How to Handle Concomitant Asymptomatic Prosthetic Joints During an Episode of Hematogenous Periprosthetic Joint Infection, a Multicenter Analysis

BACKGROUND

Prosthetic joints are at risk of becoming infected during an episode of bacteremia, especially during Staphylocococcus aureus bacteremia. However, it is unclear how often asymptomatic periprosthetic joint infection (PJI) occurs, and whether additional diagnostics should be considered.

METHODS

In this multicenter study, we retrospectively analyzed a cohort of patients with a late acute (hematogenous) PJI between 2005-2015 who had concomitant prosthetic joints in situ. Patients without at least 1 year of follow-up were excluded.

RESULTS

We included 91 patients with a hematogenous PJI and 108 concomitant prosthetic joints. The incident PJI was most frequently caused by Staphylococcus aureus (43%), followed by streptococci (26%) and Gram-negative rods (18%). Of 108 concomitant prosthetic joints, 13 were symptomatic, of which 10 were subsequently diagnosed as a second PJI. Of the 95 asymptomatic prosthetic joints, 1 PJI developed during the follow-up period and was classified as a "missed" PJI at the time of bacteremia with S. aureus (1.1%). Infected prosthetic joints were younger than the noninfected ones in 67% of cases, and prosthetic knees were affected more often than prosthetic hips (78%).

CONCLUSIONS

During an episode of hematogenous PJI, concomitant asymptomatic prosthetic joints have a very low risk of being infected, and additional diagnostic work-up for these joints is not necessary.

A Large Multicenter Prospective Study of Community-Onset Healthcare Associated Bacteremic Urinary Tract Infections in the Era of Multidrug Resistance: Even Worse than Hospital Acquired Infections?

INTRODUCTION

Healthcare-associated (HCA) infections represent a growing public health problem. The aim of this study was to compare community-onset healthcare associated (CO-HCA) bacteremic urinary tract infections (BUTI) and hospital-acquired (HA)-BUTI with special focus on multidrug resistances (MDR) and outcomes.

METHODS

ITUBRAS-project is a prospective multicenter cohort study of patients with HCA-BUTI. All consecutive hospitalized adult patients with CO-HCA-BUTI or HA-BUTI episode were included in the study. Exclusion criteria were: patients < 18 years old, non-hospitalized patients, bacteremia from another source or primary bacteremia, non-healthcare-related infections and infections caused by unusual pathogens of the urinary tract. The main outcome variable was 30-day all-cause mortality with day 1 as the first day of positive blood culture. Logistic regression was used to analyze factors associated with clinical cure at hospital discharge and with receiving inappropriate initial antibiotic treatment. Cox regression was used to evaluate 30-day all-cause mortality.

RESULTS

Four hundred forty-three episodes were included, 223 CO-HCA-BUTI. Patients with CO-HCA-BUTI were older (p < 0.001) and had more underlying diseases (p = 0.029) than those with HA-BUTI. The severity of the acute illness (Pitt score) was also higher in CO-HCA-BUTI (p = 0.026). Overall, a very high rate of MDR profiles (271/443, 61.2%) was observed, with no statistical differences between groups. In multivariable analysis, inadequate empirical treatment was associated with MDR profile (aOR 3.35; 95% CI 1.77-6.35), Pseudomonas aeruginosa (aOR 2.86; 95% CI 1.27-6.44) and Charlson index (aOR 1.11; 95% CI 1.01-1.23). Mortality was not associated with the site of acquisition of the infection or the presence of MDR profile. However, in the logistic regression analyses patients with CO-HCA-BUTI (aOR 0.61; 95% CI 0.40-0.93) were less likely to present clinical cure.

CONCLUSION

The rate of MDR infections was worryingly high in our study. No differences in MDR rates were found between CO-HCA-BUTI and HA-BUTI, in the probability of receiving inappropriate empirical treatment or in 30-day mortality. However, CO-HCA-BUTIs were associated with worse clinical cure.

Mural Endocarditis: The GAMES Registry Series and Review of the Literature

INTRODUCTION

Mural infective endocarditis (MIE) is a rare type of endovascular infection. We present a comprehensive series of patients with mural endocarditis.

METHODS

Patients with infectious endocarditis (IE) from 35 Spanish hospitals were prospectively included in the GAMES registry between 2008 and 2017. MIEs were compared to non-MIEs. We also performed a literature search for cases of MIE published between 1979 and 2019 and compared them to the GAMEs series.

RESULTS

Twenty-seven MIEs out of 3676 IEs were included. When compared to valvular IE (VIE) or device-associated IE (DIE), patients with MIE were younger (median age 59 years, p < 0.01). Transplantation (18.5% versus 1.6% VIE and 2% DIE, p < 0.01), hemodialysis (18.5% versus 4.3% VIE and 4.4% DIE, p = 0.006), catheter source (59.3% versus 9.7% VIE and 8.8% DIE, p < 0.01) and Candida etiology (22.2% versus 2% DIE and 1.2% VIE, p < 0.01) were more common in MIE, whereas the Charlson Index was lower (4 versus 5 in non-MIE, p = 0.006). Mortality was similar. MIE from the literature shared many characteristics with MIE from GAMES, although patients were younger (45 years vs. 56 years, p < 0.001), the Charlson Index was lower (1.3 vs. 4.3, p = 0.0001), catheter source was less common (13.9% vs. 59.3%) and there were more IVDUs (25% vs. 3.7%). S. aureus was the most frequent microorganism (50%, p = 0.035). Systemic complications were more common but mortality was similar.

CONCLUSION

MIE is a rare entity. It is often a complication of catheter use, particularly in immunocompromised and hemodialysis patients. Fungal etiology is common. Mortality is similar to other IEs.

Combination versus monotherapy as definitive treatment for Pseudomonas aeruginosa bacteraemia: a multicentre retrospective observational cohort study

BACKGROUND

Pseudomonas aeruginosa bacteraemia is a common and serious infection. No consensus exists regarding whether definitive combination therapy is superior to monotherapy. We aimed to evaluate the impact of combination therapy on mortality.

METHODS

This was a multicentre retrospective study (nine countries, 25 centres), including 1277 patients with P. aeruginosa bacteraemia during 2009-15. We evaluated the association between β-lactam plus aminoglycoside or quinolone combination therapy versus β-lactam monotherapy and mortality. The primary outcome was 30 day all-cause mortality. Univariate and multivariate Cox regression analyses were conducted, introducing combination as a time-dependent variable. Propensity score was conducted to adjust for confounding for choosing combination therapy over monotherapy.

RESULTS

Of 1119 patients included, 843 received definitive monotherapy and 276 received combination therapy (59% aminoglycoside and 41% quinolone). Mortality at 30 days was 16.9% (189/1119) and was similar between combination (45/276; 16.3%) and monotherapy (144/843; 17.1%) groups (P = 0.765). In multivariate Cox regression, combination therapy was not associated with reduced mortality (HR 0.98, 95% CI 0.64-1.53). No advantage in terms of clinical failure, microbiological failure or recurrent/persistent bacteraemia was demonstrated using combination therapy. Likewise, adverse events and resistance development were similar for the two regimens.

CONCLUSIONS

In this retrospective cohort, no mortality advantage was demonstrated using combination therapy over monotherapy for P. aeruginosa bacteraemia. Combination therapy did not improve clinical or microbiological failure rates, nor affect adverse events or resistance development. Our finding of no benefit with combination therapy needs confirmation in well-designed randomized controlled trials.

Not all COVID-19 pandemic waves are alike

OBJECTIVE

We aimed to assess differences in patients' profiles in the first two surges of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Barcelona, Spain.

METHODS

We prospectively collected data from all adult patients with SARS-CoV-2 infection diagnosed at the Hospital de la Santa Creu i Sant Pau, Barcelona, Spain. All the patients were diagnosed through nasopharyngeal swab PCR. The first surge spanned from 1st March to 13th August 2020, while surge two spanned from 14th August to 8th December 2020.

