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

Incidence of surgical site infection after craniotomy: comparison between three months and twelve months of epidemiological surveillance

ABSTRACT Objective: To determine the incidence of surgical site infection in patients undergoing craniotomy and to compare 12-month and 3-month post-discharge surveillance periods in terms of their impact on the incidence of surgical site infection in those patients. Methods: This was a retrospective cohort study involving 173 adult patients submitted to "clean" craniotomy, with or without implants, during the six-month period, at a university hospital in the city of São Paulo, Brazil. All the patients were evaluated in the pre-, trans- and postoperative periods and were followed for 12 months to analyze the development of surgical site infections. Results: Of the 173 patients undergoing craniotomy during the study period, 20 developed an surgical site infection during the first, and 12 months after discharge, the overall incidence of surgical site infection therefore being 11.56%, compared with a 1-month incidence of 8.67% and a 3-month incidence of 10.98%. Among the 106 patients who received implants, the 1-, 3-, and 12-month incidence of surgical site infection was 7.54% (n= 8), 8.49% (n= 9), and 9.43% (n= 10), respectively. Among the 67 patients who did not receive implants, the 1-, 3-, and 12-month incidence of surgical site infection was 10.44% (n= 7), 14.92% (n= 10), and 14.92% (n= 10), respectively. Conclusion: The incidence of surgical site infection after craniotomy is high. Reducing the duration of the post-discharge surveillance period from 12 months to 3 months did not cause significant losses in the numbers of surgical site infection identified or a substantial decrease in their incidence.

Prevalence and antibiogram of methicillin resistant Staphylococcus aureus isolated from medical device-related infections; a retrospective study in Lahore, Pakistan

Abstract INTRODUCTION: With the advancement of medicine and surgery, various types of medical devices have become part of treatment strategies. METHODS: Identification and antimicrobial sensitivity testing were done according to CLSI guidelines following standard microbiological practices. RESULTS: Urinary catheter infections (31%) were most frequent followed by central venous catheter (18%) and orthopedic implants (15%). Methicillin resistant Staphylococcus aureus (MRSA) was a major cause of device-related infection after Escherichia coli (21%); other pathogens were Klebsiella pneumoniae (14%), Pseudomonas spp. (10%), Acinetobacter spp. (8%) and Candida species (7%). None of MRSA was resistant to vancomycin (MIC ≥16µg/mL). Resistance rates were 98% and 97% for ofloxacin and ciprofloxacin, respectively. CONCLUSIONS Escherichia coli and MRSA are major pathogens of medical device-related infections.

Infecciones osteoarticulares en pacientes del Hospital del Instituto de Seguridad del Trabajador (IST) de Viña del Mar: periodo 2012-2013 / Osteoarticular infections in patients of the Hospital del Instituto de Seguridad del Trabajador in Viña del Mar (Chile): period 2012-2013

INTRODUCCIÓN: Las infecciones osteoarticulares son un desafío frecuente en la práctica traumatológica diaria. En Chile y en los distintos hospitales de la región de Valparaíso son escasos los trabajos con relación al tema, lo que es fundamental para optimizar el tratamiento, tanto quirúrgico como médico, de estas infecciones. OBJETIVOS: Describir las infecciones osteoarticulares del Hospital del IST de Viña del Mar durante el periodo 2012-2013. MATERIALES Y MÉTODO: Trabajo descriptivo retrospectivo de una serie de casos. Se revisaron las fichas clínicas de los pacientes que cursaron con alguna infección osteoarticular y se obtuvieron los datos demográficos y clínicos de cada paciente. RESULTADOS: Treinta pacientes fueron incluidos. Dieciséis (53,3%) fueron hombres con un promedio de edad de 38,5años. El 50% correspondieron a infecciones asociadas a la atención de salud. Las principales infecciones fueron asociadas a material de osteosíntesis. El agente más frecuente fue el Staphylococcus aureus meticilinosensible (SAMS). En la mayoría de los casos se realizó aseo quirúrgico, toma de cultivos e inicio de antibióticos con ceftriaxona más clindamicina. CONCLUSIONES: Las infecciones osteoarticulares ocurrieron principalmente en hombres jóvenes, fueron infecciones asociadas a material de osteosíntesis y producidas por SAMS.

