Journal of Antimicrobial Chemotherapy最新文献

Objectives: Bioengineered artificial skin substitutes (BASS) are an advanced therapy for treating extensively burned patients. Pseudomonas aeruginosa (P. aeruginosa) infections represent a major challenge in these patients as formation of biofilms impede wound healing and perpetuate a chronic inflammatory state. Here we assessed antibiotics (alone or in combination) with respect to cytotoxicity, as well as antimicrobial efficacy in P. aeruginosa biofilm formed on infection of BASS.

Methods: Cell viability, structure and functionality were evaluated using microscopy and trans-epidermal water loss analyses, respectively. BASS were established and infected for 24 h to allow P. aeruginosa biofilm formation, after which two antimicrobial approaches, treatment and prevention, were tested. In the latter, antibiotics were added to BASS before infection. The antimicrobial effect was determined using real-time calorimetry.

Results: In dose-response experiments, 1.25 mg/mL amikacin, 0.02 mg/mL ciprofloxacin, 0.051 mg/mL colistin, 1 mg/mL meropenem and colistin in combination with either amikacin, ciprofloxacin and meropenem did not affect BASS' viability, structure and functionality. All antibiotics, except colistin, showed effective antimicrobial activity at these non-cytotoxic concentrations. For concentrations below the highest non-cytotoxic ones, successive treatments resulted in higher bacterial metabolic rates. Only the combinations managed to eradicate the infection with repeated treatments. With respect to prevention of infection, all antibiotics at the highest non-cytotoxic concentrations and the combinations were effective. This preventive capacity was maintained for at least 5 days.

Conclusion: The findings highlight the potential for developing BASS with antimicrobial properties that can prevent infections during wound healing in burn patients.

Background: Uncertainty exists as to the role of fluoroquinolone (FQ) prophylaxis for patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT) in the era of rising antibiotic resistance.

Objectives: We aimed to evaluate rates of bloodstream infections (BSI), resistance patterns and outcomes of patients after discontinuing routine FQ prophylaxis administration.

Methods: All adult recipients of first HSCT from 2017 to 2020 were retrospectively included and classified according to time of HSCT as FQ group (HSCT January 2017-December 2018) or no FQ group (January 2019-December 2020). The primary outcome was Gram-negative (GN) BSI from day -7 to 30 days post-HSCT. The independent association between the study period and BSI was assessed using survival analysis, and adjusting for confounders.

Results: We included 254 patients, 130 (51%) and 124 (49%) in the FQ and no FQ groups, respectively. Compared to the FQ group, no FQ had significantly more GN BSI (21% versus 33%, P = 0.027) and the median time to first GN BSI was significantly shorter [4 (IQR 1-8) days versus 6 (1-10) days, P = 0.009]. Following adjustment, FQ prophylaxis remained associated with lower hazard for GN BSI (hazard ratio 0.57, 95% CI 0.34-0.93). Eighty-two GN BSI episodes had FQ susceptibility testing. More GN BSI episodes were FQ resistant in the FQ group (68.9% versus 41.6%, P = 0.021). No significant difference was found for 30-day mortality, time to first febrile neutropenia and time to first broad-spectrum antibiotics between the groups (P was not significant).

Conclusions: FQ prophylaxis is associated with fewer GN BSI in the early post-HSCT period even in high FQ resistance settings, with FQ resistance rates reaching >60% following prophylaxis.

Background: Resistance to carbapenems, the first-line treatment for infections caused by Acinetobacter baumannii, is increasing throughout the world. The aim of the present study was to determine the global status of resistance to carbapenems in clinical isolates of this pathogen, worldwide.

Methods: Electronic databases were searched using the appropriate keywords, including: 'Acinetobacter' 'baumannii', 'Acinetobacter baumannii' and 'A. baumannii', 'resistance', 'antibiotic resistance', 'antibiotic susceptibility', 'antimicrobial resistance', 'antimicrobial susceptibility', 'carbapenem', 'carbapenems', 'imipenem', 'meropenem' and 'doripenem'. Finally, following some exclusions, 177 studies from various countries were included in this study. The data were then subjected to a meta-analysis.

Results: The average resistance rate of A. baumannii to imipenem, meropenem and doripenem was 44.7%, 59.4% and 72.7%, respectively. A high level of heterogeneity (I2 > 50%, P value < 0.05) was detected in the studies representing resistance to imipenem, meropenem and doripenem in A. baumannii isolates. Begg's and Egger's tests did not indicate publication bias (P value > 0.05).

