that favors the persistence of the infection, which is why they will require a greater number of surgeries and prolonged antibiotic therapy. Pruebas especiales como la sonicación podrían aumentar las posibilidad de identificar al microorganismo. Conclusion: In these three years of follow-up, the PPI rate has been higher than reported annually in the literature. Gram-positive microorganisms continue to predominate, but with an increase in the rate of resistant to methicillin. Also, highlight the number of negative cultures. There would be a possible benefit theoretical in optimizing antibiotic prophylaxis in view of the large percentage of methicillin resistance and in seeking new ways to reduce negative cultures.

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

Lavado con povidona yodada diluida en el reemplazo articular de cadera y rodilla para prevenir infecciones: estudio retrospectivo comparativo / Diluted povidone-iodine lavage in total hip and knee replacement: A retrospective comparative study

Introducción: Una de las medidas profilácticas para disminuir la incidencia de infecciones periprotésicas es el lavado con povidona yodada diluida, un agente con acción bactericida contra distintos microorganismos. El propósito de este estudio fue evaluar la incidencia de infecciones periprotésicas dentro de los primeros 90 días, en pacientes a quienes se les realizó un lavado con povidona yodada luego de implantar los componentes protésicos y antes del cierre de la herida. materiales y métodos: Se llevó a cabo un análisis retrospectivo comparativo de pacientes sometidos a artroplastias primarias de cadera y rodilla por artrosis y se comparó la incidencia de infecciones periprotésicas dentro de los primeros 90 días posoperatorios, entre pacientes que fueron operados antes de la introducción del lavado con povidona yodada y luego con su uso rutinario. Resultados: Se realizaron 643 (47,60%) reemplazos de rodilla y 708 (52,40%) reemplazos de cadera. Al comparar la incidencia de infecciones periprotésicas entre ambos grupos, no se observaron diferencias estadísticamente significativas (0,92% vs. 0,21%; p = 0,11). Sin embargo, se incrementó el riesgo de infección en los primeros 90 días posteriores a la cirugía (OR = 4,5; IC95% 0,56-36,19) cuando no se utilizó la solución. Conclusiones: El riesgo de desarrollar infecciones periprotésicas se incrementó 4,5 veces al realizar una artroplastia sin irrigación con povidona yodada diluida. Sin embargo, no se pudo demostrar que esto fuese estadísticamente significativo. Nivel de Evidencia: III

Introduction: One of the prophylactic techniques to reduce the incidence of periprosthetic infections is dilute povidone-iodine lavage, an agent with bactericidal action against different microorganisms. The purpose of this study was to evaluate the incidence of periprosthetic infections within the first 90 days in patients who had undergone povidone-iodine lavage after implantation of prosthetic components and before wound closure. Materials and methods: A comparative retrospective study was performed on patients who had undergone primary total hip or knee replacement due to advanced joint osteoarthritis between October 1999 and April 2020. We assessed the PJI rate between two cohorts: Group A, which consisted of patients who received povidone-iodine lavage routinely, and Group B, where this solution was not applied. Results: 643 (47.60%) knee replacements and 708 (52.40%) hip replacements were performed. When comparing the incidence of periprosthetic infections between both groups, no statistically significant differences were observed (0.92% vs. 0.21%; p = 0.11). However, the risk of infection was increased in the first 90 days after surgery (OR = 4.5; 95% CI 0.56-36.19) when the solution was not used. Conclusions: The risk of developing periprosthetic infections increased 4.5 times when performing an arthroplasty without irrigation with diluted povidone-iodine. However, this could not be shown to be statistically significant. Level of Evidence: III

Secuenciación de próxima generación para la detección de patógenos en cirugía de cadera: experiencia y viabilidad diagnóstica en un centro de atención terciaria de la Argentina / Next generation sequencing for the detection of pathogens in hip surgery. Experience and diagnostic feasibility in a tertiary care center in Argentina

