Prospective assessment of the frequency of and risk factors for bleeding events in patients treated with cefazolin.

PURPOSE: Major bleedings have been described with cefazolin. The objective was to determine the frequency of bleeding events in cefazolin-treated patients and to identify risk factors for these complications. METHODS: Monocenter prospective observational study of all consecutive cefazolin-treated patients. Patients benefited from a daily clinical assessment of bleedings and a twice-a-week blood sampling including hemostasis. Bleedings were classified according to the International Society on Thrombosis and Hemostasis classification: major, clinically relevant non-major bleedings (CRNMB) and minor bleedings. RESULTS: From September 2019 to July 2020, 120 patients were included, with a mean age of 59.4 (± 20.7) years; 70% of them (84/120) were men. At least 1 CRNMB or major bleeding were observed in 10% of the patients (12/120). Compared to patients with no or minor bleeding, patients with CRNMB or major bleeding were, upon start of cefazolin, more frequently hospitalized in an intensive care unit (7/12, 58.3%, vs. 12/108, 11.1%, P < 0.001, respectively) and receiving vitamin K antagonists (4/12, 33.3%, vs. 8/108, 7.4%, P = 0.019, respectively). After multivariate analysis, patients receiving vitamin K antagonists the day prior bleeding and/or treated for endocarditis were factors associated with an increased risk of CRNMB or major bleeding (odd ratio 1.36, confidence interval 95%, 1.06-1.76, P = 0.020 and 1.30, 1.06-1.61, P = 0.015, respectively). CONCLUSIONS: Bleeding events associated with cefazolin treatment are frequent. Close clinical monitoring should be performed for patients treated for endocarditis and/or receiving vitamin K antagonists. Hemostasis work-up could be restricted to these patients.

Efficacy of single antibiotic therapy versus antibiotic combination in implant-free staphylococcal post-surgical spinal infections: a retrospective observational study.

BACKGROUND: Post-surgical spinal infections (pSSIs) are a serious complication of spinal surgeries, with Staphylococcus spp. being one of the most prominent bacteria identified. Optimal antimicrobial therapy for staphylococcal spinal infections without spinal implants is not well documented. METHODS: This single center retrospective 7-year observational study described and compared the outcome (treatment failure or mortality rate one year after diagnosis) of 20 patients with staphylococcal-implant-free pSSI treated with single or combination antibiotics. RESULTS: Median duration of treatment was 40 days (IQR 38-42), with 6 days (IQR 5-7) on intravenous antibiotics and 34 days (IQR 30-36) on oral therapy. Four patients (20%) underwent new surgical debridement, all due to surgical failure, and 1 patient died within the first year without significant differences between both treatment group. CONCLUSION: This study raises the possibility of single antibiotic therapy for patients with implant-free post-surgical spinal infections due to Staphylococcus spp.

Analysis of in-patient evolution of Escherichia coli reveals potential links to relapse of bone and joint infections.

Bone and joint infections (BJIs) are difficult to treat and affect a growing number of patients, in which relapses are observed in 10-20% of the case. These relapses, which call for prolonged antibiotic treatment and increase resistance emergence risk, may originate from ill understood adaptation of the pathogen to the host. Here, we investigated three pairs of Escherichia coli strains from BJI cases and their relapses to unravel in-patient adaptation. Whole genome comparison presented evidence for positive selection and phenotypic characterization showed that biofilm formation remained unchanged, contrary to what is usually described in such cases. Although virulence was not modified, we identified the loss of two virulence factors contributing to immune system evasion in one of the studied strains. Other strategies, including global growth optimization and colicin production, likely allowed the strains to outcompete competitors. This work highlights the variety of strategies allowing in-patient adaptation in BJIs.

Frequency and factors associated with infusion-related local complications of vancomycin on peripheral venous catheters.