Conclusions: The findings of the current study indicate that the overall resistance to carbapenems in clinical isolates of A. baumannii is relatively high and prevalent throughout the world. Moreover, time trend analysis showed that the resistance has increased from the year 2000 to 2023. This emphasizes the importance of conducting routine antimicrobial susceptibility testing before selecting a course of treatment, as well as monitoring and controlling antibiotic resistance patterns in A. baumannii strains, and seeking novel treatment options to lessen the emergence and spread of resistant strains and to reduce the treatment failure.

Background: The management of acute prosthetic joint infections (PJIs) often involves a debridement, antibiotics and implant retention (DAIR) strategy.

Objective: Our objective was to conduct a systematic review and a network meta-analysis (NMA) to assess the comparative effectiveness of available oral antimicrobial regimens for the treatment of acute staphylococcal PJIs treated with DAIR.

Methods: We conducted a systematic review searching articles from databases creation until 31 December 2023. We included articles on acute staphylococcal PJIs managed with DAIR with an oral antibiotic regimen relaying the initial management. The primary outcome was the remission rate.

Results: Out of the 2421 studies screened, six studies completed the systematic review criteria: one randomized controlled trial and five observational studies. There was heterogeneity in patients' populations, duration and posology of treatments, definition of outcome and length of follow-up. Studies revealed 10 antibiotic regimens and most data focusing on five combinations recommended by the IDSA's guidelines: rifampicin associated to fluoroquinolone, clindamycin, cycline, linezolid or trimethoprim-sulfamethoxazole. Treatment comparisons were often secondary, without adjustment for confounding factors, resulting in a high risk of bias. Owing to inconsistencies a complete analysis, including an NMA was not possible.

Conclusion: The available data highlight five companions to rifampicin, however, there is insufficient evidence to compare them. The literature does not provide a basis for rationalizing alternatives when rifampicin cannot be used.

Objectives: To review the evidence on healthcare professionals' (HCPs) and patients' views of the use of point-of-care tests (POCTs) in the management of acute respiratory tract infections (RTIs) in primary care settings.

Methods: We conducted a systematic review of studies up to 28 April 2023. We included studies that included qualitative methods and results; focused on HCPs' and/or patients' views/experiences of POCTs for acute RTIs; and were conducted in primary care settings. We conducted a thematic synthesis to identify how their views on POCTs and interventions can support test use (PROSPERO registration: CRD42019150347).

Results: We included 33 studies, developing 9 categories each for HCP and patient data. We identified 38 factors affecting POCT use: 28 from HCPs and 10 from patients. Factors exist outside and within consultations, and post-consultations, illustrating that some cannot be addressed by HCPs alone. Fourteen interventions were identified that could address factors and support POCT use, with 7 interventions appearing to address the most factors. Some interventions were beyond the scope of HCPs and patients and needed to be addressed at system and organizational levels. Both groups had mixed views on the use of POCTs and highlighted implementation challenges.

Discussion: This review highlights numerous factors affecting POCT use in primary care. Policy-makers planning to implement POCTs are likely to achieve more by providing multi-faceted interventions that target factors outside, within, and post-consultation. Some interventions may need to be already established before POCT introduction. Whilst evidence beyond general practice is limited, similar factors suggest that similar context-tailored interventions would be appropriate.

Objectives: Clofazimine is a promising drug for the treatment of nontuberculous mycobacterial (NTM) diseases. Accumulation of clofazimine to reach steady-state plasma concentrations takes months. A loading dose may reduce the time to steady-state-like concentrations. We evaluated the pharmacokinetics (PK), safety and tolerability of a loading dose regimen in patients with NTM disease.

Methods: Adult participants received a 4-week loading dose regimen of 300 mg clofazimine once daily, followed by a maintenance dose of 100 mg once daily (combined with other antimycobacterial drugs). Blood samples for PK analysis were collected on three occasions. A population PK model for clofazimine was developed and simulations were performed to assess the time to reach steady-state-like (target) concentrations for different dosing regimens.