RESULTS

There were 2479 and 852 patients with microbiologically proven SARS-CoV-2 infection in surges one and two, respectively. Patients from surge two were significantly younger (median age 52 (IQR 35) versus 59 (40) years, respectively, p < 0.001), had fewer comorbidities (379/852, 44.5% versus 1237/2479, 49.9%, p 0.007), and there was a shorter interval between onset of symptoms and diagnosis (median 3 (5) versus 4 (5) days, p < 0.001). All-cause in-hospital mortality significantly decreased for both the whole population (24/852, 2.8% versus 218/2479, 8.8%, p < 0.001) and hospitalized patients (20/302, 6.6% versus 206/1570, 13.1%, p 0.012). At adjusted logistic regression analysis, predictors of in-hospital mortality were older age (per year, adjusted odds ratio (aOR) 1.079, 95%CI 1.063-1.094), male sex (aOR 1.476, 95%CI 1.079-2.018), having comorbidities (aOR 1.414, 95%CI 0.934-2.141), ICU admission (aOR 3.812, 95%CI 1.875-7.751), mechanical ventilation (aOR 2.076, 95%CI 0.968-4.454), and coronavirus disease 2019 (COVID-19) during surge one (with respect to surge two) (aOR 2.176, 95%CI 1.286-3.680).

CONCLUSIONS

First-wave SARS-CoV-2-infected patients had a more than two-fold higher in-hospital mortality than second-wave patients. The causes are likely multifactorial.

Identification and validation of clinical phenotypes with prognostic implications in patients admitted to hospital with COVID-19: a multicentre cohort study

BACKGROUND

The clinical presentation of COVID-19 in patients admitted to hospital is heterogeneous. We aimed to determine whether clinical phenotypes of patients with COVID-19 can be derived from clinical data, to assess the reproducibility of these phenotypes and correlation with prognosis, and to derive and validate a simplified probabilistic model for phenotype assignment. Phenotype identification was not primarily intended as a predictive tool for mortality.

METHODS

In this study, we used data from two cohorts: the COVID-19@Spain cohort, a retrospective cohort including 4035 consecutive adult patients admitted to 127 hospitals in Spain with COVID-19 between Feb 2 and March 17, 2020, and the COVID-19@HULP cohort, including 2226 consecutive adult patients admitted to a teaching hospital in Madrid between Feb 25 and April 19, 2020. The COVID-19@Spain cohort was divided into a derivation cohort, comprising 2667 randomly selected patients, and an internal validation cohort, comprising the remaining 1368 patients. The COVID-19@HULP cohort was used as an external validation cohort. A probabilistic model for phenotype assignment was derived in the derivation cohort using multinomial logistic regression and validated in the internal validation cohort. The model was also applied to the external validation cohort. 30-day mortality and other prognostic variables were assessed in the derived phenotypes and in the phenotypes assigned by the probabilistic model.

FINDINGS

Three distinct phenotypes were derived in the derivation cohort (n=2667)-phenotype A (516 [19%] patients), phenotype B (1955 [73%]) and phenotype C (196 [7%])-and reproduced in the internal validation cohort (n=1368)-phenotype A (233 [17%] patients), phenotype B (1019 [74%]), and phenotype C (116 [8%]). Patients with phenotype A were younger, were less frequently male, had mild viral symptoms, and had normal inflammatory parameters. Patients with phenotype B included more patients with obesity, lymphocytopenia, and moderately elevated inflammatory parameters. Patients with phenotype C included older patients with more comorbidities and even higher inflammatory parameters than phenotype B. We developed a simplified probabilistic model (validated in the internal validation cohort) for phenotype assignment, including 16 variables. In the derivation cohort, 30-day mortality rates were 2·5% (95% CI 1·4-4·3) for patients with phenotype A, 30·5% (28·5-32·6) for patients with phenotype B, and 60·7% (53·7-67·2) for patients with phenotype C (log-rank test p<0·0001). The predicted phenotypes in the internal validation cohort and external validation cohort showed similar mortality rates to the assigned phenotypes (internal validation cohort: 5·3% [95% CI 3·4-8·1] for phenotype A, 31·3% [28·5-34·2] for phenotype B, and 59·5% [48·8-69·3] for phenotype C; external validation cohort: 3·7% [2·0-6·4] for phenotype A, 23·7% [21·8-25·7] for phenotype B, and 51·4% [41·9-60·7] for phenotype C).

INTERPRETATION

Patients admitted to hospital with COVID-19 can be classified into three phenotypes that correlate with mortality. We developed and validated a simplified tool for the probabilistic assignment of patients into phenotypes. These results might help to better classify patients for clinical management, but the pathophysiological mechanisms of the phenotypes must be investigated.

FUNDING

Instituto de Salud Carlos III, Spanish Ministry of Science and Innovation, and Fundación SEIMC/GeSIDA.

Sarilumab (IL-6R antagonist) in critically ill patients with cytokine release syndrome by SARS-CoV2

Blocking IL-6 pathways with sarilumab, a fully human anti-IL-6R antagonist may potentially curb the inflammatory storm of SARS-CoV2. In the present emergency scenario, we used "off-label" sarilumab in 5 elderly patients in life-threatening condition not candidates to further active measures. We suggest that sarilumab can modulate severe COVID-19-associated Cytokine Release Syndrome.

Prosthetic Shoulder Joint Infection by Cutibacterium acnes: Does Rifampin Improve Prognosis? A Retrospective, Multicenter, Observational Study

This retrospective, multicenter observational study aimed to describe the outcomes of surgical and medical treatment of C. acnes-related prosthetic joint infection (PJI) and the potential benefit of rifampin-based therapies. Patients with C. acnes-related PJI who were diagnosed and treated between January 2003 and December 2016 were included. We analyzed 44 patients with C. acnes-related PJI (median age, 67.5 years (IQR, 57.3-75.8)); 75% were men. The majority (61.4%) had late chronic infection according to the Tsukayama classification. All patients received surgical treatment, and most antibiotic regimens (43.2%) included β-lactam. Thirty-four patients (87.17%) were cured; five showed relapse. The final outcome (cure vs. relapse) showed a nonsignificant trend toward higher failure frequency among patients with previous prosthesis (OR: 6.89; 95% CI: 0.80-58.90) or prior surgery and infection (OR: 10.67; 95% IC: 1.08-105.28) in the same joint. Patients treated with clindamycin alone had a higher recurrence rate (40.0% vs. 8.8%). Rifampin treatment did not decrease recurrence in patients treated with β-lactams. Prior prosthesis, surgery, or infection in the same joint might be related to recurrence, and rifampin-based combinations do not seem to improve prognosis. Debridement and implant retention appear a safe option for surgical treatment of early PJI.

Effectiveness and safety of intravenous tocilizumab to treat COVID-19-associated hyperinflammatory syndrome: Covizumab-6 observational cohort

Although the starting event in COVID-19 is a viral infection some patients present with an over-exuberant inflammatory response, leading to acute lung injury (ALI) and adult respiratory distress syndrome (ARDS). Since IL-6 plays a critical role in the inflammatory response, we assessed the efficacy and safety of tocilizumab (TCZ) in this single-centre, observational study in all Covid-19 in-patient with a proven SARS-CoV-2 rapidly progressing infection to prevent ALI and ARDS. 104 patients with COVID-19 treated with TCZ had a lower mortality rate (5·8%) compared with the regional mortality rate (11%), hospitalized patient's mortality (10%), and slightly lower than hospitalized patients treated with our standard of care alone (6%). We found that TCZ rapidly decreased acute phase reactants, ferritin and liver release of proteins. D-Dimer decreased slowly. We did not observe specific safety concerns. Early administration of IL6-R antagonists in COVID-19 patients with impending hyperinflammatory response, may be safe and effective treatment to prevent, ICU admission and further complications.

Implant Removal in the Management of Prosthetic Joint Infection by Staphylococcus aureus: Outcome and Predictors of Failure in a Large Retrospective Multicenter Study

OBJECTIVES

To compare the characteristics and outcomes of cases with acute prosthetic joint infection (PJI; early post-surgical or hematogenous) by Staphylococcus aureus managed with implant removal (IRm) or debridement and retention (DAIR). To analyze the outcomes of all cases managed with IRm (initially or after DAIR failure).

METHODS

Retrospective, multicenter, cohort study of PJI by S. aureus (2003-2010). Overall failure included mortality within 60 days since surgery and local failure due to staphylococcal persistence/relapse.

RESULTS

499 cases, 338 initially managed with DAIR, 161 with IRm. Mortality was higher in acute PJI managed initially with IRm compared to DAIR, but not associated with the surgical procedure, after propensity score matching. Underlying conditions, hemiarthroplasty, and methicillin-resistant S. aureus were risk factors for mortality. Finally, 249 cases underwent IRm (88 after DAIR failure); overall failure was 15.6%. Local failure (9.3%) was slightly higher in cases with several comorbidities, but independent of previous DAIR, type of IRm, and rifampin treatment.