Introducción: El diagnóstico rápido y definitivo con identificación del patógeno es fundamental cuando hay una infección periprotésica. La secuenciación de próxima generación permite identificar el ADN en un germen determinado en poco tiempo. Hasta donde sabemos, no hay reportes sobre su empleo para el manejo de la infección periprotésica en Sudamérica. Nuestro objetivo fue demostrar la viabilidad diagnóstica de las muestras obtenidas de una serie de pacientes operados en Buenos Aires, Argentina, y analizadas con la técnica de secuenciación de próxima generación. materiales y métodos: Se analizó a una serie prospectiva de 20 pacientes sometidos a cirugía de revisión séptica y aséptica de cadera desde diciembre de 2019 hasta marzo de 2020. Se obtuvieron muestras intraoperatorias de líquido sinovial, tejido profundo y canal endomedular, que fueron enviadas para su análisis al laboratorio NexGen Microgen. Resultados: Se seleccionaron 17 pacientes, porque tenían una muestra apta para analizar. Los resultados se recibieron dentro de las 72 h de la cirugía. En un caso, el resultado de la secuenciación de próxima generación informó un germen distinto del identificado en los cultivos posoperatorios de partes blandas, esto permitió corregir la antibioticoterapia. En otro, esta técnica identificó Parabacteroides gordonii en una revisión aséptica, en otro, Morganella morganii, a partir de cultivos negativos en una revisión en un tiempo. Conclusión: Se demostró la viabilidad diagnóstica con la secuenciación de próxima generación, se pueden obtener resultados de microorganismos patógenos dentro de las 72 h posteriores a la cirugía en pacientes con infección periprotésica y cultivos negativos. Nivel de Evidencia: IV

Introduction: Early diagnosis of a periprosthetic joint infection (PJI) and identification of the pathogen are paramount. Next-generation sequencing (NGS) can identify the nucleic acids in a given germ in a short period. To our knowledge, there are no reports of its use in the management of PJI in South America. Our objective was to demonstrate the diagnostic feasibility of the NGS technique on the samples obtained from a series of patients operated on in Buenos Aires, Argentina. Materials and methods: A prospective series of 20 patients undergoing septic and aseptic hip revision surgery from December 2019 to March 2020 was analyzed. Intraoperative samples of synovial fluid, deep tissue, and intramedullary canal were obtained and sent to the NexGen Microgen laboratory (Texas, USA) for analysis. Results: Seventeen patients were finally eligible to present a sample suitable for analysis. In 100% of the samples, NGS results were obtained within 72 hours of surgery. In one case, the NGS result reported a germ different from the one identified in the postoperative soft tissue cultures, allowing antibiotic therapy to be corrected. In another case, NGS identified Parabacteroides gordonii in aseptic revision surgery. In another patient, the NGS identified Morganella morganii, in which conventional postoperative cultures were negative in single-stage revision surgery. Conclusion: In this study, we demonstrated the diagnostic feasibility of NGS, obtaining results within 72 hours immediately after surgery for pathogenic organisms in patients with PJI and negative cultures. Level of Evidence: IV

Prevalencia y resultados de cultivos positivos inesperados en revisiones de reemplazo total de cadera presumiblemente asépticas / Prevalence and outcomes of unexpected positive cultures in presumed aseptic revision total hip arthroplasty

Introducción: Las tasas de infección periprotésica, a veces, son subestimadas, ya que muchos casos de presunta falla aséptica pueden deberse a una infección no reconocida. Los objetivos de este estudio fueron: 1) estimar la prevalencia de cultivos positivos intraoperatorios inesperados, 2) determinar si las comorbilidades o los factores de riesgo de los pacientes tuvieron relación con la presencia de cultivos positivos inesperados, 3) determinar la supervivencia del implante en un seguimiento mínimo de 12 meses. Materiales y Métodos: Se realizó un estudio retrospectivo y observacional. En las historias clínicas electrónicas, se identificaron todas las revisiones de artroplastia total de cadera de una única institución entre 2014 y 2021. Resultados: De las 49 revisiones de artroplastia total de cadera en un tiempo, 9 pacientes (18,4%) tuvieron un resultado positivo inesperado. Los microorganismos aislados fueron: Staphylococcus aureus (3), Pseudomonas aeruginosa (1), Staphylococcus lugdunensis (1), Staphylococcus epidermidis (2), Staphylococcus haemolyticus (1), Streptococcus epidermidis (1). Ninguna comorbilidad tuvo significancia estadística para favorecer cultivos positivos inesperados en las revisiones asépticas. El 2% de la muestra, con un período de seguimiento de 49 meses, se reinfectó. Conclusiones: Nuestro estudio arrojó una prevalencia de cultivos positivos inesperados del 18,4%. Ninguno de los factores de riesgo reportados en la bibliografía se asoció con un mayor riesgo de cultivos positivos inesperados, excepto los niveles altos de velocidad de sedimentación glomerular. Nuestros hallazgos son compatibles con los publicados y sugieren que los cultivos positivos inesperados en revisiones presumiblemente asépticas no tienen consecuencias significativas en la supervivencia del implante. Nivel de Evidencia: III