BACKGROUND: Vancomycin is a reference antibiotic against methicillin-resistant staphylococci. Its administration is associated with infusion-related local complications (IRLC). To reduce this risk, it has been proposed to increase vancomycin dilution in the IV bag and to perform continuous infusion using the volumetric pump. The aim of our study was to assess the safety of peripheral infusion of vancomycin with the volumetric pump. OBJECTIVES: To compare the frequency of IRLC between patients receiving vancomycin and those receiving ß-lactam (BL) antibiotics. Our secondary objective was to assess factors associated with the occurrence of IRLC. PATIENTS AND METHODS: We conducted a prospective observational study in a French tertiary hospital. Between February 2021 and November 2021, we included all patients receiving continuous infusions of vancomycin or BL through a peripherally inserted venous catheter (PIVC). The primary endpoint was the occurrence of IRLC on Day 1 (D1). RESULTS: We included 168 patients (56 vancomycin, 112 BL). At D1, 14 patients (25%) presented IRLC in the vancomycin group versus 11 patients (10%) in the BL group (P = 0.01). There was significantly more IRLC in the group receiving vancomycin at an infused concentration above 5 mg/mL than those receiving BL (8/15, 53.3% versus 11/112, 10%, respectively, P < 0.01). However, no significant difference was observed between patients receiving infused vancomycin concentration ≤5 mg/mL and patients receiving BL (P = 0.4). CONCLUSION: Our data support safe administration of vancomycin if infused at a concentration under 5 mg/mL, through the volumetric pump on PIVC.

Evaluating the heart valve tissue diffusion of amoxicillin in infective endocarditis: a pilot prospective observational non-comparative study.

OBJECTIVES: Treating patients with infective endocarditis (IE) due to streptococci and enterococci currently involves high-dosage antibiotics. Recent literature suggests a 30%-70% diffusion rate could be extrapolated to human heart valve tissue. The objective of this study was to evaluate the diffusion coefficient of amoxicillin in heart valve tissue of patients operated for IE. METHODS: Adult patients were prospectively included that underwent surgery at the European Hospital Georges Pompidou for IE due to streptococci and enterococci and had previous IV amoxicillin treatment. Plasma (taken 48 h preoperatively) and heart valve tissue amoxicillin concentrations were measured with a validated LC-MS/MS method. The MIC values of amoxicillin were measured for all available isolates. RESULTS: Seventeen patients were included. Eleven (64.7%) patients had native valve IE and six (35.3%) had prosthetic valve IE. Fourteen IE cases (82.4%) were due to streptococci, one (5.9%) was due to enterococci and two (11.8%) were Haemophilus spp, Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, Kingella kingae group infections. Median (IQR) amoxicillin dose administered was 10.5 (8.0-12.0) g/day corresponding to 138.2 (112.5-160.0) mg/kg/day. The median amoxicillin plasma concentrations pre-surgery and intra-tissular weighted concentrations were 31.9 (25.9-51.9) mg/L and 19.0 (7.9-31.4) µg/g, respectively. Median tissue/plasma concentration ratio was 0.47 (0.24-0.67), with a median amoxicillin plasma/MIC ratio of 487 (179-745), and median amoxicillin tissue/MIC ratio of 42 (14-116). CONCLUSIONS: With a significant diffusion coefficient, amoxicillin dosage in heart valve tissues showed a concentration/MIC ratio well above current recommendations for bactericidal activity. Our study suggests that lower doses can be considered for susceptible bacteria.

TIVAP-related infection due to Gram-negative aerobic bacilli: should TIVAP stay or should it go?

