Interval between two-stage exchanges: what is optimal and how do you know?

BACKGROUND: Two-stage exchange arthroplasty remains the most popular option for the treatment of chronic periprosthetic joint infection (PJI). Determining infection eradication and optimal timing of reimplantation can be challenging. Information to allow for a truly informed evidence-based decision is scarce. METHODS: We conducted a critical review of available evidence on the presently available tests to help determine timing of reimplantation. RESULTS: Serology is traditionally used to follow up patients after the first stage. Despite tradition mandates waiting for normal inflammatory markers, there is actually no evidence that they correlate with persistent infection. The role of synovial fluid investigation between stages is also explored. Cultures lack sensitivity and neither differential leukocyte counts nor alternative biomarkers have proven to be accurate in identifying persistent infection with a spacer in situ. We also examined the evidence regarding the optimal time interval between resection and reimplantation and whether there is evidence to support the implementation of a two week "antibiotic holiday" prior to proceeding with reimplantation. Finally, wound healing and other important factors in this setting will be discussed. CONCLUSION: Currently there are no accurate metrics to aid in the decision on the optimal timing for reimplantation. Decision must therefore rely on the resolution of clinical signs and down trending serological and synovial markers.

Simple and inexpensive synovial fluid biomarkers for the diagnosis of prosthetic joint infection according to the new EBJIS definition.

Introduction: diagnosis of periprosthetic joint infection (PJI) is challenging, as no single test has absolute accuracy. The purpose of this study was to assess the utility of different simple synovial biomarkers in the diagnosis of PJI as defined by the European Bone and Joint Infection Society (EBJIS). Methods: we retrospectively identified all patients undergoing revision hip or knee arthroplasty from 2013 to 2019 on our prospectively maintained database. Only patients with minimum required infection diagnostic workup were included in the study. Patients with comorbidities that may influence the accuracy of synovial biomarkers were excluded. Receiver operator characteristic (ROC) curves were utilised to assess the diagnostic utility of synovial fluid white blood cell (WBC) count, polymorphonuclear leukocyte percentage (PMN %), C-reactive protein (CRP), adenosine deaminase (ADA), and alpha-2-microglobulin (A2M). Results: in total, 102 patients met the inclusion criteria. Of these, 58 were classified as infection unlikely, 8 as infection likely, and 36 as infection confirmed. Synovial WBC count (area under the curve (AUC) 0.94) demonstrated the best utility for the diagnosis of PJI, followed by PMN % (AUC 0.91), synovial CRP (AUC 0.90), ADA (AUC 0.82), and A2M (AUC 0.76). We found added value in the combined interpretation of different biomarkers. We calculated high sensitivity and negative predictive value if at least two of them are negative and high specificity and positive predictive value if at least two are elevated. Conclusion: current results show that synovial fluid investigation is a useful tool for the diagnosis of PJI, and the combined interpretation of simple and inexpensive biomarkers demonstrated improved diagnostic accuracy.

Guideline for management of septic arthritis in native joints (SANJO).

This clinical guideline is intended for use by orthopedic surgeons and physicians who care for patients with possible or documented septic arthritis of a native joint (SANJO). It includes evidence and opinion-based recommendations for the diagnosis and management of patients with SANJO.

Multidisciplinary Approach to Multiple Multiresistant Agent Infection of Instrumented Spine Surgery: A Case Report.

CASE: We report the case of a patient with consecutive infections with several multidrug-resistant agents-including carbapenem-resistant strains of Klebsiella pneumoniae among others-from a surgical wound infection after lumbar spine fusion, only successfully treated after the resort to novel antibiotics (ceftazidime-avibactam) in combination therapy. CONCLUSIONS: Multidrug resistance has become a major challenge in today's medicine. Care should be taken to avoid their emergence, but when present, a multidisciplinary approach is mandatory to ensure clinically up-to-date treatment choices. Multimodal antibiotic schemes tend to show the most promising results, with which successful infection resolution can still be achieved.

Adult Native Joint Septic Arthritis: A Nine-Year Retrospective Analysis in a Portuguese University Hospital.