INTRODUCTION: Osteoarticular infections are a common challenge in everyday trauma practice. In Chile, and in different hospitals in the region of Valparaiso, there are few studies on the issue, which is essential to optimise both surgical and medical treatment of these infections. OBJECTIVES: To describe the osteoarticular infections in the Hospital del Instituto de Seguridad del Trabajador (IST) of Viña del Mar during the 2012-2013 period. MATERIALS AND METHODS: A retrospective descriptive study was performed on a series of cases. A review was made of the medical records of patients with any osteoarticular infection. Demographic and clinical data were obtained from each patient. RESULTS: Of the total of 30 patients included, 16 (53.3%) were male with a mean age of 38.5 years. Half (50%) of the infections were associated with health care. Major infections were associated with osteosynthesis material. The most frequent agent was Methicillin Susceptible Staphylococcus aureus (MSSA). In most cases surgical cleanliness, taking of microbiological cultures, and antibiotic treatment with ceftriaxone plus clindamycin, was performed. CONCLUSIONS: Osteoarticular infections occurred mainly in young men, were infections associated to osteosynthesis material, and caused by MSSA.

Factores de riesgo e infección del sitio quirúrgico en procedimientos de cirugía ortopédica con prótesis / Risk factors related to surgical site infection in orthopedic prosthesis surgery

Objective: to identify the risk factors for surgical site infections (SSI) in patients with surgical management fractures with internal fixation or prosthetic material. Materials and Methods: a cross-sectional study was conducted in a tertiary institution in Armenia-Colombia in 2008 and 2009 in 223 patients. Results: The superficial incisional infection frequency was 9,4% (n: 21), and deep incisional infection was 7,6% (n: 17); there were no organ/space SSI.; the highest rates of infection were observed in patella fractures (50%), acromio-clavicular joint (25%), and femur (23,7%). The infections were caused by: S. aureus, Enterobactergergoviae y Enterobacteraerogenes. There was an association with clean-contaminated wounds compared to clean wounds (OR 2,2), comminuted fractures (OR 2,1) multiple fractures (OR 2,9) and patella surgery (OR 3,1). Conclusions: the severity of the fracture and the degree of contamination were predisposing factors to infection.

Objetivo: Identificar factores de riesgo para infecciones del sitio quirúrgico en pacientes con fracturas quirúrgicas de manejo con material de osteosíntesis o prótesis. Material y Método: Se realizó un estudio de corte transversal en una institución de tercer nivel de Armenia- Colombia en 2008 y 2009 en 223 pacientes. Resultados: La frecuencia de infección incisional superficial fue de 9,4% (n: 21), y de incisional profunda 7,6% (n: 17); no hubo infecciones de órgano/espacio; las mayores frecuencias de infección se observaron en fracturas de rótula (50%), articulación acromio- clavicular (25%) y fémur (23,7%). La etiología infecciosa fue por: Staphylococcus aureus, Enterobacter gergoviae y Enterobacter aerogenes. Se encontró asociación con heridas limpia-contaminadas comparadas con heridas limpias (OR 2,2), fracturas conminutas (OR 2,1), fracturas múltiples (OR 2,9), y cirugía de rótula (OR 3,1). Conclusiones: La gravedad de la fractura y el grado de contaminación se evidenciaron como predisponentes para infección.

Incidência de infecções em artroplastias de quadril e joelho em pacientes com artrite reumatoide e osteoartrite / Incidence of infectious complications in hip and knee arthroplasties in rheumatoid arthritis and osteoarthritis patients

INTRODUÇÃO: A artrite reumatoide (AR) é uma das principais indicações de artroplastia total do quadril (ATQ) ou joelho (ATJ). Estudos internacionais indicam a AR como fator de risco para infecções de prótese. OBJETIVOS: Comparação entre pacientes com AR e osteoartrite (OA) de outras etiologias em relação à incidência de infecções de prótese, infecções incisionais e outras infecções sistêmicas pós-operatórias em ATQ e ATJ. MÉTODOS: Coorte retrospectiva, comparativa, de pacientes acompanhados após a realização de ATQ ou ATJ no Hospital SARAH-Brasília, no período entre 1996 e 2007. RESULTADOS: Setenta e cinco artroplastias em pacientes com AR foram identificadas, das quais 28 ATJ e 47 ATQ. Como controles, foram selecionadas 131 cirurgias em pacientes com OA, das quais 56 ATJ e 75 ATQ, de maneira aleatória e estratificada pela cirurgia e pelo gênero. Não houve diferenças significativas entre os grupos de AR e OA no que diz respeito às taxas de infecções de prótese (respectivamente, ATJ 7,1% vs. 0% e ATQ 2,1% vs. 0%, ambos com P > 0,1), infecção incisional (ATJ 14,3 vs. 3,3% e ATQ 4,3 vs. 1,3%, ambos com P > 0,1) e infecção sistêmica (ATJ 7,1 vs. 3,6%, P = 0,92 e ATQ 4,3 vs. 10,7%, P > 0,1). Após regressão logística múltipla, não houve alteração dos resultados. CONCLUSÕES: A presença de AR não foi identificada como fator de risco para infecções perioperatórias em ATQ e ATJ em casuística do Hospital SARAH-Brasília, em comparação com o grupo de pacientes com OA primária ou secundária a doenças não inflamatórias. A baixa incidência de infecções em ambos os grupos pode explicar os nossos achados.

