Real-world evaluation of linezolid-associated serotonin toxicity with and without concurrent serotonergic agents.

BACKGROUND: The risk of linezolid-associated serotonin toxicity remains unclear. This study sought to evaluate the incidence of serotonin toxicity among hospitalized patients who received linezolid with or without concurrent serotonergic agents (SAs). Secondary outcomes were to assess the dose, agent selection and number of SAs. METHODS: A single-centre, retrospective cohort study of hospitalized patients aged ≥18 years who received at least one dose of linezolid with or without SAs between 1 January 2014 and 30 June 2021 was performed. Patients were excluded if they were aged <18 years, had linezolid ordered but not administered, were pregnant or were incarcerated. Up to five concurrent SAs were assessed, and dose category was classed as low, moderate or high (dose <33%, 33-66% or >66% of maximum daily dose, respectively). Serotonin toxicity was identified by searching patients' electronic medical records. If identified, the Sternbach criteria and Hunter criteria were applied. RESULTS: Of 2022 patients screened, 1743 were included in this study. Mean age, weight and linezolid duration were 58.5 years, 90.7 kg and 3.8 days, respectively. Approximately 67% (1168/1743) of patients received linezolid with at least one SA, and several patients received multiple SAs. Most patients (53.8%; 616/1144) received moderate- and/or high-dose SAs. Only two patients (0.11%) were identified as possible cases of serotonin toxicity based on the electronic medical record search. However, the incidence of serotonin toxicity was 0.06% (1/1743) based on the Sternbach criteria and 0% (0/1743) based on the Hunter criteria. CONCLUSIONS: Serotonin toxicity among hospitalized patients who received linezolid with or without SAs was exceedingly rare, even among those who received multiple and high-dose SAs.

Vancomycin plus ceftaroline for persistent methicillin-resistant Staphylococcus aureus bacteremia.

STUDY OBJECTIVE: The preferred antibiotic salvage regimen for persistent methicillin-resistant Staphylococcus aureus bacteremia (MRSAB) is unclear. We sought to evaluate the effectiveness and safety of vancomycin plus ceftaroline for persistent MRSAB. The primary outcome was time to MRSAB clearance post-ceftaroline initiation. Secondary outcomes included microbiological cure, hospital length of stay, 90-day readmission for MRSAB, 90-day all-cause mortality, MRSAB-related mortality, and incidence of antibiotic-associated adverse effects. DESIGN: Single-center, retrospective cohort study between January 1, 2016, and December 31, 2021. SETTING: State University of New York Upstate University Hospital, a 748-bed tertiary care, academic medical center in Syracuse, NY. PATIENTS: Adult patients were included if they had blood cultures positive for MRSA ≥72 h, received vancomycin monotherapy initially, and received vancomycin plus ceftaroline for ≥24 h. Patients were excluded if they received other anti-MRSA antibiotics, were pregnant, or were incarcerated. Of the 178 patients identified, 30 unique patients were evaluated. MEASUREMENTS AND MAIN RESULTS: Patients were medically complex with a median Pitt bacteremia score of 3, 63.3% (19/30) were admitted to the intensive care unit, and 66.7% (20/30) had infective endocarditis. Vancomycin-associated acute kidney injury was observed in 10% (3/30) of patients, which resulted in dose adjustments. No patients experienced ceftaroline-associated neutropenia or Clostridioides difficile infection, but 6.7% (2/30) developed a rash attributed to ceftaroline. Median time to MRSAB clearance post-ceftaroline initiation was 2.6 days. Microbiologic cure occurred in nearly all patients 96.7% (29/30). Median hospital length of stay was 19.5 days, and 6.7% (2/30) of patients had 90-day readmission for MRSAB. 90-day all-cause mortality and MRSAB-related mortality occurred in 26.7% (8/30) and 13.3% (4/30) of patients, respectively. CONCLUSIONS: Vancomycin plus ceftaroline may represent an effective and well-tolerated salvage regimen option for persistent MRSAB.

Evaluation of ß-lactam therapeutic drug monitoring among US health systems with postgraduate year 2 infectious diseases pharmacy residency programs.

PURPOSE: While some guidelines recognize the need for ß-lactam therapeutic drug monitoring (TDM), there is still a paucity of data regarding the prevalence of and barriers to performing ß-lactam TDM in the United States. We sought to estimate the prevalence of ß-lactam TDM, describe monitoring practices, and identify actual and perceived barriers to implementation among health systems in the US. METHODS: A multicenter, cross-sectional, 40-item electronic survey was distributed to all postgraduate year 2 (PGY2) infectious diseases (ID) pharmacy residency program directors (RPDs) listed in the American Society of Health-System Pharmacists pharmacy residency directory. The primary outcome was the percentage of institutions with established ß-lactam TDM. Secondary outcomes included assessing ß-lactam TDM methods and identifying potential barriers to implementation. RESULTS: The survey was distributed to 126 PGY2 ID RPDs, with a response rate of 31.7% (40 of 126). Only 8% of respondents (3 of 39) performed ß-lactam TDM. Patient populations, therapeutic targets, and frequency and timing of obtaining repeat ß-lactam concentration measurements varied among institutions. The greatest barrier to implementation was lack of access to testing with a rapid turnaround time. Institutions were unlikely to implement ß-lactam TDM within the next year but were significantly more inclined to do so within 5 years (P < 0.001). CONCLUSION: ß-lactam TDM was infrequently performed at the surveyed US health systems. Lack of access to serum concentration testing with rapid turnaround and lack of US-specific guidelines appear to be considerable barriers to implementing ß-lactam TDM. Among institutions that have implemented ß-lactam TDM, there is considerable variation in monitoring approaches.