INTRODUCTION: Septic arthritis of a native joint represents a medical emergency. Drainage and effective antibiotic treatment are critical to avoid joint destruction and long-term impairment. The aim of this study was to evaluate epidemiological and clinical characteristics of patients with the diagnosis of septic arthritis to help establish local guidelines for empirical antibiotic treatment. MATERIAL AND METHODS: Retrospective analysis of adult patients admitted at Centro Hospitalar Universitário do Porto from 2009 to 2017 with suspected native joint septic arthritis. Relevant demographics, microbiology findings and respective antibiotic susceptibilities were analysed. RESULTS: Ninety-seven patients, predominantly males (59.8%) with a median age of 61 years old were included. The most commonly reported comorbidity associated with septic arthritis was diabetes mellitus (20.6%). The knee was the most commonly affected joint (71.1%). Arthrocentesis was performed in all patients, but only 50.5% had positive microbial growth in the synovial fluid. Staphylococcus aureus was the most frequently identified microorganism, 86% of which were methicillin susceptible. Gram-negative bacteria were the causative agent in 15% of cases. A wide range of empirical antibiotic regimens were prescribed with a combination of vancomycin/carbapenem being the most common (30.9%). Analysis of antibiotic susceptibility profiles revealed that amoxicillin/clavulanate would have been appropriate as the initial regimen in 89% of cases. DISCUSSION: The main causative pathogen was Staphylococcus aureus, with methicillin resistant Staphylococcus aureus remaining rare. The proportion of Gram-negative bacteria implies that these agents should be covered by empirical treatment, although no case of Pseudomonas infection has been identified. Therefore, antipseudomonal coverage is not necessary in empirical regimens. CONCLUSION: Routine coverage of methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa is not warranted but must be considered when specific risk factors are found. Amoxicillin/clavulanate can provide adequate antibiotic coverage as an empirical treatment for adult native joint septic arthritis. Its use may allow a reduction in use of broader spectrum antibiotics.

Introdução: A artrite séptica representa uma patologia grave que pode levar à destruição articular e diminuição funcional a longo prazo. Adicionalmente à drenagem articular, uma antibioterapia efetiva é crucial. O objetivo deste estudo consistiu em avaliar as características epidemiológicas e clínicas dos doentes admitidos com diagnóstico de artrite séptica e analisar a terapêutica antimicrobiana, estabelecendo orientações locais de tratamento antibiótico empírico. Material e Métodos: Análise retrospetiva de doentes adultos admitidos no Centro Hospitalar Universitário do Porto com artrite séptica de articulação nativa de 2009 a 2017. Foram revistos os resultados microbiológicos, os perfis de suscetibilidade aos antimicrobianos e os registos médicos. Resultados: Dos 97 doentes incluídos, 59,8% eram do género masculino, com uma idade média de 61 anos. A comorbilidade mais comum foi a diabetes mellitus (20,6%). O joelho foi a articulação mais afetada (71,1%). Realizou-se artrocentese em todos os doentes, com isolamento microbiano em 50,5% dos produtos. O Staphylococcus aureus foi o microrganismo mais frequente, sendo sensível à meticilina, em 86% dos casos. As bactérias Gram-negativo foram o agente causal em 15% das infeções. A associação do carbapenemo e vancomicina foi a antibioterapia empírica mais comummente iniciada (30,9%), embora em 89% dos casos a amoxicilina/clavulanato teria sido apropriada como regime inicial. Discussão: O principal agente etiológico foi o Staphylococcus aureus, continuando o Staphylococcus aureus resistente à meticilina a ser um agente raro. A percentagem de bactérias Gram-negativo implica a sua cobertura como terapêutica empírica, embora não tenha havido casos de infeção por Pseudomonas. Por isso, a utilização empírica de um antibiótico com atividade antipseudomónica não é necessária. Conclusão: A cobertura antibiótica de Staphylococcus aureus resistente à meticilina e Pseudomonas não é obrigatória, mas pode ser considerada na presença de alguns fatores de risco específicos. A amoxicilina/ clavulanato é uma antibioterapia empírica adequada para a artrite séptica de articulação nativa, permitindo reduzir a utilização inadequada de antibióticos de espectro mais alargado.

SARS-CoV-2 Infection Drives a Glycan Switch of Peripheral T Cells at Diagnosis.

COVID-19 is a highly selective disease in which SARS-CoV-2 infection can result in different clinical manifestations ranging from asymptomatic/mild to severe disease that requires hospitalization. In this study, we demonstrated that SARS-CoV-2 infection results in a glycosylation reprogramming of circulating lymphocytes at diagnosis. We identified a specific glycosignature of T cells, defined upon SARS-CoV-2 infection and apparently triggered by a serological factor. This specific glycan switch of T cells is detected at diagnosis being more pronounced in asymptomatic patients. We further demonstrated that asymptomatic patients display an increased expression of a viral-sensing receptor through the upregulation of DC-SIGN in monocytes. We showed that higher levels of DC-SIGN in monocytes at diagnosis correlates with better COVID-19 prognosis. This new evidence pave the way to the identification of a novel glycan-based response in T cells that may confer protection against SARS-CoV-2 infection in asymptomatic patients, highlighting a novel prognostic biomarker and potential therapeutic target.