INTRODUCTION: Rheumatoid arthritis (RA) is one of the major indications of total hip (THA) or knee (TKA) arthroplasty. International studies have suggested that RA is a risk factor for prosthesis infections. OBJECTIVES: To compare patients with RA and patients with osteoarthritis (OA) of other etiologies with regard to the incidence of prosthesis, incisional, and other systemic postoperative infections in THA and TKA. METHODS: Retrospective, comparative cohort of patients followed up after undergoing THA or TKA at the Hospital SARAH-Brasília, from 1996 to 2007. RESULTS: Seventy-five arthroplasties (28 TKA and 47 THA) were identified in RA patients. As controls, 131 surgeries (56 TKA and 75 THA) in OA patients were randomly selected and stratified by surgery and gender. No significant difference was observed between the RA and OA groups regarding the rates of prosthesis infections (TKA 7.1% vs. 0% and THA 2.1% vs. 0%, respectively, both with P > 0.1), incisional infections (TKA 14.3% vs. 3.3% and THA 4.3 vs. 1.3%, respectively, both with P > 0.1), and systemic infections (TKA 7.1% vs. 3.6%, P = 0.92 and THA 4.3% vs. 10.7%, P > 0.1, respectively). After multiple logistic regression, the results did not change. CONCLUSIONS: RA was not identified as a risk factor for perioperative infections in THA and TKA in this case series of the Hospital SARAH-Brasília, as compared with the group of patients with primary OA or OA secondary to non-inflammatory diseases. The low incidence of infections in both groups may explain our findings.

Actualización sobre endocarditis infecciosa en válvula protésica / Up-date in prosthetic valve endocarditis

La endocarditis en válvulas protésicas es aún tema de controversia, en especial en referencia al tipo de tratamiento que se debe elegir. Debido a que los conocimientos actuales sobre esta patología están basados principalmente en la literatura y por ende, en sus variados exponentes (experiencias clínicas, revisiones sistemáticas, guía clínicas de diferentes sociedades de cardiología, estudios observacionales, entre otros), es necesario hacer una actualización continua de la información. Esta revisión bibliográfica se centra en la incidencia, etiología, diagnóstico y tratamiento de la endocarditis protésica. En ella se llega la conclusión de que los principales microorganismos productores de esta patología son el Estafilococo aureus y el Estafilococo coagulasa-negativo. También se reconocen aquellos factores de riesgo para los cuales la cirugía es mandatoria, entre los que destacan las infecciones por S. aureus y la endocarditis protésica complicada, ya sea por insuficiencia cardíaca, alteración de la conducción, formación de abscesos y/o embolias recurrentes. De esta manera, con la información recopilada, se identificaron aquellos pacientes con opción a tratamiento médico, y aquellos con indicación de manejo quirúrgico. Para presentar mejor nuestras conclusiones, se construyeron esquemas de fácil consulta y lectura, para apoyar la decisión del tipo de manejo frente a una endocarditis en válvulas protésicas.

Prosthetic valve endocarditis is still a matter of controversy especially the type of treatment that should be chosen for an individual patient. Since the current knowledge of this pathology is based mainly on the literature and in its many and varied exponents (clinical experience, systematic review, practice guidelines of cardiology associations, observational studies, etc), it is necessary to update the information continuously This review is focused mainly in the incidence, etiology diagnostics and treatment of prosthetic endocarditis. The principal microroganisms related to this pathology are Staphylococcus aureus and coagulase-negative Staphyloccoco. Risk factors were identified for witch surgery is mandatory, such us Staphylococcus aureus infection and a complicated prosthetic valve endocarditis (cardiac failure, conduction abnormalities, abscess formation and recurrent embolism). With this information, patients that could have a medical treatment option can be recognized, as well as those who will require surgery. In order to present in a better way our conclusions, easily reading diagrams were included to facilitate the decision process when facing up a prosthetic valve endocarditis.