CONCLUSIONS

In a large multicenter study of S. aureus PJI managed with IRm, failure was low, but mortality significant, especially in cases with acute PJI and underlying conditions, but not associated with the IRm itself. Rifampin efficacy was limited in this setting.

Executive summary of the Consensus Document of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and of the Spanish Association of Surgeons (AEC) in antibiotic prophylaxis in surgery

Antibiotic prophylaxis in surgery is one of the most effective measures for preventing surgical site infection, although its use is frequently inadequate and may even increase the risk of infection, toxicities and bacterial resistance. As a result of advances in surgical techniques and the emergence of multidrug-resistant organisms, the current guidelines for prophylaxis need to be revised. La Sociedad Española de Enfermedades Infecciosas (Spanish Society of Infectious Diseases and Clinical Microbiology) (SEIMC) together with the Asociación Española de Cirujanos (Spanish Association of Surgeons) (AEC) have revised and updated the recommendations for antibiotic prophylaxis to adapt them to any type of surgical intervention and to current epidemiology. This document gathers together the recommendations on antimicrobial prophylaxis in the various procedures, with doses, duration, prophylaxis in special patient groups, and in epidemiological settings of multidrug resistance to facilitate standardized management and the safe, effective and rational use of antibiotics in elective surgery.

Prevalence of Colorectal Neoplasms Among Patients With Enterococcus faecalis Endocarditis in the GAMES Cohort (2008-2017)

OBJECTIVE

To investigate the rate of colorectal neoplasms (CRNs) in patients who have Enterococcus faecalis infective endocarditis (EFIE) with available colonoscopies and to assess whether this is associated with the identification of a focus the infection.

PATIENTS AND METHODS

Retrospective analysis of data from a prospective multicenter study involving 35 centers who are members of the Grupo de Apoyo para el Manejo de la Endocarditis en España [Support Group for the Management of Infective Endocarditis in Spain] cohort. A specific set of queries regarding information on colonoscopy and histopathology of colorectal diseases was sent to each participating center. Four-hundred sixty-seven patients with EFIE were included from January 1, 2008, to December 31, 2017, from whom data on colonoscopy performance and results were available in 411 patients.

RESULTS

One hundred forty-two (34.5%) patients had a colonoscopy close to the EFIE episode. The overall rate of colorectal diseases was 70.4% (100 of 142), whereas the prevalence of CRN (advanced adenomas and colorectal carcinoma) was 14.8% (21 of 142), with no significant differences between the group of EFIE of unknown focus and that with an identified focus.

CONCLUSION

Our study adds to prior evidence suggesting a much higher rate of CRN among patients with EFIE than in the general population of the same age and sex. In addition, our findings suggest that this phenomenon might take place both in EFIE with an unknown and an identified source of infection.

Executive summary of the Consensus Document of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and of the Spanish Association of Surgeons (AEC) in antibiotic prophylaxis in surgery

Antibiotic prophylaxis in surgery is one of the most effective measures for preventing surgical site infection, although its use is frequently inadequate and may even increase the risk of infection, toxicities and antimicrobial resistance. As a result of advances in surgical techniques and the emergence of multidrug-resistant organisms, the current guidelines for prophylaxis need to be revised. The Sociedad Española de Enfermedades Infecciosas (Spanish Society of Infectious Diseases and Clinical Microbiology) (SEIMC) together with the Asociación Española de Cirujanos (Spanish Association of Surgeons) (AEC) have revised and updated the recommendations for antibiotic prophylaxis in surgery to adapt them to any type of surgical intervention and to current epidemiology. This document gathers together the recommendations on antimicrobial prophylaxis in the various procedures, with doses, duration, prophylaxis in special patient groups, and in epidemiological settings of multidrug resistance to facilitate standardized management and the safe, effective and rational use of antibiotics in elective surgery.

Intraoperative Bacterial Contamination and Activity of Different Antimicrobial Prophylaxis Regimens in Primary Knee and Hip Replacement

Surgical antimicrobial prophylaxis (SAP) is important for the prevention of prosthetic joint infections (PJIs) and must be effective against the microorganisms most likely to contaminate the surgical site. Our aim was to compare different SAP regimens (cefazolin, cefuroxime, or vancomycin, alone or combined with gentamicin) in patients undergoing total knee (TKA) and hip (THA) arthroplasty. In this preclinical exploratory analysis, we analyzed the results of intraoperative sample cultures, the ratio of plasma antibiotic levels to the minimum inhibitory concentrations (MICs) for bacteria isolated at the surgical wound and ATCC strains, and serum bactericidal titers (SBT) against the same microorganisms. A total of 132 surgical procedures (68 TKA, 64 THA) in 128 patients were included. Cultures were positive in 57 (43.2%) procedures (mostly for coagulase-negative staphylococci and Cutibacterium spp.); the rate was lower in the group of patients receiving combination SAP (adjusted OR 0.475, CI95% 0.229-0.987). The SAP regimens evaluated achieved plasma levels above the MICs in almost all of intraoperative isolates (93/94, 98.9%) and showed bactericidal activity against all of them (SBT range 1:8-1:1024), although SBTs were higher in patients receiving cefazolin and gentamicin-containing regimens. The potential clinical relevance of these findings in the prevention of PJIs remains to be determined.

Do Prosthetic Joint Infections Worsen the Functional Ambulatory Outcome of Patients with Joint Replacements? A Retrospective Matched Cohort Study

OBJECTIVES

To assess the effect on the functional ambulatory outcome of postoperative joint infection (PJI) cured at the first treatment attempt versus not developing PJI in patients with hip and knee prostheses.

METHODS

In a single-hospital retrospectively matched cohort study, each patient with PJI between 2007 and 2016 was matched on age, sex, type of prosthesis and year of implantation with two other patients with uninfected arthroplasties. The definition of a PJI cure included infection eradication, no further surgical procedures, no PJI-related mortality and no suppressive antibiotics. Functional ambulatory status evaluated one year after the last surgery was classified into four simple categories: able to walk without assistance, able to walk with one crutch, able to walk with two crutches, and unable to walk. Patients with total hip arthroplasties (THA), total knee arthroplasties (TKA) and partial hip arthroplasty (PHA) were analysed separately.

RESULTS

A total of 109 PJI patients (38 TKA, 41 THA, 30 PHA) and 218 non-PJI patients were included. In a model adjusted for clinically relevant variables, PJI was associated with a higher risk of needing an assistive device for ambulation (vs. walking without aid) among THA (adjusted odds ratio (OR) 3.10, 95% confidence interval (95% CI) 1.26-7.57; p = 0.014) and TKA patients (OR 5.40, 95% CI 2.12-13.67; p < 0.001), and with requiring two crutches to walk or being unable to walk (vs. walking unaided or with one crutch) among PHA patients (OR 3.05, 95% CI 1.01-9.20; p = 0.047).

CONCLUSIONS

Ambulatory outcome in patients with hip and knee prostheses with postoperative PJI is worse than in patients who do not have PJI.

Characteristics and predictors of death among 4035 consecutively hospitalized patients with COVID-19 in Spain

OBJECTIVES

To analyse the characteristics and predictors of death in hospitalized patients with coronavirus disease 2019 (COVID-19) in Spain.

METHODS

A retrospective observational study was performed of the first consecutive patients hospitalized with COVID-19 confirmed by real-time PCR assay in 127 Spanish centres until 17 March 2020. The follow-up censoring date was 17 April 2020. We collected demographic, clinical, laboratory, treatment and complications data. The primary endpoint was all-cause mortality. Univariable and multivariable Cox regression analyses were performed to identify factors associated with death.

RESULTS

Of the 4035 patients, male subjects accounted for 2433 (61.0%) of 3987, the median age was 70 years and 2539 (73.8%) of 3439 had one or more comorbidity. The most common symptoms were a history of fever, cough, malaise and dyspnoea. During hospitalization, 1255 (31.5%) of 3979 patients developed acute respiratory distress syndrome, 736 (18.5%) of 3988 were admitted to intensive care units and 619 (15.5%) of 3992 underwent mechanical ventilation. Virus- or host-targeted medications included lopinavir/ritonavir (2820/4005, 70.4%), hydroxychloroquine (2618/3995, 65.5%), interferon beta (1153/3950, 29.2%), corticosteroids (1109/3965, 28.0%) and tocilizumab (373/3951, 9.4%). Overall, 1131 (28%) of 4035 patients died. Mortality increased with age (85.6% occurring in older than 65 years). Seventeen factors were independently associated with an increased hazard of death, the strongest among them including advanced age, liver cirrhosis, low age-adjusted oxygen saturation, higher concentrations of C-reactive protein and lower estimated glomerular filtration rate.

