We have measured the humoral response to messenger RNA (mRNA) vaccines in COVID‐19 naïve and convalescent individuals. Third doses of mRNA COVID‐19 vaccines induced a significant increase in potency ...and breadth of neutralization against SARS‐CoV‐2 variants of concern (VoC) including Omicron subvariants BA.1, BA.2, and BA.2.12.1, that were cross‐neutralized at comparable levels and less for BA.4/5. This booster effect was especially important in naïve individuals that only after the third dose achieved a level that was comparable with that of vaccinated COVID‐19 convalescents except for BA.4/5. Avidity of RBD‐binding antibodies was also significantly increased in naïve individuals after the third dose, indicating an association between affinity maturation and cross neutralization of VoC. These results suggest that at least three antigenic stimuli by infection or vaccination with ancestral SARS‐CoV‐2 sequences are required to induce high avidity cross‐neutralizing antibodies. Nevertheless, the circulation of new subvariants such as BA.4/5 with partial resistance to neutralization will have to be closely monitored and eventually consider for future vaccine developments.
Currently, the majority of the population has been vaccinated against COVID‐19 and/or has experienced SARS‐CoV‐2 infection either before or after vaccination. The immunological response to repeated ...episodes of infections is not completely clear. We measured SARS‐CoV‐2 specific neutralization titers by a pseudovirus assay after BA.1 infection and RBD‐specific immunoglobulin G (IgG), immunoglobulin A (IgA), and immunoglobulin M (IgM) in a cohort of COVID‐19 uninfected and triple vaccinated individuals (breakthrough infection group, BTI) as compared with those previously infected by SARS‐CoV‐2 (reinfection group, REI) who underwent identical vaccination schedule. SARS‐CoV‐2 specific neutralizing response after BA.1 infection was significantly higher in the BTI group as compared with the REI. Furthermore, neutralization titers in REI were not significant different from convalescent non reinfected controls. RBD‐specific IgG and IgA, but not IgM, were also significantly higher in BTI as compared with REI. Our results show that the first episode of SARS‐CoV‐2 infection induces a significant increase in neutralizing titers in triple vaccinated individuals and that previous SARS‐CoV‐2 infection compromise significantly the neutralization response induced by reinfection, even by divergent SARS‐CoV‐2 variants and at least up to 2 years postinfection, suggesting a fundamental limitation in inducing effective booster through the intranasal route in previously infected individuals.
Streptococcus suis is an emerging zoonotic agent. Human infection is associated with occupational exposure to swine. Affected persons are usually, but not always, healthy (1,2). Immunosuppressive ...conditions can predispose persons to S. suis infection, and cancer has classically been associated as a risk factor for S. suis infection (1,2). Nevertheless, the actual number of reported cases is low (27). We describe a severe case of S. suis infection in a man who had not been exposed to swine but for whom disseminated cancer was diagnosed 5 months after the infection.
Objectives The observed higher incidence of pyogenic vertebral osteomyelitis (PVO) may entail an increasing number of patients with no microbiologic diagnosis. The true incidence of these cases, how ...exhaustive the etiologic diagnostic efforts must be, and the usefulness of an empirical antibiotic therapy are not well defined. Methods Retrospective analysis of all cases of vertebral osteomyelitis in our center (1991-2009) and retrospective analysis of cases of PVO (2005-2009). Clinical data, diagnostic procedures, treatment, and outcome were reviewed. A comparative analysis between microbiologically confirmed PVO (MCPVO) and probable PVO (PPVO) was performed. Results Increasing incidence of PVO (+0.047 episodes/100,000 inhabitants-year). During the last decade, there was an increase of PPVO (+0.059 episodes/100,000 inhabitants-year) with stable incidence of MCPVO. During 2005-2009, there were 72 patients 47 (65%) MCPVO and 25 (35%) PPVO. 60% men; mean age was 66 years. Bacteremia was found in 59%. Computed tomographic guided vertebral biopsy, positive in 7/36 (19%), was more successful among patients with bacteremia. Among MCPVO, there was an increasing proportion of less virulent bacteria. Cases of MCPVO presented more frequently with sepsis, fever, and high acute-phase reactants, and PPVO cases were mostly treated with oral fluoroquinolones plus rifampin. No differences were found between both groups in outcome (93% success, 22% sequelae). Conclusions An epidemiologic change of PVO is suggested by a higher incidence of PPVO and the isolation of less virulent microorganisms among MCPVO. In this setting, the availability of an oral and effective empirical antibiotic therapy may challenge an exhaustive prosecution of the etiology.