We aimed to describe the outcome of totally implantable venous-access port (TIVAP)-related infections due to Gram-negative aerobic bacilli (Pseudomonas aeruginosa and other Pseudomonas spp., Acinetobacter spp., and Stenotrophomonas maltophilia), or GNAB, and assess the safety of conservative treatment. We conducted a retrospective study in a French teaching hospital, from January 2016 to December 2020, including adult patients treated for TIVAP-related infection due to GNAB. Success of conservative treatment was defined as a functional TIVAP 3 months after infection with no recurrence. We performed a bivariate analysis and analyzed causes for treatment failure. We included 68 patients (53 TIVAP-related bloodstream infections, 11 TIVAP-related infections, and 4 probable TIVAP-related infections) due to GNAB, mostly P. aeruginosa (50/68, 74%). TIVAP removal was initially decided for 49/68 patients (72%). Among the 19/68 (28%) patients with conservative treatment (all for infections caused by P. aeruginosa), 5/19 (26%) had successful treatment, 7/19 (37%) experienced failure (without sepsis or septic shock), 6/19 (32%) died within 3 months without TIVAP removal and no signs of infection recurrence, and 1 patient had TIVAP removal as it was no longer required. TIVAP-related infections caused by GNAB frequently require TIVAP removal. Conservative treatment can be performed in selected patients with a non-complicated infection caused by P. aeruginosa, who can benefit from the continuation of antineoplastic chemotherapy or palliative care. Treatment failures were not associated with sepsis or septic shock.

Incidence of and risk factors for local complications of peripheral venous catheters in patients older than 70 years: Empirical research quantitative.

AIMS: To assess the incidence density of local complications of peripheral venous catheters in patients aged 70 years and older, to identify risk factors for local complications of peripheral venous catheters, to describe microbiological epidemiology and to assess the impact of complications on patient outcomes. DESIGN: Prospective, observational, single-centre study. METHODS: Patients 70 years and older admitted to the geriatric department of a teaching hospital in France between December 2019 and May 2020 were considered for inclusion if they had a peripheral venous catheter during their stay. Nurses checked the catheter insertion site three times a day for local complications; physicians ensured the follow-up of complications. The STROBE checklist was used in this prospective observational study. RESULTS: A total of 322 patients were included, with 849 peripheral venous catheters; the median age was 88 years and 182 (56.5%) were women. The incidence density of local complications was 50.5/1000 peripheral venous catheter-days. Risk factors for local complications on multivariate analysis were dressing replacement (OR 1.18), furosemide (OR 1.11) and vancomycin (OR 1.60) infusion, urinary continence (OR 1.09) and hematoma at the catheter insertion site (OR 1.15). Thirteen cellulitis and three abscesses were diagnosed. Occurrence of a local complication was associated with a 3-day increased duration of hospital stay (17 vs. 14 days). CONCLUSION: Risk factors for peripheral venous catheter local complications include urinary continence, furosemide or vancomycin infusion, hematoma at the peripheral venous catheter insertion site or dressing replacement. IMPLICATION FOR THE PATIENT CARE: Closer clinical monitoring may help reduce the occurrence of local peripheral venous catheters complication in patients 70 years and older. RELEVANCE TO CLINICAL PRACTICE: Patients at greater risk of peripheral venous catheter local complications deserve closer clinical monitoring or improved preventive measures, which may be beneficial to reduce the length of hospital stay. NO PATIENT OR PUBLIC CONTRIBUTION: The study was designed to describe risk factors for local complications of peripheral venous catheters in order to reinforce surveillance in this specific population by nurses and medical staffs. Patients had their peripheral venous catheter insertion site checked thrice a day by the nurse in charge as part of usual care. They, as service users, caregivers or members of the public, were not solicited for data collection, analysis, interpretation or preparation of the manuscript.

Nocardia Infections in Hematopoietic Cell Transplant Recipients: A Multicenter International Retrospective Study of the Infectious Diseases Working Party of the European Society for Blood and Marrow Transplantation.

