Exploration of Daptomycin Adsorption by Polymethylmethacrylate Hemofilter In Vitro.

Blood purification therapy with cytokine-adsorbing hemofilters has been used to treat sepsis-associated hypercytokinemia. Polymethylmethacrylate (PMMA) hemofilters are frequently used for this purpose; however, adsorption and removal of teicoplanin, a therapeutic agent, have been reported. Similar concerns have been shared regarding daptomycin because its structure resembles that of teicoplanin; nevertheless, there have been no reported effects associated with daptomycin in this context. We studied the adsorption of daptomycin onto a PMMA hemofilter in vitro and investigated its adsorption onto hollow fiber membranes by adding cut PMMA membranes to a daptomycin solution. Additionally, the daptomycin solution was circulated in a dialysis circuit connected to a PMMA hemofilter, and changes in daptomycin content were examined. The daptomycin content decreased immediately after adding the hollow fiber membranes, similar to that observed for teicoplanin. The daptomycin content was lower than that of the standard reagent in the dialysis circuit model, reaching values below the measurement limit after 20 min. These results suggested that daptomycin was adsorbed and removed by the PMMA hemofilter. Encountering this effect during clinical use is plausible; therefore, daptomycin administration via a PMMA hemofilter should be avoided during blood purification therapy.

Assessing the stability of daptomycin in icodextrin-based peritoneal dialysis solution.

BACKGROUND: The stability of antimicrobials in peritonitis during peritoneal dialysis (PD) solutions is a critical factor influencing treatment success. This study investigated the stability of daptomycin (DAP) when combined with icodextrin-based PD solution, by measuring DAP concentrations and observing any structural changes. METHODS: A dose of DAP (350 mg) was dissolved in 7 mL of saline in a clean bench. The solution was then injected into the large compartment (1,260 mL) of NICOPELIQ® Peritoneal Dialysis Solution and thoroughly mixed. Samples were collected at intervals ranging from 0 to 336 h (7 points in total). The concentration of DAP was quantified using high-performance liquid chromatography (HPLC). The structure of any unidentified peaks was determined using HPLC coupled with electrospray ionization tandem mass spectrometry. RESULTS: DAP maintained 90% of the initial concentration in NICOPELIC® for 72 h at room temperature and 12 h at 37 °C. Unidentified peaks, distinct from DAP, were detected during analysis. Further investigation indicated that these peaks corresponded to anhydrated DAP. CONCLUSIONS: The findings from this stability study are expected to enhance the effectiveness of outpatient management and preparation for treating peritonitis using DAP.

Sentinel Surveillance reveals phylogenetic diversity and detection of linear plasmids harboring vanA and optrA among enterococci collected in the United States.

Enterococcus faecalis and Enterococcus faecium are frequent causes of healthcare-associated infections. Antimicrobial-resistant enterococci pose a serious public health threat, particularly vancomycin-resistant enterococci (VRE), for which treatment options are limited. The Centers for Disease Control and Prevention's Division of Healthcare Quality Promotion Sentinel Surveillance system conducted surveillance from 2018 to 2019 to evaluate antimicrobial susceptibility profiles and molecular epidemiology of 205 E. faecalis and 180 E. faecium clinical isolates collected from nine geographically diverse sites in the United States. Whole genome sequencing revealed diverse genetic lineages, with no single sequence type accounting for more than 15% of E. faecalis or E. faecium. Phylogenetic analysis distinguished E. faecium from 19 E. lactis (previously known as E. faecium clade B). Resistance to vancomycin was 78.3% among E. faecium, 7.8% among E. faecalis, and did not occur among E. lactis isolates. Resistance to daptomycin and linezolid was rare: E. faecium (5.6%, 0.6%, respectively), E. faecalis (2%, 2%), and E. lactis (5.3%, 0%). All VRE harbored the vanA gene. Three of the seven isolates that were not susceptible to linezolid harbored optrA, one chromosomally located and two on linear plasmids that shared a conserved backbone with other multidrug-resistant conjugative linear plasmids. One of these isolates contained optrA and vanA co-localized on the linear plasmid. By screening all enterococci, 20% of E. faecium were predicted to harbor linear plasmids, whereas none were predicted among E. faecalis or E. lactis. Continued surveillance is needed to assess the future emergence and spread of antimicrobial resistance by linear plasmids and other mechanisms.IMPORTANCEThis work confirms prior reports of E. faecium showing higher levels of resistance to more antibiotics than E. faecalis and identifies that diverse sequence types are contributing to enterococcal infections in the United States. All VRE harbored the vanA gene. We present the first report of the linezolid resistance gene optrA on linear plasmids in the United States, one of which co-carried a vanA cassette. Additional studies integrating epidemiological, antimicrobial susceptibility, and genomic methods to characterize mechanisms of resistance, including the role of linear plasmids, will be critical to understanding the changing landscape of enterococci in the United States.