The incidence of prosthetic joint infection (PJI) is expected to increase in the coming years. PJI has serious consequences for patients, and high costs for the health system. The complexity of these ...infections makes it necessary to organize the vast quantity of information published in the last several years. The indications for the choice of a given surgical strategy and the corresponding antimicrobial therapy are specifically reviewed. The authors selected clinically relevant questions and then reviewed the available literature in order to give recommendations according to a pre-determined level of scientific evidence. The more controversial aspects were debated, and the final composition was agreed at an ad hoc meeting. Before its final publication, the manuscript was made available online in order that all SEIMC members were able to read it and make comments and suggestions.
This reprint brings together a group of articles that were published as a Special Issue on prosthetic joint infection in the journal Antibiotics. They cover various aspects of risk factors and ...prevention, medical and surgical treatment, and outcomes of prosthetic joint infections.
Abstract Objective To analyze the clinical features, microbiological spectrum, diagnostic procedures and outcomes in native joint pyogenic arthritis among non-intravenous drug users. Methods We ...collected all microbiologically proved cases of infectious arthritis at our hospital between 1992 and 2013. Patients with prosthetic joint infection were excluded, as were patients with non-pyogenic arthritis and intravenous drug users. Results We identified 268 patients; the mean age was 61 ± 14.7 years and 62% were men. The incidence increased over the period of study. In 188 patients (70%), one or more underlying medical illnesses were found. The mean symptom duration was 8.9 ± 9.5 days. Globally, 311 affected joints were found, 232 (75%) involving peripheral joints and 79 (25%) axial joints. Staphylococci (55%) and Streptococci (29%) were the predominant microorganisms. Blood cultures were positive in 78% (173/223) of the cases. In 81 patients (30%), one or more concomitant infectious processes were found. Antimicrobial therapy was prescribed 4–8 weeks in most cases, and surgical drainage was performed in 65% of patients. Four patients relapsed and 23 (8%) died. Conclusions The prevalence of pyogenic native joint arthritis in non-intravenous drug users is increasing, frequently affecting old patients with underlying medical conditions. Although large joints are the most frequently compromised, the involvement of axial joints is a relevant feature that has not been recognized in other series. Staphylococci and Streptococci are the main causative agents. Bacteremia and concomitant infectious processes are frequent complications. Diagnostic delay and mortality continue to be important concerns.
While tuberculosis remains a significant global health concern, prosthetic joint infections (PJIs) caused by members of the
complex are exceptionally rare. Our objective is to perform a retrospective ...search of new cases of this disease and analyze all cases available in the literature of tuberculous PJIs, aiming to detect factors that may influence patient outcomes.
The ESGIAI and ESGMYC study groups were used to collect information on non-published cases of tuberculous prosthetic joint infections (PJIs). Additionally, a literature review of all published cases of tuberculous PJIs was conducted. All identified cases in the retrospective study and in the literature review were merged and included in the statistical analysis, involving both univariate and multivariate analyses.
Fifteen previously unreported cases of tuberculous prosthetic joint infections (PJIs) from four countries were detailed. Among them, ten patients were female, with a median age of 76 years. The hip was affected in 13 cases. Seven patients experienced co-infection with another microorganism. Treatment approaches varied, with 13 patients undergoing implant removal, one treated with DAIR (debridement, antibiotics, and implant retention), and one case was treated with an unknown treatment method. All patients received antibiotic therapy and achieved a cure. The literature review that was conducted detected 155 published cases. Univariate analysis revealed a statistical significance for previous tuberculosis, joint, and no importance of surgery for cure.
Tuberculous prosthetic joint infection (PJI) is a rare condition, typically presenting as a localized chronic infection. Antibiotic treatment is essential for the management of these patients, but neither surgical treatment nor duration of treatment seems to have importance in the outcome.
Prosthetic joint infections are considered difficult to treat they needing aggressive surgery and long antimicrobial treatments. However, the exact duration of these therapies has been established ...empirically. In the last years, several studies have explored the possibility of reducing the length of treatment in this setting, with conflicting results. In this narrative review, we critically appraise the published evidence, considering the different surgical approaches (implant retention DAIR and one-step and two-step exchange procedures) separately. In patients managed with DAIR, usually treated for at least 12 weeks, a large, randomized trial failed to show that 6 weeks were non-inferior. However, another randomized clinical trial supports the use of 8 weeks, as long as the surgical conditions are favorable and antibiotics with good antibiofilm activity can be administered. In patients managed with a two-step exchange procedure, usually treated during 6 weeks, a randomized clinical trial showed the efficacy of a 4-week course of antimicrobials. Also, the use of local antibiotics may allow the use of even shorter treatments. Finally, in the case of one-step exchange procedures, there is a trend towards reducing the length of therapy, and the largest randomized clinical trial supports the use of 6 weeks of therapy.
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