BACKGROUND: Nocardiosis is rare after hematopoietic cell transplantation (HCT). Little is known regarding its presentation, management, and outcome in this population. METHODS: This retrospective international study reviewed nocardiosis episodes in HCT recipients (1/1/2000-31/12/2018; 135 transplant centers; 33 countries) and described their clinical, microbiological, radiological, and outcome characteristics. RESULTS: We identified 81 nocardiosis episodes in 74 allo- and 7 auto-HCT recipients. Nocardiosis occurred a median of 8 (IQR: 4-18) months post-HCT. The most frequently involved organs were lungs (70/81; 86%) and brain (30/81; 37%); 29 (36%) patients were afebrile; 46/81 (57%) had disseminated infections. The most common lung imaging findings were consolidations (33/68; 49%) or nodules (32/68; 47%); brain imaging findings were multiple brain abscesses (19/30; 63%). Ten of 30 (33%) patients with brain involvement lacked neurological symptoms. Fourteen of 48 (29%) patients were bacteremic. Nocardia farcinica was the most common among molecularly identified species (27%; 12/44). Highest susceptibility rates were reported to linezolid (45/45; 100%), amikacin (56/57; 98%), trimethoprim-sulfamethoxazole (57/63; 90%), and imipenem (49/57; 86%). One-year and last follow-up (IQR: 4-42.5 months) all-cause mortality were 40% (32/81) and 52% (42/81), respectively. In the multivariable analysis, underlying disease not in complete remission (HR: 2.81; 95% CI: 1.32-5.95) and prior bacterial infection (HR: 3.42; 95% CI: 1.62-7.22) were associated with higher 1-year all-cause mortality. CONCLUSIONS: Nocardiosis is a late post-HCT infection usually manifesting as a pulmonary disease with frequent dissemination, brain infection, and bacteremia. Brain imaging should be performed in HCT recipients with nocardiosis regardless of neurological symptoms. Overall mortality is high.

Targeted SARS-CoV-2 treatment is associated with decreased mortality in immunocompromised patients with COVID-19.

BACKGROUND: Little is known about targeted (antiviral or monoclonal antibody) anti-SARS-CoV-2 treatment in immunocompromised patients with COVID-19. OBJECTIVES: To assess the real-life efficacy and tolerance of targeted treatment of COVID-19 in immunocompromised patients. PATIENTS AND METHODS: Single-centre retrospective case series of immunocompromised patients with COVID-19 between December 2021 and March 2022. We recorded all cases of COVID-19 among immunocompromised patients treatment between 20 December 2021 and 15 March 2022. Choice of treatment was left to the physician's decision, according to internal treatment protocol, treatment availability and circulating variants. Main outcome was death from COVID-19 after no treatment or targeted treatment. RESULTS: Sixty-seven immunocompromised patients [38 male; median (IQR) age, 53 (43-63) years], with a median (IQR) follow-up of 60 (47-80) days. Ten patients did not receive any targeted treatment. Targeted treatment consisted of IV curative remdesivir (n = 22), sotrovimab (n = 16), tixagevimab/cilgavimab (n = 13) and casirivimab/imdevimab (n = 1). Ten patients (15%) presented severe COVID-19 and 2 (3%) died from Omicron COVID-19. Comparing patients who received targeted anti-SARS-CoV-2 treatment and no prophylaxis, (n = 42; 81%) with those who did not (n = 10; 19%), death rate was significantly lower in treated patients [n = 0 (0%) versus n = 2 (20%); P = 0.034]. No severe adverse events were reported among treated patients. Among 15 patients who received tixagevimab/cilgavimab as pre-exposure prophylaxis, 6 received an additional curative treatment and none died from COVID-19. CONCLUSIONS: Our results suggest that targeted COVID-19 treatment, including direct antivirals or monoclonal antibodies, is safe and efficient and could be proposed in high-risk immunocompromised patients.

In vitro study of factors influencing the duration of antimicrobial protection of antimicrobial-impregnated external ventricular drains.

BACKGROUND: In vitro and clinical studies assessing the duration of the protective activity of antimicrobial-impregnated external ventricular drains (AI-EVDs) gave conflicting results. OBJECTIVES: To identify factors associated with decreased antimicrobial activity of AI-EVDs that were not taken into account in previous in vitro models. METHODS: We performed in vitro experiments with Bactiseal™ AI-EVDs, under different conditions. Tested parameters were chosen to mimic conditions in which AI-EVDs are used: perfusion by saline (at different flow rates) or not perfused, dwelling medium (air, saline, saline+protein, lipid) and temperature. Antimicrobial activity was assessed by measurement of inhibitory diameters of a 0.5 cm portion of an AI-EVD (cut every 2 days) placed onto agar plates covered by a standardized Staphylococcus spp. inoculum (three different isolates). MS was used to measure concentrations of rifampicin and clindamycin after 48 h of dwelling. RESULTS: In univariate analysis, most of the tested factors were associated with reduced antimicrobial activity: liquid media (as compared with ambient air), perfusion whatever the rate flow (as compared with no perfusion) and presence of protein in the media. In multivariate analysis, dwelling in media (lipid or saline) was the most constantly associated with a reduction of inhibition diameters (P < 0.01), as compared with ambient air. After 48 h of dwelling, the clindamycin concentration was higher than 100 and 450 mg/L in saline and saline+BSA, respectively. CONCLUSIONS: The medium in which an AI-EVD is dwelling plays a significant role in the duration of AI-EVD activity. These results may explain conflicting results between clinical and in vitro studies.