Introduction: Periprosthetic infection rates are sometimes underestimated, given that many cases of presumed aseptic failure may be due to unrecognized infection. The objectives of this study were: (1) to estimate the prevalence of unexpected positive intraoperative cultures; (2) to determine if any of the patient's comorbidities or risk factors were related to the presence of unexpected positive cultures; (3) to determine the implant survival during a follow-up of at least 12 months. Materials and Methods: A retrospective and observational study was carried out where, through electronic medical records, all revision total hip arthroplasties (THAs) from a single institution between 2014 and 2021 were identified. Results: Out of 49 single-stage revision THAs, 9 patients (18.4%) had an unexpected positive culture. The isolated microorganisms were Staphylococcus aureus (3), Pseudomonas aeruginosa (1), Staphylococcus lugdunensis (1), Staphylococcus epidermidis (2), Staphylococcus haemolyticus (1), Streptococcus epidermidis (1). In addition, when we evaluated the comorbidities of the patients, none had statistical significance in favoring unexpected positive cultures in aseptic revisions. We discovered that 2% of our sample with a follow-up period of 49 months developed reinfection. Conclusion: Our study showed a prevalence of unexpected positive cultures of 18.4%. None of the risk factors reported in the literature was associated with a higher risk of unexpected positive cultures, except for high ESR values. Our findings in the analyzed sample suggest that unexpected positive cultures in presumably aseptic revisions do not have significant consequences on implant survival, as found in the literature. Level of Evidence: III

Tratamento híbrido para revascularização de membro inferior em paciente com infecção de prótese vascular: relato de caso / Hybrid treatment for lower limb revascularization in a patient with vascular graft infection: a case report

Resumo Pacientes portadores de doença arterial obstrutiva periférica com isquemia crítica do membro associada a infecção de prótese vascular apresentam elevadas taxas morbimortalidade e alto risco de perda do membro. Apresentamos o caso de um paciente masculino de 76 anos com isquemia crítica do membro inferior esquerdo associada a infecção de prótese vascular femoropoplítea. Utilizamos abordagem híbrida para o tratamento com acesso cirúrgico das regiões inguinais e poplíteas, sendo a prótese vascular utilizada como acesso endovascular para recanalização direta da artéria femoral superficial devido a obstrução longa e extensa calcificação, que impediram as tentativas iniciais de tratamento endovascular. Após a recanalização endovascular, a prótese infectada foi retirada. O avanço das técnicas e materiais endovasculares em associação com a cirurgia aberta permitem novas soluções para pacientes quando os procedimentos habituais falham.

Abstract Patients with severe arterial obstructive disease and critical limb ischemia associated with vascular graft infection have elevated morbidity and mortality rates and are at high risk of limb loss. We present the case of a 76-year-old male patient with left lower limb critical ischemia and a femoropopliteal vascular graft infection. We used a hybrid treatment approach with an open surgical approach to the inguinal and popliteal regions and used the vascular prosthesis as endovascular access for direct recanalization of the superficial femoral artery, because the long occlusion and extensive calcification had frustrated initial attempts at endovascular treatment. After endovascular recanalization, the infected graft was removed. Used in conjunction with open surgery, advances in endovascular techniques and materials offer new solutions for patients when usual procedures fail.

Fungal periprosthetic joint infection: Rare but challenging problem / 中华创伤杂志(英文版)

Periprosthetic joint infection (PJI) is the most difficult complication following total joint arthroplasty. Most of the etiological strains, accounting for over 98% of PJI, are bacterial species, with Staphylococcusaureus and Coagulase-negative staphylococci present in between 50% and 60% of all PJIs. Fungi, though rare, can also cause PJI in 1%-2% of cases and can be challenging to manage. The management of this uncommon but complex condition is challenging due to the absence of a consistent algorithm. Diagnosis of fungal PJI is difficult as isolation of the organisms by traditional culture may take a long time, and some of the culture-negative PJI can be caused by fungal organisms. In recent years, the introduction of next-generation sequencing has provided opportunity for isolation of the infective organisms in culture-negative PJI cases. The suggested treatment is based on consensus and includes operative and non-operative measures. Two-stage revision surgery is the most reliable surgical option for chronic PJI caused by fungi. Pharmacological therapy with antifungal agents is required for a long period of time with antibiotics and included to cover superinfections with bacterial species. The aim of this review article is to report the most up-to-date information on the diagnosis and treatment of fungal PJI with the intention of providing clear guidance to clinicians, researchers and surgeons.