CONCLUSIONS

Our findings provide comprehensive information about characteristics and complications of severe COVID-19, and may help clinicians identify patients at a higher risk of death.

The four horsemen of a viral Apocalypse: The pathogenesis of SARS-CoV-2 infection (COVID-19)

The pathogenesis of coronavirus disease 2019 (COVID-19) may be envisaged as the dynamic interaction between four vicious feedback loops chained or happening at once. These are the viral loop, the hyperinflammatory loop, the non-canonical renin-angiotensin system (RAS) axis loop, and the hypercoagulation loop. Severe acute respiratory syndrome (SARS)-coronavirus (CoV)-2 lights the wick by infecting alveolar epithelial cells (AECs) and downregulating the angiotensin converting enzyme-2 (ACE2)/angiotensin (Ang-1-7)/Mas1R axis. The viral feedback loop includes evading the host's innate response, uncontrolled viral replication, and turning on a hyperactive adaptative immune response. The inflammatory loop is composed of the exuberant inflammatory response feeding back until exploding in an actual cytokine storm. Downregulation of the ACE2/Ang-(1-7)/Mas1R axis leaves the lung without a critical defense mechanism and turns the scale to the inflammatory side of the RAS. The coagulation loop is a hypercoagulable state caused by the interplay between inflammation and coagulation in an endless feedback loop. The result is a hyperinflammatory and hypercoagulable state producing acute immune-mediated lung injury and eventually, adult respiratory distress syndrome.

Ceftazidime, Carbapenems, or Piperacillin-tazobactam as Single Definitive Therapy for Pseudomonas aeruginosa Bloodstream Infection: A Multisite Retrospective Study

BACKGROUND

The optimal antibiotic regimen for Pseudomonas aeruginosa bacteremia is controversial. Although β-lactam monotherapy is common, data to guide the choice between antibiotics are scarce. We aimed to compare ceftazidime, carbapenems, and piperacillin-tazobactam as definitive monotherapy.

METHODS

A multinational retrospective study (9 countries, 25 centers) including 767 hospitalized patients with P. aeruginosa bacteremia treated with β-lactam monotherapy during 2009-2015. The primary outcome was 30-day all-cause mortality. Univariate and multivariate, including propensity-adjusted, analyses were conducted introducing monotherapy type as an independent variable.

RESULTS

Thirty-day mortality was 37/213 (17.4%), 42/210 (20%), and 55/344 (16%) in the ceftazidime, carbapenem, and piperacillin-tazobactam groups, respectively. Type of monotherapy was not significantly associated with mortality in either univariate, multivariate, or propensity-adjusted analyses (odds ratio [OR], 1.14; 95% confidence interval [CI], 0.52-2.46, for ceftazidime; OR, 1.3; 95% CI, 0.67-2.51, for piperacillin-tazobactam, with carbapenems as reference in propensity adjusted multivariate analysis; 542 patients). No significant difference between antibiotics was demonstrated for clinical failure, microbiological failure, or adverse events. Isolation of P. aeruginosa with new resistance to antipseudomonal drugs was significantly more frequent with carbapenems (36/206 [17.5%]) versus ceftazidime (25/201 [12.4%]) and piperacillin-tazobactam (28/332 [8.4%] (P = .007).

CONCLUSIONS

No significant difference in mortality, clinical, and microbiological outcomes or adverse events was demonstrated between ceftazidime, carbapenems, and piperacillin-tazobactam as definitive treatment of P. aeruginosa bacteremia. Higher rates of resistant P. aeruginosa after patients were treated with carbapenems, along with the general preference for carbapenem-sparing regimens, suggests using ceftazidime or piperacillin-tazobactam for treating susceptible infection.

Pathogenesis of Staphylococcus epidermidis in prosthetic joint infections: Can identification of virulence genes differentiate between infecting and commensal strains?

BACKGROUND

Staphylococcus epidermidis is a commensal of human skin flora and a frequent causative microorganism in prosthetic joint infections (PJIs). To date, no single marker has been identified to distinguish infecting strains from commensal S. epidermidis populations.

AIM

We aimed to find possible genetic markers to distinguish between the two populations.

METHODS

We analyzed 50 S. epidermidis strains from patients with PJIs, 50 from skin of healthy individuals (commensal strains) and 17 from the surgical field of patients undergoing primary arthroplasty. In these three groups we studied the antimicrobial susceptibility profile, sequence type, biofilm formation, and virulence factors. Strains from the surgical field have not been compared previously with strains from the other two groups.

FINDINGS

S. epidermidis strains from PJI patients were significantly more antibiotic resistant than commensal strains and surgical field strains. A wide variety of sequences types was found in commensal and surgical field strains. The predominant sequence type was ST2 and it was only present in PJI strains (44%). Differences in biofilm production did not differ between populations. Virulence genes sdrF and bhp, the complete ica operon, and the insertion sequence IS256 were significantly predominant in PJI strains. In contrast, embp and hld genes and the mobile element ACME were more prevalent in commensal strains. Surgical field strains could be a valid control group to discriminate between infecting and commensal strains.

CONCLUSION

A combination of characteristic features can differentiate between infecting and commensal S. epidermidis strains in PJI, while a single marker cannot.

Characteristics and outcome of spontaneous bacterial meningitis in patients with diabetes mellitus

BACKGROUND

Studies on bacterial meningitis in diabetics patients versus non-diabetics are scarce. In patients with diabetes, bacterial meningitis may have a different presentation, etiology and course. We analyzed and compared the characteristics and outcome of spontaneous BM in adult patients with and without diabetes mellitus (DM).

METHODS

We performed a single-center, prospective observational cohort study, conducted between 1982 and 2017, in a tertiary university hospital in Barcelona (Spain). The primary outcome measure was in-hospital mortality.

RESULTS

We evaluated 715 episodes of bacterial meningitis; 106 patients (15%) had diabetes mellitus. Patients with diabetes were older (median 67 [IQR 17] vs 49 [IQR 40] years, p <  0.001) and more often had a Charlson comorbidity score of ≥3 (40% vs 15%, p <  0.001). Neck stiffness (56% vs 75%, p <  0.001), headache (41% vs 78%) p <  0.001), nausea and/or vomiting (32% vs 56% p < 0.001), and rash (12% vs 26%, p = 0.007) were less frequent in diabetics, whereas altered mental status was more common. Streptococcus pneumoniae and Listeria meningitis were the most common etiologic agents (24 and 18%, respectively). Listeria was more frequent (18% vs. 10%, p = 0.033), whereas meningococcal meningitis was less frequent (10% vs 32%, p < 0.001). Overall mortality was higher in patients with diabetes (26% vs 16%, p = 0.025) concerning non-diabetics.

CONCLUSIONS

Patients with bacterial meningitis and diabetes mellitus are older, have more comorbidities, and higher mortality. S. pneumoniae and L. monocytogenes are the predominant pathogens, Listeria being more common, whereas Neisseria meningitidis is significantly less frequent than in non-diabetics.

Recommendations of the Spanish Antibiogram Committee (COESANT) for selecting antimicrobial agents and concentrations for in vitro susceptibility studies using automated systems

Automated antimicrobial susceptibility testing devices are widely implemented in clinical microbiology laboratories in Spain, mainly using EUCAST (European Committee on Antimicrobial Susceptibility Testing) breakpoints. In 2007, a group of experts published recommendations for including antimicrobial agents and selecting concentrations in these systems. Under the patronage of the Spanish Antibiogram Committee (Comité Español del Antibiograma, COESANT) and the Study Group on Mechanisms of Action and Resistance to Antimicrobial Agents (GEMARA) from the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), and aligned with the Spanish National Plan against Antimicrobial Resistance (PRAN), a group of experts have updated this document. The main modifications from the previous version comprise the inclusion of new antimicrobial agents, adaptation of the ranges of concentrations to cover the EUCAST breakpoints and epidemiological cut-off values (ECOFFs), and the inference of new resistance mechanisms. This proposal should be considered by different manufacturers and users when designing new panels or cards. In addition, recommendations for selective reporting are also included. With this approach, the implementation of EUCAST breakpoints will be easier, increasing the quality of antimicrobial susceptibility testing data and their microbiological interpretation. It will also benefit epidemiological surveillance studies as well as the clinical use of antimicrobials aligned with antimicrobial stewardship programs.