Appropriateness of empirical antibiotic prescription for bloodstream infections in an emergency department from 2006 to 2018: impact of the spread of ESBL-producing Enterobacterales.

The spread of ESBL producers in the community may impact the management of patients with bloodstream infections (BSI) involving Enterobacterales in emergency departments. Thus, from 2006 to 2018, data for all BSI episodes involving Enterobacterales from the emergency department of a French teaching hospital were retrospectively included. Antimicrobial susceptibility test results and empirical antibiotic regimens were recorded. Treatment was considered as appropriate if all isolates were susceptible in vitro to at least one prescribed antibiotic. A total of 1369 BSI episodes in 1321 patients was included. Urinary tract infection was the main source of BSI (61%). The prevalence of ESBL producers increased from zero to 9.2/100 Enterobacterales BSI cases (p < 0.001), mainly Escherichia coli (6.9 cases/100 BSI in 2018); and no Klebsiella. Third-generation cephalosporins (3GC) were used most frequently (71.8%) and their use as monotherapy increased during the study period (p < 0.001). The rate of appropriate treatment decreased from 95.8 to 89.2% (p = 0.023). Appropriateness of treatment was greater using two drugs vs one (97.3% vs 89.3%, p < 0.001). Treatments with 3GC were appropriate in 92% and 98.3%, when used alone or with another antibiotic, respectively (p < 0.001). Among inappropriate treatments, 45% concerned 3GC, with 74.6% of them attributable to ESBL production. The spread of ESBL producers in the community had a direct impact on the rate of inappropriate empirical treatment. Local antimicrobial resistance monitoring is required to optimize the management of BSI in emergency departments.

Sera Neutralizing Activities Against Severe Acute Respiratory Syndrome Coronavirus 2 and Multiple Variants 6 Months After Hospitalization for Coronavirus Disease 2019.

BACKGROUND: Humoral response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurs within the first weeks after coronavirus disease 2019 (COVID-19). Those antibodies exert a neutralizing activity against SARS-CoV-2, whose evolution over time after COVID-19 as well as efficiency against novel variants are poorly characterized. METHODS: In this prospective study, sera of 107 patients hospitalized with COVID-19 were collected at 3 and 6 months postinfection. We performed quantitative neutralization experiments on top of high-throughput serological assays evaluating anti-spike (S) and anti-nucleocapsid (NP) immunoglobulin G (IgG). RESULTS: Levels of seroneutralization and IgG rates against the ancestral strain decreased significantly over time. After 6 months, 2.8% of the patients had a negative serological status for both anti-S and anti-NP IgG. However, all sera had a persistent and effective neutralizing effect against SARS-CoV-2. IgG levels correlated with seroneutralization, and this correlation was stronger for anti-S than for anti-NP antibodies. The level of seroneutralization quantified at 6 months correlated with markers of initial severity, notably admission to intensive care units and the need for mechanical invasive ventilation. In addition, sera collected at 6 months were tested against multiple SARS-CoV-2 variants and showed efficient neutralizing effects against the D614G, B.1.1.7, and P.1 variants but significantly weaker activity against the B.1.351 variant. CONCLUSIONS: Decrease in IgG rates and serological assays becoming negative did not imply loss of neutralizing capacity. Our results indicate a sustained humoral response against the ancestral strain and the D614G, B.1.1.7, and P.1 variants for at least 6 months in patients previously hospitalized for COVID-19. A weaker protection was, however, observed for the B.1.351 variant.