PBP4 is required for serum-induced cell wall thickening and antibiotic tolerance in Staphylococcus aureus.

The bacterial pathogen Staphylococcus aureus responds to the host environment by synthesizing a thick peptidoglycan cell wall, which protects the bacterium from membrane-targeting antimicrobials and the immune response. However, the proteins required for this response were previously unknown. Here, we demonstrate by three independent approaches that the penicillin-binding protein PBP4 is crucial for serum-induced cell wall thickening. First, mutants lacking various non-essential cell wall synthesis enzymes were tested, revealing that a mutant lacking pbp4 was unable to generate a thick cell wall in serum. This resulted in reduced serum-induced tolerance of the pbp4 mutant toward the last resort antibiotic daptomycin relative to wild-type cells. Second, we found that serum-induced cell wall thickening occurred in each of a panel of 134 clinical bacteremia isolates, except for one strain with a naturally occurring mutation that results in an S140R substitution in the active site of PBP4. Finally, inhibition of PBP4 with cefoxitin prevented serum-induced cell wall thickening and the resulting antibiotic tolerance in the USA300 strain and clinical MRSA isolates. Together, this provides a rationale for combining daptomycin with cefoxitin, a PBP4 inhibitor, to potentially improve treatment outcomes for patients with invasive MRSA infections.

Real-World Clinical Characteristics and Outcomes with Daptomycin Use in Pediatric Patients: A Retrospective Case Series.

INTRODUCTION: Daptomycin (DAP) is a cyclic lipopeptide that exhibits potent in vitro activity against many drug-resistant gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Despite substantial reports evaluating the clinical outcomes of DAP within the adult population, real-world data are lacking in children. The primary goal of this evaluation was to describe the clinical characteristics and outcomes of DAP use in pediatric patients across a wide range of infections. METHODS: This retrospective evaluation included patients < 18 years of age who were treated with DAP from January 2014 to May 2023. The primary objective was to evaluate the composite clinical success, which was defined as a 30-day survival, the lack of a 30-day microbiological recurrence, and the resolution of signs and symptoms of an acute infection without therapy modifications based on clinical failures. Secondary objectives included adverse effects potentially attributable to DAP and reasons for DAP utilization. RESULTS: Forty patients were included, which were predominately male (62.5%) and white (52.5%), with a median age of 8.7 [IQR, 4.4-16.0] years. DAP was used for a wide range of infections, including central line-associated bloodstream infections (CLABSIs; 32.5%), infective endocarditis (15.0%), surgical-site infections (12.5%), and osteomyelitis (12.5%). The most common pathogen isolated was MRSA (37.5%), and most patients were bacteremic (60.0%). The median DAP dose was 8 [IQR, 6-10] mg/kg, and the median duration of the DAP therapy was 11.5 [IQR, 4.8-18.8] days. Most patients achieved composite clinical success (75.0%). An adverse effect occurred in 5.0% of the patients. DAP was prescribed the most for its ease of use/ability to facilitate discharge (40.0%) and/or for issues with alternative therapies (37.5%). CONCLUSION: Most pediatric patients that received DAP demonstrated clinical success with a low incidence of adverse effects. Larger, real-world studies of DAP use are necessary to further assess clinical outcomes.

Overexpression of diglucosyldiacylglycerol synthase leads to daptomycin resistance in Bacillus subtilis.