Mixed bacterial-fungal infection following total hip arthroplasty: A case report / 中华创伤杂志(英文版)

Prosthetic infection is one of the severe postoperative complications of arthroplasty. Mixed bacterial-fungal prosthetic infection is rare but can be disastrous. This case was a 76-year-old female suffered from prosthetic infection following total hip replacement due to femoral neck fracture and underwent multiple debridements. The culture of periprosthetic tissue was bacteriologically sterile following the first debridement, while the Staphylococcus hominis was identified in the second debridement in the previous hospitalization where fungal infection had not been considered. Thus the pathogen spectrum of anti-infection therapy failed to contain fungus. Ultimately, the culture result of our sampled periprosthetic tissue during the third debridement was Candida albicans without bacterium in our hospital. The fungal prosthetic infection was successfully treated by a two-stage revision with antifungal drugs. Accurate diagnosis and standardized treatment is the key to the therapy of infection after hip arthroplasty, especially for mixed bacterial-fungal prosthetic infection.

Aortic Root Replacement for Destructive Endocarditis - Clinic and Microbiology

Abstract Introduction: Destructive aortic root endocarditis is associated with high mortality rates. The objective of this article was to characterize the clinical and microbiological profiles of these patients, especially concerning an already implanted aortic valve prosthesis. We also focused on prognostic factors. Methods: Eighty patients underwent aortic root replacement due to destructive endocarditis from 1999 to 2018 in our institution. We analyzed their pre, intra, and postoperative data, outcomes, and predictors of mortality. Results: Thirty-one patients had native valve endocarditis (NVE), eight patients had early-onset prosthetic valve endocarditis (PVE), and 41 patients had late-onset PVE. Streptococcus was found in 19.4% of NVE cases and no PVE case. Coagulase-negative Staphylococcus was responsible for 62.5% of the cases of early-onset PVE. Thirty-four (42.5%) patients had received inappropriate antibiotics before admission. No microorganism was associated with higher risk of mortality. Aortoventricular dehiscence was identified as an independent risk factor of mortality along with PVE, concomitant bypass surgery, and delayed diagnosis. The incidence of postoperative complications was similar in all three groups. Rates of long-term survival (P=0.044) and freedom from the composite endpoint (P=0.024) defined as death, stroke, aortic valve reinfection, and aortic valve reoperation were the lowest within the NVE group and the highest among the PVE patients. Conclusion: In endocarditis, prolonged diagnostics, inadequate antimicrobial treatment, and late surgery led to destructive local complications and worsened the prognosis. PVE is associated with higher mortality than NVE.

Tratamiento quirúrgico de la endocarditis infecciosa activa / Active infective endocarditis: surgical treatment

Resumen: La endocarditis infecciosa, la infección cardiovascular en general, es una enfermedad médico-quirúrgica compleja que requiere un tratamiento multidisciplinario precoz, específico y agresivo. A pesar de los avances médicos, ésta sigue siendo una enfermedad con una morbi-mortalidad elevada, por lo que el tratamiento antibiótico se complementa en un 40-50% de los pacientes mediante intervención quirúrgica. Por lo tanto, es necesario conocer las opciones que pueden llegar a ser utilizadas para extirpar el tejido infectado. El objetivo de este trabajo es discutir aspectos de interés en la cirugía de la endocarditis infecciosa.

Abstract: Infective endocarditis (IE) is a complex disease that requires a multidisciplinary approach and early and aggressive treatment. Despite médical and surgical advances, this disease still has high morbidity and mortality. The antibiotic treatment is complemented in 40-50% of the cases with surgical intervention. Thus, it is useful to be aware of the possibilities that might be contemplated in order to excise the infected tissues. The aim of this work is to discuss current surgical aspects of interest in the surgery IE.