Management dilemmas in Nocardia brain infection.

PURPOSE OF REVIEW: Brain nocardiosis is a rare but severe infection mostly occurring among immunocompromised patients. In this review, we present recent data on this infection and address some of the common clinical dilemmas encountered in patients with brain nocardiosis. RECENT FINDINGS: Strategies used to approach a patient with suspected brain nocardiosis include the 'conservative strategy' (without early neurosurgery) and the 'neurosurgical strategy' (with early aspiration or excision of brain abscess[es]). The advantages and disadvantages of both strategies are summarised. Our opinion is that the use of the 'conservative strategy' should be limited to well-selected patients presenting with an easily accessible extra-neurological lesion(s) and have brain abscesses at low risk of treatment failure. In terms of antimicrobial therapy, we summarise the data supporting the use of a multidrug regimen in patients with brain nocardiosis.Last, we list possible reasons for treatment failure in patients with brain nocardiosis and suggest interventions to overcome them. SUMMARY: Literature is scarce regarding brain nocardiosis, as a consequence of the rarity of this disease. A multidisciplinary and individualised management is required to optimise the outcome of patients with brain nocardiosis.

Long-term use of liposomal nebulized amikacin and tedizolid for the treatment of disseminated nocardiosis after allogeneic hematopoietic stem cell transplantation.

Nocardiosis is a life-threatening opportunistic infection in immunocompromised patients. Herein, we present successful adjunctive use of liposomal nebulized amikacin and tedizolid in a recipient of allogeneic hematopoietic stem cell transplantation infected with Nocardia nova complex who presented multiple complications to conventional therapeutic options.

Mycobacterium bovis infection of an aortobifemoral bypass graft with Streptococcus intermedius superinfection after intravesical bacillus Calmette-Guérin immunotherapy for bladder cancer.

BACKGROUND: The Bacillus Calmette-Guerin (BCG) is a life-attenuated form of Mycobacterium bovis widely used as immunotherapy for localized bladder cancer. Adverse reactions to intravesical BCG instillations are rare. CASE: We describe a 70-year-old man with a history of an aortobifemoral bypass graft, placement of a synthetic mesh for treatment of a ventral hernia and, most recently, superficial bladder cancer treated with BCG therapy. Ten months after his final intravesical BCG instillation, he complained of fever and asthenia. After 12 months of investigation, he was diagnosed with Mycobacterium bovis infection of his aortobifemoral bypass graft and abdominal mesh, with Streptococcus intermedius superinfection. The bypass graft was excised and replaced with an in situ arterial allograft, the abdominal mesh was removed, and treatment started with amoxicillin, isoniazid, rifampicin and ethambutol. Several additional vascular interventions were needed for allograft degradation, but 12 months after the final procedure, outcome was good. DISCUSSION AND CONCLUSIONS: Among 35 cases of mycotic aneurysm reported after BCG therapy in the last 10 years, only one involved a vascular prosthesis. Surgical repair of such aneurysms using prosthetic grafts is commonly performed, associated with anti-mycobacterial treatment. Prognosis is poor with mortality of 14% (4/35) and a 26% rate of aneurysm recurrence under treatment (9/35).

Trimethoprim/sulfamethoxazole for nocardiosis in solid organ transplant recipients: Real-life data from a multicentre retrospective study.