Suppressive antibiotic therapy in prosthetic joint infections: a multicentre cohort study

OBJECTIVES

The aim was to describe the effectiveness of suppressive antibiotic treatment (SAT) in routine clinical practice when used in situations in which removal of a prosthetic implant is considered essential for the eradication of an infection, and it cannot be performed.

METHODS

This was a descriptive retrospective and multicentre cohort study of prosthetic joint infection (PJI) cases managed with SAT. SAT was considered to have failed if a fistula appeared or persisted, if debridement was necessary, if the prosthesis was removed due to persistence of the infection or if uncontrolled symptoms were present.

RESULTS

In total, 302 patients were analysed. Two hundred and three of these patients (67.2%) received monotherapy. The most commonly used drugs were tetracyclines (39.7% of patients) (120/302) and cotrimoxazole (35.4% of patients) (107/302). SAT was considered successful in 58.6% (177/302) of the patients (median time administered, 36.5 months; IQR 20.75-59.25). Infection was controlled in 50% of patients at 5 years according to Kaplan-Meier analysis. Resistance development was documented in 15 of 65 (23.1%) of the microbiologically documented cases. SAT failure was associated with age <70 years (sub-hazard ratio (SHR) 1.61, 95% CI 1.1-2.33), aetiology other than Gram-positive cocci (SHR 1.56, 95% CI 1.09-2.27) and location of the prosthesis in the upper limb (SHR 2.4, 95% CI 1.5-3.84). SAT suspension was necessary due to adverse effects in 17 of 302 patients (5.6%).

CONCLUSIONS

SAT offers acceptable results for patients with PJI when surgical treatment is not performed or when it fails to eradicate the infection.

A Contemporary Picture of Enterococcal Endocarditis

BACKGROUND

Enterococcal endocarditis (EE) is a growing entity in Western countries. However, quality data from large studies is lacking.

OBJECTIVES

The purpose of this study was to describe the characteristics and analyze the prognostic factors of EE in the GAMES cohort.

METHODS

This was a post hoc analysis of a prospectively collected cohort of patients from 35 Spanish centers from 2008 to 2016. Characteristics and outcomes of 516 cases of EE were compared with those of 3,308 cases of nonenterococcal endocarditis (NEE). Logistic regression and Cox proportional hazards regression analysis were performed to investigate risk factors for in-hospital and 1-year mortality, as well as relapses.

RESULTS

Patients with EE were significantly older; more frequently presented chronic lung disease, chronic heart failure, prior endocarditis, and degenerative valve disease; and had higher median age-adjusted Charlson score. EE more frequently involved the aortic valve and prosthesis (64.3% vs. 46.7%; p < 0.001; and 35.9% vs. 28.9%; p = 0.002, respectively) but less frequently pacemakers/defibrillators (1.5% vs. 10.5%; p < 0.001), and showed higher rates of acute heart failure (45% vs. 38.3%; p = 0.005). Cardiac surgery was less frequently performed in EE (40.7% vs. 45.9%; p = 0.024). No differences in in-hospital and 1-year mortality were found, whereas relapses were significantly higher in EE (3.5% vs. 1.7%; p = 0.035). Increasing Charlson score, LogEuroSCORE, acute heart failure, septic shock, and paravalvular complications were risk factors for mortality, whereas prior endocarditis was protective and persistent bacteremia constituted the sole risk factor for relapse.

CONCLUSIONS

Besides other baseline and clinical differences, EE more frequently affects prosthetic valves and less frequently pacemakers/defibrillators. EE presents higher rates of relapse than NEE.

From CLSI to EUCAST, a necessary step in Spanish laboratories

The Spanish Antibiogram Committee (Comité Español del Antibiograma, COESANT) presents in this document a simple "roadmap" or decalogue of recommendations, with a view to facilitating the transition from the Clinical and Laboratory Standards Institute (CLSI) to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) antimicrobial susceptibility testing regulations to the Clinical Microbiology Spanish laboratories that still use the CLSI guidelines. The objectives are to adapt the closer European regulations to the Spanish clinical and epidemiological reality and to fully implement the EUCAST recommendations in all microbiology laboratories in Spain.

Risk factors for mortality among patients with Pseudomonas aeruginosa bacteraemia: a retrospective multicentre study

This study aimed to evaluate risk factors for 30-day mortality among hospitalised patients with Pseudomonas aeruginosa bacteraemia, a highly fatal condition. A retrospective study was conducted between 1 January 2009 and 31 October 2015 in 25 centres (9 countries) including 2396 patients. Univariable and multivariable analyses of risk factors were conducted for the entire cohort and for patients surviving ≥48 h. A propensity score for predictors of appropriate empirical therapy was introduced into the analysis. Of the 2396 patients, 636 (26.5%) died within 30 days. Significant predictors (odds ratio and 95% confidence interval) of mortality in the multivariable analysis included patient-related factors: age (1.02, 1.01-1.03); female sex (1.34, 1.03-1.77); bedridden functional capacity (1.99, 1.24-3.21); recent hospitalisation (1.43, 1.07-1.92); concomitant corticosteroids (1.33, 1.02-1.73); and Charlson comorbidity index (1.05, 1.01-1.93). Infection-related factors were multidrug-resistant Pseudomonas (1.52, 1.15-2.1), non-urinary source (2.44, 1.54-3.85) and Sequential Organ Failure Assessment (SOFA) score (1.27, 1.18-1.36). Inappropriate empirical therapy was not associated with increased mortality (0.81, 0.49-1.33). Among 2135 patients surviving ≥48 h, hospital-acquired infection (1.59, 1.21-2.09), baseline endotracheal tube (1.63, 1.13-2.36) and ICU admission (1.53, 1.02-2.28) were additional risk factors. Risk factors for mortality among patients with P. aeruginosa were mostly irreversible. Early appropriate empirical therapy was not associated with reduced mortality. Further research should be conducted to explore subgroups that may not benefit from broad-spectrum antipseudomonal empirical therapy. Efforts should focus on prevention of infection, mainly hospital-acquired infection and multidrug-resistant pseudomonal infection.

Pulmonary Thrombosis or Embolism in a Large Cohort of Hospitalized Patients With Covid-19

Objective: We set out to analyze the incidence and predictive factors of pulmonary embolism (PE) in hospitalized patients with Covid-19. Methods: We prospectively collected data from all consecutive patients with laboratory-confirmed Covid-19 admitted to the Hospital de la Santa Creu i Sant Pau, a university hospital in Barcelona, between March 9 and April 15, 2020. Patients with suspected PE, according to standardized guidelines, underwent CT pulmonary angiography (CTPA). Results: A total of 1,275 patients with Covid-19 were admitted to hospital. CTPA was performed on 76 inpatients, and a diagnosis of PE was made in 32 (2.6% [95%CI 1.7-3.5%]). Patients with PE were older, and they exhibited lower PaO₂:FiO₂ ratios and higher levels of D-dimer and C-reactive protein (CRP). They more often required admission to ICU and mechanical ventilation, and they often had longer hospital stays, although in-hospital mortality was no greater than in patients without PE. High CRP and D-dimer levels at admission (≥150 mg/L and ≥1,000 ng/ml, respectively) and a peak D-dimer ≥6,000 ng/ml during hospital stay were independent factors associated with PE. Prophylactic low molecular weight heparin did not appear to prevent PE. Increased CRP levels correlated with increased D-dimer levels and both correlated with a lower PaO₂:FiO₂. Conclusions: The 2.6% incidence of PE in Covid-19 hospitalized patients is clearly high. Higher doses of thromboprophylaxis may be required to prevent PE, particularly in patients at increased risk, such as those with high levels of CRP and D-dimer at admission. These findings should be validated in future studies.

Outpatient Parenteral Antibiotic Treatment for Infective Endocarditis: A Prospective Cohort Study From the GAMES Cohort

BACKGROUND

Outpatient parenteral antibiotic treatment (OPAT) has proven efficacious for treating infective endocarditis (IE). However, the 2001 Infectious Diseases Society of America (IDSA) criteria for OPAT in IE are very restrictive. We aimed to compare the outcomes of OPAT with those of hospital-based antibiotic treatment (HBAT).

METHODS

Retrospective analysis of data from a multicenter, prospective cohort study of 2000 consecutive IE patients in 25 Spanish hospitals (2008-2012) was performed.