Comparación de los espaciadores articulados vs. fijos en la revisión de la infección periprotésica de rodilla / Comparison between articulating vs. fixed spacers in revision for periprosthetic knee infection

Introducción: Los espaciadores de cemento con antibiótico pueden ser fijos o articulados y se logra un resultado similar con ambos para erradicar una infección. Nuestro objetivo fue comparar el rango de movilidad articular y los resultados funcionales después del reimplante. Materiales y Métodos: Estudio de cohorte retrospectiva de pacientes sometidos a una revisión de la prótesis de rodilla por infección, en dos tiempos quirúrgicos. Se analizó la funcionalidad según el Knee Society Score (KSS) al año de la cirugía y se registró el rango de movilidad a los 45 días. Se registraron el grado de defecto óseo, dolor, satisfacción, las complicaciones y la recidiva de la infección. Resultados:Se incluyeron 103 pacientes (40 con espaciador articulado, 63 con espaciador fijo). El grupo con espaciador articulado tuvo una mediana 2,5° mayor en la movilidad final (102,5; RIC 95-110 vs. 100; RIC 90-105, p 0,01). Según el KSS funcional y el KSS de rodilla, no hubo diferencias entre ambos grupos. No hubo diferencias en el grado de satisfacción, dolor y el tiempo hasta el reimplante. Las complicaciones fueron similares en ambos grupos, con una tasa de reinfección sin diferencias estadísticamente significativas. Conclusión: Los espaciadores articulados proporcionaron un beneficio en el rango de movilidad después del reimplante de la prótesis. Nivel de Evidencia: III

Introduction: Cement spacers with antibiotics can be fixed or articulating, with similar results in eradicating infection. Our objective was to compare joint range of motion (ROM) and functional outcomes after reimplantation. Materials and Methods: A retrospective cohort study of patients who had undergone a knee prosthetic revision due to infection in two surgical stages. Functionality was analyzed according to the Knee Society Score (KSS) one year after surgery and ROM was recorded 45 days after surgery. Bone defect, pain, satisfaction, complications, and recurrence of infection were recorded. Results:A total of 103 patients were included. 40 with articulating spacers and 63 with fixed spacers. The articulating spacer group presents a median of 2.5 degrees greater in final mobility (102.5 IQR 95-110 vs 100 IQR 90-105, p 0.01). The KSS functional scale and KSS of the knee did not show differences between two groups. There were no differences concerning satisfaction, pain, and time until reimplantation. Complications were similar in both groups, with a reinfection rate without statistically significant differences. Conclusion: Articulating spacers have shown a benefit in ROM after prosthetic reimplantation. Level of Evidence: III

¿Qué factores hacen fallar un reimplante de cadera luego de una revisión en dos tiempos? / What factors cause hip reimplantation to fail after a two-stage revision hip arthroplasty?

Introducción: El objetivo del estudio fue analizar la supervivencia sin recurrencia de infección en pacientes con reemplazo total de cadera tratados con revisión en dos tiempos, valorando el impacto del cultivo intraoperatorio y la congelación positiva en el reimplante. materiales y métodos: Estudio retrospectivo de 96 casos con infección periprotésica crónica, según los criterios de la MusculoSkeletal Infection Society, sometidos a los dos tiempos quirúrgicos en nuestra institución, entre 2008 y 2013. El seguimiento promedio fue 90 meses. La falla séptica se definió sobre la base de un consenso tipo Delphi modificado. La supervivencia sin falla séptica se definió sobre la base del estimador de Kaplan-Meier. Se compararon los resultados de supervivencia en función del cultivo intraoperatorio y de los estudios de anatomía patológica por congelación mediante la prueba del orden logarítmico. Resultados: La supervivencia sin falla séptica fue del 82,65% a los 2 años (IC95% 73,25-88,99%), 80,40% a los 5 años (IC95% 70,70-87,17%) y 77,32% a 6-10 años (IC95% 66,90-84,33%). Hubo significativamente más fallas en los pacientes con un cultivo positivo en el reimplante que en aquellos con un cultivo negativo (prueba del orden logarítmico, p = 0,0208), y en quienes tuvieron un estudio anatomopatológico por congelación positivo en el reimplante que en aquellos con un resultado negativo (prueba del or-den logarítmico, p = 0,0154). Conclusiones: Los reimplantes sin recurrencias infecciosas por, al menos, 6 años tuvieron un riesgo de falla séptica muy bajo. Cuando se detectó un cultivo o una congelación positivos, la falla séptica fue significativamente mayor. Nivel de Evidencia: IV