BACKGROUND: Little is known regarding the optimal management of nocardiosis among solid organ transplant (SOT) recipients. It is often suggested to avoid trimethoprim/sulfamethoxazole (TMP-SMX) monotherapy in heavily immunocompromised patients (such as SOT recipients) and/or in case of severe or disseminated nocardiosis. Our aim was to report our experience with TMP-SMX monotherapy in SOT recipients with nocardiosis. METHODS: Using data from a previously published European study, we assessed the incidence of adverse events in SOT recipients receiving TMP-SMX monotherapy and assessed its effectiveness. RESULTS: Thirty-one SOT recipients with nocardiosis were included, mostly kidney transplant recipients (20/31, 65%). Eleven (36%) had disseminated infection, and four (13%) had brain nocardiosis. Most patients had lung and/or pleural involvement (26/31, 84%). Daily dose of trimethoprim at initiation was 10 [6.4-14.8] mg/kg. The median estimated glomerular filtration rate at time of diagnosis of nocardiosis was 44 [30-62] ml/min/1.73 m². TMP-SMX was discontinued prematurely in one third of the patients (10/31, 32%, mostly for hematological toxicity [n = 3] or increased serum creatinine [n = 3]). Focusing on the 24 (77%) patients who completed at least 30 days of TMP-SMX monotherapy, 4 had late (>30 days) drug discontinuation, 1 experienced treatment failure, and 19 completed planned TMP-SMX monotherapy. Clinical outcome was favorable in these 19 patients, despite the fact that 8 (42%) had disseminated infection and 2 (11%) brain nocardiosis. Overall, all-cause 1-year mortality was 10% (3/31). CONCLUSIONS: TMP-SMX monotherapy appears to be effective for the treatment of most nocardiosis among SOT recipients. Interventional studies are needed to compare its safety and effectiveness with those of other regimens used to treat posttransplant nocardiosis.

Assessment of Bacterial Colonization of Intracranial Pressure Transducers: A Prospective Study.

OBJECTIVES: Cerebral infections related to the presence of an intraparenchymal intracranial pressure transducer (ICPT) are rare. We assessed the incidence of ICPT-related infections and colonization using culture, molecular biology, and electron microscopy. METHODS: All consecutive patients in a neurosurgical intensive care unit who had an ICPT inserted between March 2017 and February 2018 were prospectively included. Presence of colonization on the ICPTs was assessed after removal using culture, scanning electron microscopy (SEM), and next-generation sequencing (NGS). RESULTS: Fifty-three ICPTs (53 patients), indwelling for a median of 4 (range 3-7) days, were studied. Median patient follow-up was 3 months. SEM, microbial culture, and NGS were performed for 91%, 79%, and 72% of ICPTs, respectively; 28 ICPTs (53%) were assessed using all three techniques. No patient developed ICPT-related infection. Microbial cultures were positive for two of the ICPTs (5%); colonization was identified on all ICPTs using NGS and SEM. Mature biofilm was observed on 35/48 (73%) of ICPTs. A median of 10 (8-12) operational taxonomic units were identified for each ICPT, most being of environmental origin. There was no association between biofilm maturity and antimicrobial treatment or duration of ICPT insertion. Antimicrobial treatment was associated with decreased alpha and beta-diversity (p = 0.01). CONCLUSIONS: We observed no ICPT-related cerebral infections although colonization was identified on all ICPTs using NGS and SEM. Mature biofilm was the main bacterial lifestyle on the ICPTs.

Inhibition Activity of Avibactam against Nocardia farcinica ß-Lactamase FARIFM10152.

Nocardia farcinica, one of the most frequent pathogenic species responsible for nocardiosis, is characterized by frequent brain involvement and resistance to ß-lactams mediated by a class A ß-lactamase. Kinetic parameters for hydrolysis of various ß-lactams by FARIFM10152 from strain IFM 10152 were determined by spectrophotometry revealing a high catalytic activity (kcat/Km ) for amoxicillin, aztreonam, and nitrocefin. For cephems, kcat/Km was lower but remained greater than 104 M-1 s-1 A low catalytic activity was observed for meropenem, imipenem, and ceftazidime hydrolysis. FARIFM10152 inhibition by avibactam and clavulanate was compared using nitrocefin as a reporter substrate. FARIFM10152 was efficaciously inhibited by avibactam with a carbamoylation rate constant (k2/Ki ) of (1.7 ± 0.3) × 104 M-1 s-1 The 50% effective concentrations (EC50s) of avibactam and clavulanate were 0.060 ± 0.007 µM and 0.28 ± 0.06 µM, respectively. Amoxicillin, cefotaxime, imipenem, and meropenem MICs were measured for ten clinical strains in the presence of avibactam and clavulanate. At 4 µg/ml, avibactam and clavulanate restored amoxicillin susceptibility in all but one of the tested strains but had no effect on the MICs of cefotaxime, imipenem, and meropenem. At 0.4 µg/ml, amoxicillin susceptibility (MIC ≤ 8 µg/ml) was restored for 9 out of 10 strains by avibactam but only for 4 out of 10 strains by clavulanate. Together, these results indicate that avibactam was at least as potent as clavulanate, suggesting that the amoxicillin-avibactam combination could be considered as an option for the rescue treatment of N. farcinica infections if clavulanate cannot be used.