RESULTS

A total of 429 patients (21.5%) received OPAT, and only 21.7% fulfilled IDSA criteria. Males accounted for 70.5%, median age was 68 years (interquartile range [IQR], 56-76), and 57% had native-valve IE. The most frequent causal microorganisms were viridans group streptococci (18.6%), Staphylococcus aureus (15.6%), and coagulase-negative staphylococci (14.5%). Median length of antibiotic treatment was 42 days (IQR, 32-54), and 44% of patients underwent cardiac surgery. One-year mortality was 8% (42% for HBAT; P < .001), 1.4% of patients relapsed, and 10.9% were readmitted during the first 3 months after discharge (no significant differences compared with HBAT). Charlson score (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.04-1.42; P = .01) and cardiac surgery (OR, 0.24; 95% CI, .09-.63; P = .04) were associated with 1-year mortality, whereas aortic valve involvement (OR, 0.47; 95% CI, .22-.98; P = .007) was the only predictor of 1-year readmission. Failing to fulfill IDSA criteria was not a risk factor for mortality or readmission.

CONCLUSIONS

OPAT provided excellent results despite the use of broader criteria than those recommended by IDSA. OPAT criteria should therefore be expanded.

Epidemiology and Treatment of Multidrug-Resistant and Extensively Drug-Resistant Pseudomonas aeruginosa Infections

In recent years, the worldwide spread of the so-called high-risk clones of multidrug-resistant or extensively drug-resistant (MDR/XDR) Pseudomonas aeruginosa has become a public health threat. This article reviews their mechanisms of resistance, epidemiology, and clinical impact and current and upcoming therapeutic options. In vitro and in vivo treatment studies and pharmacokinetic and pharmacodynamic (PK/PD) models are discussed. Polymyxins are reviewed as an important therapeutic option, outlining dosage, pharmacokinetics and pharmacodynamics, and their clinical efficacy against MDR/XDR P. aeruginosa infections. Their narrow therapeutic window and potential for combination therapy are also discussed. Other "old" antimicrobials, such as certain β-lactams, aminoglycosides, and fosfomycin, are reviewed here. New antipseudomonals, as well as those in the pipeline, are also reviewed. Ceftolozane-tazobactam has clinical activity against a significant percentage of MDR/XDR P. aeruginosa strains, and its microbiological and clinical data, as well as recommendations for improving its use against these bacteria, are described, as are those for ceftazidime-avibactam, which has better activity against MDR/XDR P. aeruginosa, especially strains with certain specific mechanisms of resistance. A section is devoted to reviewing upcoming active drugs such as imipenem-relebactam, cefepime-zidebactam, cefiderocol, and murepavadin. Finally, other therapeutic strategies, such as use of vaccines, antibodies, bacteriocins, anti-quorum sensing, and bacteriophages, are described as future options.

Timing of implant-removal in late acute periprosthetic joint infection: A multicenter observational study

OBJECTIVES

We evaluated the treatment outcome in late acute (LA) periprosthetic joint infections (PJI) treated with debridement and implant retention (DAIR) versus implant removal.

METHODS

In a large multicenter study, LA PJIs of the hip and knee were retrospectively evaluated. Failure was defined as: PJI related death, prosthesis removal or the need for suppressive antibiotic therapy. LA PJI was defined as acute symptoms <3 weeks in patients more than 3 months after the index surgery and with a history of normal joint function.

RESULTS

445 patients were included, comprising 340 cases treated with DAIR and 105 cases treated with implant removal (19% one-stage revision (n = 20), 74.3% two-stage revision (n = 78) and 6.7% definitive implant removal (n = 7). Overall failure in patients treated with DAIR was 45.0% (153/340) compared to 24.8% (26/105) for implant removal (p < 0.001). Difference in failure rate remained after 1:1 propensity-score matching. A preoperative CRIME80-score ≥3 (OR 2.9), PJI caused by S. aureus (OR 1.8) and implant retention (OR 3.1) were independent predictors for failure in the multivariate analysis.

CONCLUSION

DAIR is a viable surgical treatment for most patients with LA PJI, but implant removal should be considered in a subset of patients, especially in those with a CRIME80-score ≥3.

Mitral valve repair in infective endocarditis is not inferior to valve replacement: results from a Spanish nationwide prospective registry

INTRODUCTION

Infective endocarditis (IE) still carries high morbidity and mortality and frequently requires surgery. The benefit of mitral valve repair (MVr) in the setting of IE is yet to be proven. The goal of this study was to assess the results of MVr in patients with IE after a minimum follow-up of 1 year.

METHODS

This study is based on a Spanish nationwide prospective registry that included patients operated on for native mitral valve IE. The collaborating Institutions pooled their pre-, peri-, and postoperative data into the database of the GAMES group [Grupo de Apoyo al Manejo de la EndocarditiS (Group for support and management of infective endocarditis)].

RESULTS

Data from 27 hospitals were recorded and 3524 cases of active IE identified between 2008 and 2016. There were 1513 cases of mitral IE, of which 898 involved native valves. Of these, 437 patients underwent surgical treatment, and 369 completed the 1-year follow-up. The valve was repaired in 68 cases (18.4%). Preoperative groups were comparable (EuroSCORE MVr 7.7 vs MVR 8.0; p = ns). Mortality in the repair group was inferior to that in the replacement group (16.2% vs 27.2%, p = 0.058). At 1 year, mortality remained higher in the replacement group: 3.7% vs 2.9%. Relapse of the infection was slightly more frequent in the repair group (7.1% vs 3.7%; p = ns), although this did not lead to higher rates of reintervention (MVr/MVR: 2.9% vs 4.9%).

CONCLUSION

MVr is an attractive option for specific patients with IE and does not seem to negatively impact on relapses.

Role of age and comorbidities in mortality of patients with infective endocarditis

PURPOSE

The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality.

METHODS

Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk.

RESULTS

A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32-3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39-1.88),and non-performed surgery (HR:1.64;95% CI:11.16-1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality.

CONCLUSION

There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group.

Antimicrobial management of Tropheryma whipplei endocarditis: the Spanish Collaboration on Endocarditis (GAMES) experience

OBJECTIVES

Tropheryma whipplei has been detected in 3.5% of the blood culture-negative cases of endocarditis in Spain. Experience in the management of T. whipplei endocarditis is limited. Here we report the long-term outcome of the treatment of previously reported patients who were diagnosed with infective endocarditis (IE) caused by T. whipplei from the Spanish Collaboration on Endocarditis-Grupo de Apoyo al Manejo de la Endocarditis Infecciosa en España (GAMES) and discuss potential options for antimicrobial therapy for IE caused by T. whipplei.

PATIENTS AND METHODS

Seventeen patients with T. whipplei endocarditis were recruited between 2008 and 2014 in 25 Spanish hospitals. Patients were classified according to the therapeutic regimen: ceftriaxone and trimethoprim/sulfamethoxazole, doxycycline + hydroxychloroquine and other treatment options.

RESULTS

Follow-up data were obtained from 14 patients. The median follow-up was 46.5 months. All patients completed the antibiotic treatment prescribed, with a median duration of 13 months. Six patients were treated with ceftriaxone and trimethoprim/sulfamethoxazole (median duration 13 months), four with doxycycline + hydroxychloroquine (median duration 13.8 months) and four with other treatment options (median duration 22.3 months). The follow-up after the end of the treatments was between 5 and 84 months (median 24 months).

CONCLUSIONS

All treatment lines were effective and well tolerated. Therapeutic failures were not detected during the treatment. None of the patients died or experienced a relapse during the follow-up. Only six patients received antibiotic treatment in accordance with guidelines. These data suggest that shorter antimicrobial treatments could be effective.

Proceedings from the 2018 International Consensus Meeting on Orthopedic Infections: management of periprosthetic shoulder infection

The Second International Consensus Meeting on Orthopedic Infections was held in Philadelphia, Pennsylvania, in July 2018. A multidisciplinary team of international experts from all 9 subspecialties of orthopedic surgery and allied fields of infectious disease, microbiology, and epidemiology was assembled to form the International Consensus Group. The following consensus proceedings from the International Consensus Meeting involve 30 questions pertaining to the management of periprosthetic shoulder infection.