Andexanet alfa effectiveness and safety versus four-factor prothrombin complex concentrate (4F-PCC) in intracranial hemorrhage while on apixaban or rivaroxaban: A single-center, retrospective, matched cohort analysis.

BACKGROUND: There is limited information directly comparing andexanet alfa (AA) versus four-factor prothrombin complex concentrate (4F-PCC) in intracranial hemorrhage (ICH) on apixaban or rivaroxaban. OBJECTIVE: The objective of this study was to compare the effectiveness and safety of AA versus 4F-PCC in ICH on apixaban or rivaroxaban. METHODS: This retrospective, matched, cohort analysis was conducted at a single healthcare system. Patients were matched based on baseline ICH volume. The primary outcome was good or excellent ICH hemostasis, which was defined as a 35% or less increase in ICH volume within 24 h following AA or 4F-PCC administration. The secondary outcome was thrombotic events within 14 days following AA or 4F-PCC administration. RESULTS: In total, 26 AA and 26 4F-PCC patients were included in this matched cohort analysis. Both groups had comparable rates of good or excellent ICH hemostasis (AA: 92.3% vs. 4F-PCC: 88.5%, p = 1.000). Thrombotic events within 14-days were not significantly different (AA: 26.9% vs. 4F-PCC: 11.5%, p = 0.159). CONCLUSION AND RELEVANCE: This study found no significant differences in good or excellent ICH hemostasis within 24-h or new thrombotic events within 14-days in a cohort given AA or 4F-PCC for ICH while on apixaban or rivaroxaban. However, this single-center analysis is underpowered due to sample size constraints, therefore further high-quality research comparing AA safety and effectiveness versus 4F-PCC is needed.

Hospital Discharge: An Opportune Time for Antimicrobial Stewardship.

BACKGROUND: Approximately 30% of antimicrobials prescribed in the outpatient setting are unnecessary and up to 50% are inappropriate. Despite this, antimicrobial stewardship (AS) efforts mostly focus on the inpatient setting, and limited data describe AS interventions at hospital discharge. Acknowledging the potential value of discharge AS, we used our existing resources to review discharge oral antimicrobial prescriptions. OBJECTIVE: The primary objective of this retrospective, single-center study was to evaluate the impact of an AS program on discharge oral antimicrobial prescriptions. METHODS: Discharge oral antimicrobial prescriptions sent to our hospital-operated outpatient pharmacy, reviewed by an infectious diseases (ID) pharmacist, and recorded into our data collection tool from September 1, 2020, to February 28, 2021, were evaluated retrospectively. The primary outcome was to identify the frequency a drug-related problem (DRP) was identified by an ID pharmacist. Secondary outcomes included DRP characterization, percentage of prescriptions with interventions, intervention acceptance rate, and reduction in antimicrobial days dispensed at discharge when interventions to limit treatment duration were accepted. RESULTS: Of the 803 discharge oral antimicrobial prescriptions reviewed, at least 1 DRP was identified in 43.1% (346/803). The most frequently identified DRPs pertained to treatment duration, drug selection, and dose selection. At least 1 intervention was recommended in 42.8% (344/803) of prescriptions. In total, 438 interventions were made and the acceptance rate was 75.6% (331/438). The most common types of interventions included recommendations for a different duration, a different dose or frequency, and antimicrobial discontinuation. When interventions to reduce treatment duration were accepted, the median (interquartile range) number of antimicrobial days decreased from 8 (5-10) days to 4 (0-5.5) days (P < 0.001). CONCLUSION AND RELEVANCE: An ID pharmacist's review of discharge oral antimicrobial prescriptions sent to our hospital-operated outpatient pharmacy resulted in identification of DRPs and subsequent interventions in a substantial number of prescriptions.

Successful treatment with secnidazole for trichomoniasis in the setting of metronidazole hypersensitivity.

Limited effective treatment options currently exist for trichomoniasis management among patients with metronidazole hypersensitivity. We report a patient with a documented history of metronidazole hypersensitivity who initially was treated with nitazoxanide but demonstrated clinical and microbiological failure. Secnidazole was subsequently used for treatment, which resulted in clinical and microbiological cure without observation of cross-reactivity. Secnidazole may represent a potential treatment option for trichomoniasis in patients with metronidazole hypersensitivity after consultation with an infectious disease specialist.

Cefiderocol: a novel siderophore cephalosporin for multidrug-resistant Gram-negative bacterial infections.

Cefiderocol is a novel siderophore cephalosporin that forms a complex with extracellular free ferric iron, which leads to transportation across the outer cell membrane to exert its bactericidal activity through cell wall synthesis inhibition. This pharmacological property has rendered cefiderocol active against several clinically relevant MDR Gram-negative bacteria as evidenced by several in vitro and in vivo studies. Cefiderocol was first approved by the US FDA on 14 November 2019 for the treatment of complicated urinary tract infections. On 28 September 2020, cefiderocol was approved for the treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia. The FDA-approved indications are based on clinical data from the APEKS-cUTI, APEKS-NP and CREDIBLE-CR trials. In APEKS-cUTI, cefiderocol demonstrated non-inferiority to imipenem/cilastatin for the treatment of complicated urinary tract infection caused by MDR Gram-negative bacteria. In APEKS-NP, cefiderocol demonstrated non-inferiority to meropenem for treatment of nosocomial pneumonia. However, in CREDIBLE-CR, higher all-cause mortality was observed with cefiderocol compared with best available therapy for the treatment of severe infections caused by Gram-negative bacteria, primarily in the subset of patients with Acinetobacter spp. infections. Several case reports/series have demonstrated clinical success with cefiderocol for a variety of severe infections. The purpose of this article is to review available data on the mechanism of action, in vitro and in vivo data, pharmacokinetics, pharmacodynamics, susceptibility testing, efficacy and safety of cefiderocol to address its role in therapy.