Optimal microbiological sampling for the diagnosis of osteoarticular infection.

Infection is a dire complication afflicting every field of orthopaedics and traumatology. If specific clinical, laboratory and imaging parameters are present, infection is often assumed even in the absence of microbiological confirmation. However, apart from confirming infection, knowing the exact infecting pathogen(s) and their antimicrobial susceptibility patterns is paramount to help guide treatment. Every effort should therefore be undertaken with that goal in mind.Not all microbiological findings carry the same relevance, and knowing exactly how and where a sample was collected is key. Several different sampling techniques are available, and one must be aware of both advantages and limitations. Microbiological sampling alternatives in some of the most common clinical scenarios such as native and prosthetic joint infections, osteomyelitis and fracture-related infections, spinal and diabetic foot infections will be discussed.Orthopaedic surgeons should also be aware of basic laboratory sample processing techniques as they have a direct impact on the way specimens should be dealt with and transported to the laboratory. Only by knowing these basic principles will surgeons be able to participate in the multidisciplinary discussion and decision making around how to interpret microbiological findings in each specific patient. Cite this article: EFORT Open Rev 2021;6:390-398. DOI: 10.1302/2058-5241.6.210011.

Leprosy presenting as remitting seronegative symmetrical synovitis with pitting oedema syndrome - a case report.

BACKGROUND: Leprosy typically manifests with skin and peripheral nerve involvement. Musculoskeletal complaints are the third most common, and can be the sole presenting manifestation. They range from arthralgia/arthritis in reactional states to full mimics of systemic rheumatic diseases. Remitting Seronegative Symmetrical Synovitis with Pitting Oedema syndrome has only been described once in a patient with already diagnosed Leprosy. CASE REPORT: A 68-year-old male, from an endemic region of familial amyloid polyneuropathy, presented with an inaugural Remitting Seronegative Symmetrical Synovitis with Pitting Oedema like syndrome, more that 20 years after travelling to Leprosy endemic areas. Arthritis would resurface whenever oral prednisone was tapered, so methotrexate was started, controlling the complaints. Only one year later, after the appearance of peripheral neuropathy and skin lesions, it was possible to diagnose Leprosy, through the identification of Mycobacterium leprae bacilli in a peripheral nerve biopsy. CONCLUSION: This report is an example of the heterogeneity of manifestations of Leprosy, namely rheumatic, and the challenge of diagnosing it when typical complaints are absent. It is also a reminder that this disease should be considered whenever a patient with a combination of skin/neurologic/rheumatic complaints has travelled to endemic countries in the past.

[Human Psittacosis: A Case Report]. / Psitacose: A Propósito de Um Caso Clínico.

Psittacosis is a rare disease caused by Chlamydophila psittaci, an intracellular bacteria transmitted by contaminated birds. The clinical and radiological presentations are nonspecific. We describe a case of a 42-year-old woman, with known exposure to birds, who presented to the emergency department with one-week evolution of myalgia, polyarthritis, and respiratory symptoms. At admission, she had fever, respiratory failure, raised inflammatory markers and bilateral interstitial infiltrates at chest radiography. Considering the clinical findings and epidemiological background, we raised the hypothesis of a Chlamydophila psittaci atypical pneumonia that was serologically confirmed. Tetracyclines are the mainstay of treatment and the macrolides are an effective alternative. We highlight the importance of the epidemiological context in the early diagnosis and treatment of this infection.

A psitacose é uma entidade rara provocada pela Chlamydophila psittaci, uma bactéria intracelular obrigatória que se transmite através do contacto com aves contaminadas. A apresentação clínica e imagiológica é inespecífica. Reporta-se o caso clínico de uma mulher de 42 anos, com história de exposição a pássaros, que se apresenta no Serviço de Urgência com um quadro de mialgias, poliartralgias e clínica de infeção respiratória, com uma semana de evolução. À admissão, encontrava-se febril, com insuficiência respiratória do tipo 1, elevação dos parâmetros inflamatórios e infiltrados intersticiais difusos bilaterais na radiografia de tórax. Considerando o quadro clínico e o contexto epidemiológico de risco, colocou-se a hipótese de pneumonia atípica por Chlamydophila psittaci, confirmada serologicamente. As tetraciclinas são o esteio do tratamento, sendo os macrólidos uma alternativa eficaz. Realça-se a importância do contexto epidemiológico, para uma abordagem diagnóstica e terapêutica apropriadas.