The Different Microbial Etiology of Prosthetic Joint Infections according to Route of Acquisition and Time after Prosthesis Implantation, Including the Role of Multidrug-Resistant Organisms

The aim of our study was to characterize the etiology of prosthetic joint infections (PJIs)-including multidrug-resistant organisms (MDRO)-by category of infection. A multicenter study of 2544 patients with PJIs was performed. We analyzed the causative microorganisms according to the Tsukayama's scheme (early postoperative, late chronic, and acute hematogenous infections (EPI, LCI, AHI) and "positive intraoperative cultures" (PIC)). Non-hematogenous PJIs were also evaluated according to time since surgery: <1 month, 2-3 months, 4-12 months, >12 months. AHIs were mostly caused by Staphylococcus aureus (39.2%) and streptococci (30.2%). EPIs were characterized by a preponderance of virulent microorganisms (S. aureus, Gram-negative bacilli (GNB), enterococci), MDROs (24%) and polymicrobial infections (27.4%). Conversely, coagulase-negative staphylococci (CoNS) and Cutibacterium species were predominant in LCIs (54.5% and 6.1%, respectively) and PICs (57.1% and 15.1%). The percentage of MDROs isolated in EPIs was more than three times the percentage isolated in LCIs (7.8%) and more than twice the proportion found in AHI (10.9%). There was a significant decreasing linear trend over the four time intervals post-surgery for virulent microorganisms, MDROs, and polymicrobial infections, and a rising trend for CoNS, streptococci and Cutibacterium spp. The observed differences have important implications for the empirical antimicrobial treatment of PJIs.

Rhodomyrtone decreases Staphylococcus aureus SigB activity during exponentially growing phase and inhibits haemolytic activity within membrane vesicles

Sigma factor B (SigB) controls the expression of Staphylococcus aureus genes including virulence factors and plays a role in the bacterial secretion system through membrane vesicle production. Inhibition of SigB could attenuate SigB dependent virulence and secretion system. The objective of this study was to determine the effects of rhodomyrtone on SigB and virulence factors related to SigB. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values of rhodomyrtone against 67 clinical methicillin-resistant S. aureus isolates were 0.25-8 μg/ml, which were similar to those of vancomycin. Using luciferase gene fused to SigB dependent promoters of asp23, five time reduction in SigB activity was observed when the bacteria were treated with rhodomyrtone for 3 h. Rhodomyrtone significantly reduced SigB activity in a concentration dependent manner in exponentially growing cells (P < 0.05). In addition, sigB mutant was more sensitive towards increasing concentrations of rhodomyrtone than the wild type and yabJ-spoVG mutant. Rhodomyrtone at 0.625 μg/ml reduced the growth of sigB mutant by approximately 99%, compared with the yabJ-spoVG mutant and the wild type. Membrane vesicles were significantly reduced in the bacterial cells when treated with 0.5 × MIC rhodomyrtone (P < 0.05). Decreased haemolytic activity was detected within rhodomyrtone-treated membrane vesicles. The results indicated that rhodomyrtone inhibited S. aureus SigB activity during exponentially growing phase and inhibited haemolytic activity within membrane vesicles.

Multidrug-resistant and extensively drug-resistant Gram-negative prosthetic joint infections: Role of surgery and impact of colistin administration

Factors influencing treatment outcome of patients with Gram-negative bacterial (GNB) multidrug-resistant (MDR) and extensively drug-resistant (XDR) prosthetic joint infection (PJIs) were analysed. Data were collected (2000-2015) by 18 centres. Treatment success was analysed by surgery type for PJI, resistance (MDR/XDR) and antimicrobials (colistin/non-colistin) using logistic regression and survival analyses. A total of 131 patients (mean age 73.0 years, 35.9% male, 58.8% with co-morbidities) with MDR (n = 108) or XDR (n = 23) GNB PJI were assessed. The most common pathogens were Escherichia coli (33.6%), Pseudomonas aeruginosa (25.2%), Klebsiella pneumoniae (21.4%) and Enterobacter cloacae (17.6%). Pseudomonas aeruginosa predominated in XDR cases. Isolates were carbapenem-resistant (n = 12), fluoroquinolone-resistant (n = 63) and ESBL-producers (n = 94). Treatment outcome was worse in XDR versus MDR cases (P = 0.018). Success rates did not differ for colistin versus non-colistin in XDR cases (P = 0.657), but colistin was less successful in MDR cases (P = 0.018). Debridement, antibiotics and implant retention (DAIR) (n = 67) was associated with higher failure rates versus non-DAIR (n = 64) (OR = 3.57, 95% CI 1.68-7.58; P < 0.001). Superiority of non-DAIR was confirmed by Kaplan-Meir analysis (HR = 0.36, 95% CI 0.20-0.67) and remained unchangeable by time of infection (early/late), antimicrobial resistance (MDR/XDR) and antimicrobials (colistin/non-colistin) (Breslow-Day, P = 0.737). DAIR is associated with higher failure rates even in early MDR/XDR GNB PJIs versus implant removal. Colistin should be preserved for XDR cases as it is detrimental in MDR infections.

Clinical outcome and risk factors for failure in late acute prosthetic joint infections treated with debridement and implant retention

OBJECTIVES

Debridement, antibiotics and implant retention (DAIR) is the recommended treatment for all acute prosthetic joint infections (PJI), but its efficacy in patients with late acute (LA) PJI is not well described.

METHODS

Patients diagnosed with LA PJI between 2005 and 2015 were retrospectively evaluated. LA PJI was defined as the development of acute symptoms (≤ 3 weeks) occurring ≥ 3 months after arthroplasty. Failure was defined as: (i) the need for implant removal, (ii) infection related death, (iii) the need for suppressive antibiotic therapy and/or (iv) relapse or reinfection during follow-up.

RESULTS

340 patients from 27 centers were included. The overall failure rate was 45.0% (153/340). Failure was dominated by Staphylococcus aureus PJI (54.7%, 76/139). Significant independent preoperative risk factors for failure according to the multivariate analysis were: fracture as indication for the prosthesis (odds ratio (OR) 5.4), rheumatoid arthritis (OR 5.1), age above 80 years (OR 2.6), male gender (OR 2.0) and C-reactive protein > 150 mg/L (OR 2.0). Exchanging the mobile components during DAIR was the strongest predictor for treatment success (OR 0.35).

CONCLUSION

LA PJIs have a high failure rate. Treatment strategies should be individualized according to patients' age, comorbidity, clinical presentation and microorganism causing the infection.

Candida periprosthetic joint infection: A rare and difficult-to-treat infection

BACKGROUND

Candida periprosthetic joint infection (CPJI) is a rare, difficult-to-treat disease. The purpose of this study was to evaluate the clinical characteristics and outcomes of CPJI treated with various surgical and antifungal strategies.

METHODS

We conducted a multicenter retrospective study of all CPJI diagnosed between 2003 and 2015 in 16 Spanish hospitals.

RESULTS

Forty-three patients included: median age, 75 years, and median Charlson Comorbidity Index score, 4. Thirty-four (79.1%) patients had ≥1 risk factor for Candida infection. Most common causative species were C. albicans and C. parapsilosis. Thirty-five patients were evaluable for outcome: overall, treatment succeeded in 17 (48.6%) and failed in 18 (51.4%). Success was 13/20 (67%) in patients with prosthesis removal and 4/15 (27%) with debridement and prosthesis retention (p = 0.041). All 3 patients who received an amphotericin B-impregnated cement spacer cured. In the prosthesis removal group, success was 5/6 (83%) with an antibiofilm regimen and 8/13 (62%) with azoles (p = 0.605). In the debridement and prosthesis retention group, success was 3/10 (30%) with azoles and 1/5 (20%) with antibiofilm agents. Therapeutic failure was due to relapse in 9 patients, need for suppressive treatment in 5, persistent infection in 2, and CPJI-related death in 2; overall attributable mortality was 6%.

CONCLUSIONS

CPJI is usually a chronic disease in patients with comorbidities and risk factors for Candida infection. Treatment success is low, and prosthesis removal improves outcome. Although there is insufficient evidence that use of antifungals with antibiofilm activity has additional benefits, our experience indicates it may be recommendable.

Gentamicin may have no effect on mortality of staphylococcal prosthetic valve endocarditis

PURPOSE

To analyze the influence of adding gentamicin to a regimen consisting of β-lactam or vancomycin plus rifampicin on survival in patients suffering from Staphylococcal prosthetic valve endocarditis (SPVE).

METHODS

From January 2008 to September 2016, 334 patients with definite SPVE were attended in the participating hospitals. Ninety-four patients (28.1%) received treatment based on β-lactam or vancomycin plus rifampicin and were included in the study. Variables were analyzed which related to patient survival during admission, including having received treatment with gentamicin.