Results: Twelve participants were included. The geometric mean peak and trough clofazimine concentrations after the 4-week loading phase were 0.87 and 0.50 mg/L, respectively. Adverse events were common, but mostly mild and none led to discontinuation of clofazimine. Our loading dose regimen reduced the predicted median time to target concentrations by 1.5 months compared to no loading dose (3.8 versus 5.3 months). Further time benefit was predicted with a 6-week loading dose regimen (1.4 versus 5.3 months).

Conclusion: A 4-week loading dose regimen of 300 mg once daily reduced the time to target clofazimine concentrations and was safe and well-tolerated. Extending the loading phase to 6 weeks could further decrease the time to target concentrations. Using a loading dose of clofazimine is a feasible strategy to optimize treatment of NTM disease.

Clinical trials registration: NCT05294146.

Background: The rise in carbapenem-resistant bacteria and the limited number of effective antibiotics pose a major health-care threat. The combination of ceftazidime (CAZ) and avibactam (AVI) represents an approved treatment option for carbapenem-resistant intra-abdominal infections. However, data on the pharmacokinetic profile of AVI in the hepatobiliary compartment is lacking.

Objectives: To provide clinical in vivo data on the concentration of AVI in bile fluid as a surrogate for hepatobiliary excretion.

Methods: A single dose of 2000/500 mg CAZ/AVI was administered prolonged over 2 h to 10 patients prior to abdominal surgery, with bile samples available in nine patients in this phase IIb study (DRKS-ID: DRKS00023533). Antibiotic concentrations in plasma (0-8 h), bile (after resection) and pharmacodynamic parameters were determined.

Results: The mean concentration across individuals in bile was 33.5 mg/L (±20.5 mg/L) for CAZ and 7.1 mg/L (±3.5 mg/L) for AVI, resulting in bile/plasma ratios of 0.58 (±0.26) and 0.61 (±0.18). The Cmax in plasma was 87.2 mg/L (±25.0 mg/L) for CAZ and 18.6 mg/L (±6.29 mg/L) for AVI, with AUC0-∞ values of 351 h·mg/L (±104 h·mg/L) and 72.1 h·mg/L (±32.1 h·mg/L), respectively. Plasma concentrations of both CAZ and AVI remained more than 50% of the dosing interval above the minimum inhibitory concentrations (T>MIC > 50%; MICCAZ = 8 mg/L, MICAVI = 1 mg/L) in all patients. No antibiotic-associated side effects were reported during the 30-day follow-up.

Conclusions: The concentrations of CAZ and AVI in bile suggest their potential as a valuable therapeutic option for multi-resistant biliary infections.

Background: The effectiveness of the early treatment for antiviral agents in SARS-CoV-2 infection is closely related to patient comorbidities. Data on effectiveness in immunocompromised patients are limited, with reports involving highly heterogeneous and not well-defined populations. We aimed to assess the effectiveness of treatment in reducing hospitalizations in a real-world cohort of severely immunocompromised COVID-19 outpatients.

Patients and methods: We conducted a multicentre, retrospective, observational cohort study of immunocompromised outpatients attended in infectious diseases departments from 1 January to 31 December 2022. Propensity score matching (PSM) multivariable logistic regression models were used to estimate the adjusted odds ratio [(aOR, 95% confidence interval (CI)] for the association between antiviral prescription and outcome (COVID-19-related hospitalization up to Day 90).

Results: We identified 746 immunocompromised outpatients with confirmed SARS-CoV-2 infection. After eligibility criteria and PSM, a total of 410 patients were analysed: 205 receiving treatment (remdesivir, sotrovimab or nirmatrelvir/ritonavir) and 205 matched controls. Fifty-two patients required at least one COVID-19-related hospitalization 8 (3.9%) versus 44 (21.5%) in the antiviral and matched control cohorts, respectively. There were 13 deaths at 90 days, of which only 4 were COVID-19-related and none in the antiviral treatment group. After adjustment for residual confounders, the use of early therapy was associated with a protective effect on the risk of hospitalization [aOR 0.13 (0.05-0.29)], as was the use of biological immunomodulators [aOR 0.27 (0.10-0.74)], whereas chronic obstructive pulmonary disease [aOR 4.65 (1.09-19.69)] and anti-CD20 use [aOR 2.76 (1.31-5.81)] increased the odds.

Conclusions: Early antiviral treatment was associated with a reduced risk of COVID-19-related hospitalization in ambulatory severely immunocompromised COVID-19 patients.