Background: We analyzed the survivorship free-from-septic failure in a series of THA cases treated with a two-stage protocol at long-term follow-up, with a special focus on the relevance of positive frozen section and positive intraoperative culture taken during the reimplantation. Materials and methods: We retrospectively reviewed data from 96 cases who met the Musculoskeletal Infec-tion Society criteria for periprosthetic joint infection and who had undergone both stages of a two-stage protocol at our institution between 2008-2013. Mean follow-up was 90 months. Treatment failure was determined with a modified Delphi-based consensus definition. Kaplan-Meier estimate was used to determine survivorship free-from-septic failure. Log-Rank test was used to compare variables associated with septic failure. Results: Survival free-from-septic failure was 82.65% at 2 years (95%CI 73.25%-88.99%), 80.40% at 5 years (95%CI 70.70%-87.17%) and 77.32% at 6-10 years (95%CI 66.90%-84.33%). Patients with a positive culture at reimplantation had significantly more septic failures than those without it (Log-Rank test, p=0.0208), while patients with a positive frozen section at reimplantation had significantly more septic failures than those without it (Log-Rank test, p=0.0154). Conclusions: Reimplantations that remained at least 6 years without septic recurrences had a very low risk of further septic failure. Both positive frozen section and intraoperative culture at reimplantation were risk factors for septic failure. Level of Evidence: IV

Colgajo neurocutáneo safeno y recambio de espaciador de cemento en el manejo de una artroplastia de rodilla infectada con defecto de cobertura cutánea. Reporte de un caso / Saphenous neurocutaneous flap and cement spacer replacement in the management of arthroplasty of an infected knee with a soft tissue coverage defect. Case report

Los defectos de cobertura asociados a una infección de la prótesis son un desafío al cual nos enfrentamos los cirujanos ortopédicos en el posoperatorio de un reemplazo articular. El objetivo de este artículo es comunicar un caso de defecto de cobertura tratado con un colgajo neurocutáneo safeno por una artroplastia de rodilla infectada. Se recambió el espaciador y se cubrió el defecto tegumentario con colgajo neurocutáneo safeno en un mismo tiempo. Conclusiones:El colgajo neurocutáneo safeno proporciona una adecuada cobertura en la cara anterior de la rodilla y permite tratar defectos tegumentarios asociados a una infección de la prótesis. Nivel de Evidencia: IV

Soft tissue defects in the setting of periprosthetic joint infection represent serious problems for orthopaedic surgeons following total joint replacement. This report aims is to show our experience using the proximal-based saphenous neurocutaneous flap for the reconstruction of a wound defect in the treatment of a periprosthetic knee infection. A new cement spacer was placed and a neurocutaneous saphenous flap was performed in the same stage. Conclusions: Soft tissue defects around the knee can be effectively solved with the neurocutaneous saphenous flap, which provides an adequate coverage to this joint within the context of infected arthroplasty. Level of Evidence: IV

Guidelines for the diagnosis and treatment of prosthetic joint infection / 中华外科杂志

Prosthetic joint infection is one of the most serious complications after artificial joint replacement.Accurate diagnosis and proper standardized treatment are the keys to improve the cure rate of prosthetic joint infection,reduce the rate of recurrence and disability,and restore limb function.Regarding the diagnosis and treatment of prosthetic joint infection,although relevant research has progressed rapidly in recent years,there are still many problems that have not been well understood and explained,and there are still big differences and controversies in many aspects.This has brought a lot of confusion to clinicians during their daily practice.In order to make the diagnosis and treatment of prosthetic joint infection in China more standardized,a group of domestic experts in related fields was organized by the Joint Surgery Committee of the Chinese Orthopaedic Association to search the literature and integrate expert opinions,and compiled the "Guidelines for the diagnosis and treatment of prosthetic joint infection".Those most important and clinically concerned issues are elaborated,including the diagnostic criteria, standardized diagnostic algorithm,proper application of important tests,treatment principles,and the correct selection of various treatment options.Targeted and actionable recommendations are proposed.This guideline is expected to provide references for domestic colleagues in the diagnosis and treatment of prosthetic joint infection.