Estudio retrospectivo de la endocarditis infecciosa en diferentes grupos de riesgo / Infective endocarditis in an internal medicine ward

Background: Due to the increasing number of intravenous drug users, subjects with immune deficiencies or with prosthetic valves, infective endocarditis (IE) continues to be prevalent and to have a high mortality. Aim: To review all cases of infective endocarditis diagnosed in an Internal Medicine Service. Material and methods: Retrospective review of medical records of all patients with infective endocarditis, hospitalized in an Internal Medicine ward, between 1989 and 2003. Dukes criteria were used to define definitive, possible and less probable cases of IE. Results: Eighty seven patients with definite IE were identified (66 males, age range 19-84 years), with a mean incidence of 5.3 per 1000 hospitalizations. IE in intravenous drugs users was usually caused by Staphylococcus aureus and presented high risk of embolism (RR: 3,21). Subjects aged over 70 years had a relative risk of mortality of 5.5. Hospital acquired IE was associated with advanced age and IV catheters appeared as the only predisposing factor. Patients with prosthetic valves were also older, their main complication was abscess formation and their mortality was higher. Conclusions: A closer approach to differential conditions of patients, according to age, intravenous drug use or the presence of prosthetic valves, is necessary

Routine prophylactic antibiotics for arthroplasty patients receiving dental care. Is it necessary?

Much of the debate regarding the prophylactic use of antibiotics for patients who have had a total joint replacement has focussed on their use before dental procedures. Despite the fact that almost all orthopaedic surgeons routinely recommend antibiotics for patients with prosthetic joints who require dental treatment, there is little evidence of a definitive link between transient bacteraemia occurring during dental procedures and late infections around prosthetic joints. An extensive review of the literature reveals that most authors recommend prophylactic antibiotics in high-risk patients or in those who undergo extensive dental surgery

Infecciones en cirugía de artroplastía de cadera: resultados del sistema de vigilancia epidemiológica de las infecciones intrahospitalarias: 1996-1999 / Infections in hip arthroplasty: results of the nosocomial infections surveillance system, Chile 1996-1999

La vigilancia epidemiológica de las infecciones en cirugía de prótesis se estableció en los hospitales chilenos a partir de 1996. Entre 1996 y 1999 se notificaron 134 infecciones de 3,5 porciento. La vigilancia epidemiológica en Chile no diferencia infecciones de la herida operatoria de las de implantes propiamente tal y el período de observación y/o post hospitalización más inmediato. En esta casuística hubo predominio de bacilos gram negativos no fermentadores (33,3 porciento) principalmente acinetobacter baumannii. Las cocáceas gram positivas representaron el 23,8 porciento de los agentes etiológicos. Se observó que a mayor volumen de operaciones menor es la tasa de intervenciones quirúrgicas y 2,9 porciento en hospitales de alto volumen quirúrgico). Los hallazgos observados sugieren factores de riesgo que deben ser estudiados, como el tiepo de hospitalización preoperatorio y el grado de experiencia de los centros quirúrgicos

Infecciones en prótesis articular / Prosthetic joint infections

Se realizó un estudio retrospectivo con el objetivo de conocer las principales características clínicas y epidemiológicas de las infecciones en prótesis articulares de cadera y rodilla. Para Ello se analizaron los registros disponibles desde 1993 identificando 19 episodios en 18 pacientes. La tasa de infección global fue de 2,84 porciento en 633 implantes y la de infecciones intrahospitalarias de 1,11 porciento. Un 70 porciento de los casos se presentó antes de los 18 meses de la instalación. La edad promedio de los pacientes fue de 70,5 años y 83 porciento era de sexo femenino. Tres pacientes tenían antecedentes de artritis reumatoidea y utilizaban corticosteroides. Los cultivos fueron positivos en 18 de los 19 episodios, predominando el género staphylococcus (49 porciento) y los bacilos gram negativos (37 porciento). En 12 de los 19 episodios se retiró la prótesis infectada (63 porciento). La sobrevida libre de recurrencias fue sifnificativamente superior en aquellos pacientes tratados quirúrgicamente durante el primer mes de hospitalización