Nocardiosis Associated with Primary Immunodeficiencies (Nocar-DIP): an International Retrospective Study and Literature Review.

PURPOSE: Nocardiosis is a life-threatening infectious disease. We aimed at describing nocardiosis in patients with primary immunodeficiency diseases (PID). METHODS: This international retrospective cohort included patients with PID and nocardiosis diagnosed and/or published from Jan 1, 2000, to Dec 31, 2016. To identify nocardiosis cases, we analyzed PID databases from the French National Reference Center for PID (Paris, France) and the National Institute of Health (NIH, United States of America) and we performed a literature review on PubMed. RESULTS: Forty-nine cases of nocardiosis associated with PID were included: median age at diagnosis of nocardiosis was 19 (0-56) years and most cases were observed among chronic granulomatous disease (CGD) patients (87.8%). Median time from symptoms to diagnosis of Nocardia infection was 20 (2-257) days. Most frequent clinical nocardiosis presentation was pneumonia (86.7%). Twelve-month mortality rate was 4.2%, and 11.9% of patients experienced a possible recurrence of infection. Nocardiosis more frequently led to the diagnosis of PID among non-CGD patients than in CGD patients. Non-CGD patients experienced more cerebral nocardiosis and more disseminated infections, but mortality and recurrence rates were similar. Highest incidences of nocardiosis among PID cohorts were observed among CGD patients (0.0057 and 0.0044 cases/patient-year in the USA and in France, respectively), followed by IL-12p40 deficiency. CONCLUSIONS: Among 49 cases of nocardiosis associated with PID, most patients had CGD and lung involvement. Both mortality and recurrence rates were low.

Impact of panelists' experience on script concordance test scores of medical students.

BACKGROUND: The evaluation process of French medical students will evolve in the next few years in order to improve assessment validity. Script concordance testing (SCT) offers the possibility to assess medical knowledge alongside clinical reasoning under conditions of uncertainty. In this study, we aimed at comparing the SCT scores of a large cohort of undergraduate medical students, according to the experience level of the reference panel. METHODS: In 2019, the authors developed a 30-item SCT and sent it to experts with varying levels of experience. Data analysis included score comparisons with paired Wilcoxon rank sum tests and concordance analysis with Bland & Altman plots. RESULTS: A panel of 75 experts was divided into three groups: 31 residents, 21 non-experienced physicians (NEP) and 23 experienced physicians (EP). Among each group, random samples of N = 20, 15 and 10 were selected. A total of 985 students from nine different medical schools participated in the SCT examination. No matter the size of the panel (N = 20, 15 or 10), students' SCT scores were lower with the NEP group when compared to the resident panel (median score 67.1 vs 69.1, p < 0.0001 if N = 20; 67.2 vs 70.1, p < 0.0001 if N = 15 and 67.7 vs 68.4, p < 0.0001 if N = 10) and with EP compared to NEP (65.4 vs 67.1, p < 0.0001 if N = 20; 66.0 vs 67.2, p < 0.0001 if N = 15 and 62.5 vs 67.7, p < 0.0001 if N = 10). Bland & Altman plots showed good concordances between students' SCT scores, whatever the experience level of the expert panel. CONCLUSIONS: Even though student SCT scores differed statistically according to the expert panels, these differences were rather weak. These results open the possibility of including less-experienced experts in panels for the evaluation of medical students.