[Late Neuroborreliosis in an Erasmus Programme Student]. / Neuroborreliose Tardia num Estudante em Programa Erasmus.

Lyme disease is an endemic zoonosis, the most prevalent tick-transmitted infection in temperate areas of Europe, North America and Asia. It is a multisystemic disease with cutaneous, musculoskeletal, neurologic and cardiac manifestations, according to the stage of the disease. We describe a case of late neuroborreliosis in an Erasmus programme student living in Porto. We discuss the importance of the epidemiological suspicion, the clinical approach, the diagnostic criteria and the most adequate treatment.

A doença de Lyme é uma zoonose endémica nos Estados Unidos da América (EUA), na Ásia e no continente europeu, nomeadamente nos países do centro da Europa. Trata-se de uma doença multissistémica, com manifestações cutâneas, articulares, neurológicas e cardíacas, que variam de acordo com a fase da doença. Apresentamos o caso de uma neuroborreliose tardia num jovem estudante belga a residir temporariamente no Porto. Discutimos a importância da suspeita epidemiológica, a investigação etiológica, os critérios de diagnóstico e o tratamento mais adequado.

Treatment of Prosthetic Joint Infection with Debridement, Antibiotics and Irrigation with Implant Retention - a Narrative Review.

Prosthetic joint infection usually requires combined medical and surgical therapy. While revision surgery is widely considered to be the gold standard surgical procedure, debridement, antibiotics and irrigation with implant retention is a very appealing alternative. There is however great controversy regarding its real worth with success rates ranging from 0% to over 90%. A number of different patient and host related variables as well as specific aspects of surgical and medical management have been described as relevant for the final outcome. Along this paper, the authors will provide the readers with a critical narrative review of the currently available literature while trying to provide concise and practical treatment recommendations regarding adequate patient selection criteria, proper surgical technique and optimal antibiotic therapy.

[Meticilin resistant Staphylococcus aureus and liver abscess: a retrospective analysis of 117 patients]. / Staphylococcus aureus resistente à meticilina e abcesso hepático: análise retrospectiva de 117 casos.

INTRODUCTION: Liver abscesses are a clinical entity difficult to diagnose and treat; therefore, a high index of suspicion is usually important. The majority of pyogenic liver abscesses are polymicrobial, with enteric and anaerobic bacteria being the most common. Staphylococcus aureus are found in around 7% of the liver abscesses, as reviewed in literature. This infection usually results from hematogenous dissemination of bacteria that's infecting some other organ. There are no published series on this matter, only case-reports. OBJECTIVES AND METHODS: In order to investigate the physiopathology, diagnosis and natural history of liver abscesses, namely those caused by methicillin-resistant Staphylococcus aureus (MRSA), we conducted a retrospective review by studying the clinical files of the patients diagnosed with liver abscess/portal pyemia between January of 2004 and December of 2009, with a total of 117 patients. RESULTS: Fever and abdominal pain were the most common symptoms. Nearly all patients had a CT scan for diagnosis. Only 81.2% of patients had microbiological products collected. The most common pathogen isolated was Escherichia coli. MRSA was isolated in 7.6% of abscesses. Percutaneous drainage combined with antibiotic therapy was the most frequent treatment used. All MRSA isolated were susceptible to trimethoprim-sulfamethoxazole and vancomycin. The underlying conditions most frequently found were biliary diseases, followed by recent abdominal surgery, which in turn was the most frequent predisponent condition in MRSA liver abscesses. The total mortality rate was 17.9%. One patient died in the group of abscesses caused by MRSA. CONCLUSION: MRSA is an important pathogen in hospital-acquired infections and intraabdominal infections are no exception. We find the association with post abdominal surgery very important. These findings have remarkable implications in therapeutics, prognosis and investigation.

Investigating a case of recurrent pleural effusion.

We describe the case of a patient with long-standing Parkinson's disease and recurrent bilateral pleural effusions. The pleural fluid was an exudate, rich in normal lymphocytes, and the echocardiogram, chest computerized axial tomography, and immunological, microbiological and cytological studies were negative. The patient had been taking bromocriptine, which can be related to chronic pleural effusions. Using Pubmed, we found about 40 cases of pleuropulmonary changes or constrictive pericarditis that were related to bromocriptine. We decided to suspend this drug, with resolution of the pleural effusion and respiratory complaints for more than a year now. We discuss possible underlining mechanisms for this and emphasize the importance of collecting the past medical history and medication and of considering possible iatrogenic effects.