RESULTS

Seventy-seven (81.9%) were treated with cloxacillin (or vancomycin) plus rifampicin plus gentamicin, and 17 patients (18.1%) received the same regimen without gentamicin. The causative microorganism was Staphylococcus aureus in 40 cases (42.6%) and coagulase-negative staphylococci in 54 cases (57.4%). Overall, 40 patients (42.6%) died during hospital admission, 33 patients (42.9%) in the group receiving gentamicin and 7 patients in the group that did not (41.2%, P = 0.899). Worsening renal function was observed in 42 patients (54.5%) who received gentamicin and in 9 patients (52.9%) who did not (p = 0.904). Heart failure as a complication of endocarditis (OR: 4.58; CI 95%: 1.84-11.42) and not performing surgery when indicated (OR: 2.68; CI 95%: 1.03-6.94) increased mortality. Gentamicin administration remained unrelated to mortality (OR: 1.001; CI 95%: 0.29-3.38) in the multivariable analysis.

CONCLUSIONS

The addition of gentamicin to a regimen containing vancomycin or cloxacillin plus rifampicin in SPVE was not associated to better outcome.

Infective Endocarditis in Patients With Bicuspid Aortic Valve or Mitral Valve Prolapse

BACKGROUND

There is little information concerning infective endocarditis (IE) in patients with bicuspid aortic valve (BAV) or mitral valve prolapse (MVP). Currently, IE antibiotic prophylaxis (IEAP) is not recommended for these conditions.

OBJECTIVES

This study sought to describe the clinical and microbiological features of IE in patients with BAV and MVP and compare them with those of IE patients with and without IEAP indication, to determine the potential benefit of IEAP in these conditions.

METHODS

This analysis involved 3,208 consecutive IE patients prospectively included in the GAMES (Grupo de Apoyo al Manejo de la Endocarditis infecciosa en España) registry at 31 Spanish hospitals. Patients were classified as high-risk IE with IEAP indication (high-risk group; n = 1,226), low- and moderate-risk IE without IEAP indication (low/moderate-risk group; n = 1,839), and IE with BAV (n = 54) or MVP (n = 89).

RESULTS

BAV and MVP patients had a higher incidence of viridans group streptococci IE than did high-risk group and low/moderate-risk group patients (35.2% and 39.3% vs. 12.1% and 15.0%, respectively; all p < 0.01). A similar pattern was seen for IE from suspected odontologic origin (14.8% and 18.0% vs. 5.8% and 6.0%; all p < 0.01). BAV and MVP patients had more intracardiac complications than did low/moderate-risk group (50% and 47.2% vs. 30.6%, both p < 0.01) patients and were similar to high-risk group patients.

CONCLUSIONS

IE in patients with BAV and MVP have higher rates of viridans group streptococci IE and IE from suspected odontologic origin than in other IE patients, with a clinical profile similar to that of high-risk IE patients. Our findings suggest that BAV and MVP should be classified as high-risk IE conditions and the case for IEAP should be reconsidered.

Prosthetic Valve Candida spp. Endocarditis: New Insights Into Long-term Prognosis-The ESCAPE Study

BACKGROUND

Prosthetic valve endocarditis caused by Candida spp. (PVE-C) is rare and devastating, with international guidelines based on expert recommendations supporting the combination of surgery and subsequent azole treatment.

METHODS

We retrospectively analyzed PVE-C cases collected in Spain and France between 2001 and 2015, with a focus on management and outcome.

RESULTS

Forty-six cases were followed up for a median of 9 months. Twenty-two patients (48%) had a history of endocarditis, 30 cases (65%) were nosocomial or healthcare related, and 9 (20%) patients were intravenous drug users. "Induction" therapy consisted mainly of liposomal amphotericin B (L-amB)-based (n = 21) or echinocandin-based therapy (n = 13). Overall, 19 patients (41%) were operated on. Patients <66 years old and without cardiac failure were more likely to undergo cardiac surgery (adjusted odds ratios [aORs], 6.80 [95% confidence interval [CI], 1.59-29.13] and 10.92 [1.15-104.06], respectively). Surgery was not associated with better survival rates at 6 months. Patients who received L-amB alone had a better 6-month survival rate than those who received an echinocandin alone (aOR, 13.52; 95% CI, 1.03-838.10). "Maintenance" fluconazole therapy, prescribed in 21 patients for a median duration of 13 months (range, 2-84 months), led to minor adverse effects.

CONCLUSION

L-amB induction treatment improves survival in patients with PVE-C. Medical treatment followed by long-term maintenance fluconazole may be the best treatment option for frail patients.

Genomics and Susceptibility Profiles of Extensively Drug-Resistant Pseudomonas aeruginosa Isolates from Spain

This study assessed the molecular epidemiology, resistance mechanisms, and susceptibility profiles of a collection of 150 extensively drug-resistant (XDR) Pseudomonas aeruginosa clinical isolates obtained from a 2015 Spanish multicenter study, with a particular focus on resistome analysis in relation to ceftolozane-tazobactam susceptibility. Broth microdilution MICs revealed that nearly all (>95%) of the isolates were nonsusceptible to piperacillin-tazobactam, ceftazidime, cefepime, aztreonam, imipenem, meropenem, and ciprofloxacin. Most of them were also resistant to tobramycin (77%), whereas nonsusceptibility rates were lower for ceftolozane-tazobactam (31%), amikacin (7%), and colistin (2%). Pulsed-field gel electrophoresis-multilocus sequence typing (PFGE-MLST) analysis revealed that nearly all of the isolates belonged to previously described high-risk clones. Sequence type 175 (ST175) was detected in all 9 participating hospitals and accounted for 68% (n = 101) of the XDR isolates, distantly followed by ST244 (n = 16), ST253 (n = 12), ST235 (n = 8), and ST111 (n = 2), which were detected only in 1 to 2 hospitals. Through phenotypic and molecular methods, the presence of horizontally acquired carbapenemases was detected in 21% of the isolates, mostly VIM (17%) and GES enzymes (4%). At least two representative isolates from each clone and hospital (n = 44) were fully sequenced on an Illumina MiSeq. Classical mutational mechanisms, such as those leading to the overexpression of the β-lactamase AmpC or efflux pumps, OprD inactivation, and/or quinolone resistance-determining regions (QRDR) mutations, were confirmed in most isolates and correlated well with the resistance phenotypes in the absence of horizontally acquired determinants. Ceftolozane-tazobactam resistance was not detected in carbapenemase-negative isolates, in agreement with sequencing data showing the absence of ampC mutations. The unique set of mutations responsible for the XDR phenotype of ST175 clone documented 7 years earlier were found to be conserved, denoting the long-term persistence of this specific XDR lineage in Spanish hospitals. Finally, other potentially relevant mutations were evidenced, including those in penicillin-binding protein 3 (PBP3), which is involved in β-lactam (including ceftolozane-tazobactam) resistance, and FusA1, which is linked to aminoglycoside resistance.

The Effect of Preoperative Antimicrobial Prophylaxis on Intraoperative Culture Results in Patients with a Suspected or Confirmed Prosthetic Joint Infection: a Systematic Review

Obtaining reliable cultures during revision arthroplasty is important to adequately diagnose and treat a prosthetic joint infection (PJI). The influence of antimicrobial prophylaxis on culture results remains unclear. Since withholding prophylaxis increases the risk for surgical site infections, clarification on this topic is critical. A systematic review was performed with the following research question: in patients who undergo revision surgery of a prosthetic joint, does preoperative antimicrobial prophylaxis affect the culture yield of intraoperative samples in comparison with nonpreoperative antimicrobial prophylaxis? Seven articles were included in the final analysis. In most studies, standard diagnostic culture techniques were used. In patients with a PJI, pooled analysis showed a culture yield of 88% (145/165) in the prophylaxis group versus 95% (344/362) in the nonprophylaxis group (P = 0.004). Subanalysis of patients with chronic PJIs showed positive cultures in 88% (78/89) versus 91% (52/57), respectively (P = 0.59). In patients with a suspected chronic infection, a maximum difference of 4% in culture yield between the prophylaxis and nonprophylaxis groups was observed. With the use of standard culture techniques, antimicrobial prophylaxis seems to affect cultures in a minority of patients. Along with the known risk of surgical site infections due to inadequate timing of antimicrobial prophylaxis, we discourage the postponement of prophylaxis until tissue samples are obtained in revision surgery. Future studies are necessary to conclude whether the small percentage of false-negative cultures after prophylaxis can be further reduced with the use of more-sensitive culture techniques, like sonication.