The lipopeptide antibiotic daptomycin exhibits bactericidal activity against Gram-positive bacteria by forming a complex with phosphatidylglycerol (PG) and lipid II in the cell membrane, causing membrane perforation. With the emergence of daptomycin-resistant bacteria, understanding the mechanisms of bacterial resistance to daptomycin has gained great importance. In this study, we aimed to identify the genetic factors contributing to daptomycin resistance in Bacillus subtilis, a model Gram-positive bacterium. Our findings demonstrated that overexpression of ugtP, which encodes diglucosyldiacylglycerol synthase, induces daptomycin resistance in B. subtilis. Specifically, overexpression of ugtP resulted in increased levels of diglucosyldiacylglycerol (Glc2DAG) and decreased levels of acidic phospholipids cardiolipin and PG, as well as the basic phospholipid lysylphosphatidylglycerol. However, ugtP overexpression did not alter the cell surface charge and the susceptibility to the cationic antimicrobial peptide nisin or the cationic surfactant hexadecyltrimethylammonium bromide. Furthermore, by serial passaging in the presence of daptomycin, we obtained daptomycin-resistant mutants carrying ugtP mutations. These mutants showed increased levels of Glc2DAG and a >4-fold increase in the minimum inhibitory concentration of daptomycin. These results suggest that increased Glc2DAG levels, driven by ugtP overexpression, modify the phospholipid composition and confer daptomycin resistance in B. subtilis without altering the cell surface charge of the bacteria.IMPORTANCEDaptomycin is one of the last-resort drugs for the treatment of methicillin-resistant Staphylococcus aureus infections, and the emergence of daptomycin-resistant bacteria has become a major concern. Understanding the mechanism of daptomycin resistance is important for establishing clinical countermeasures against daptomycin-resistant bacteria. In the present study, we found that overexpression of ugtP, which encodes diglucosyldiacylglycerol synthase, induces daptomycin resistance in B. subtilis, a model Gram-positive bacteria. The overexpression of UgtP increased diglucosyldiacylglycerol levels, resulting in altered phospholipid composition and daptomycin resistance. These findings are important for establishing clinical strategies against daptomycin-resistant bacteria, including their detection and management.

Unraveling novel mutation patterns and morphological variations in two dalbavancin-resistant MRSA strains in Austria using whole genome sequencing and transmission electron microscopy.

BACKGROUND: The increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) strains resistant to non-beta-lactam antimicrobials poses a significant challenge in treating severe MRSA bloodstream infections. This study explores resistance development and mechanisms in MRSA isolates, especially after the first dalbavancin-resistant MRSA strain in our hospital in 2016. METHODS: This study investigated 55 MRSA bloodstream isolates (02/2015-02/2021) from the University Hospital of the Medical University of Vienna, Austria. The MICs of dalbavancin, linezolid, and daptomycin were assessed. Two isolates (16-33 and 19-362) resistant to dalbavancin were analyzed via whole-genome sequencing, with morphology evaluated using transmission electron microscopy (TEM). RESULTS: S.aureus BSI strain 19-362 had two novel missense mutations (p.I515M and p.A606D) in the pbp2 gene. Isolate 16-33 had a 534 bp deletion in the DHH domain of GdpP and a SNV in pbp2 (p.G146R). Both strains had mutations in the rpoB gene, but at different positions. TEM revealed significantly thicker cell walls in 16-33 (p < 0.05) compared to 19-362 and dalbavancin-susceptible strains. None of the MRSA isolates showed resistance to linezolid or daptomycin. CONCLUSION: In light of increasing vancomycin resistance reports, continuous surveillance is essential to comprehend the molecular mechanisms of resistance in alternative MRSA treatment options. In this work, two novel missense mutations (p.I515M and p.A606D) in the pbp2 gene were newly identified as possible causes of dalbavancin resistance.

Intraperitoneal daptomycin dosing for peritonitis may be inadequate: a Monte Carlo simulation approach to optimize dosing and outcomes.

A two-compartmental mathematical pharmacokinetic model with first-order elimination of patients receiving CAPD of 4 exchanges for 6 h with 2 L of dialysate used in each cycle was developed to predict daptomycin disposition in 120 h of therapy. The pharmacodynamic target was plasma AUC/MIC equal to or greater than 666. The dose that achieved at least 90% of the probability of target attainment was defined as an optimal dose. Administering intraperitoneal 300 mg daily for 1 exchange daily regimen would be sufficient to treat peritonitis with S. aureus infection with MICs of 0.25 mg/L in patients undergoing CAPD. A higher dosage may be required for infections with a higher minimum inhibitory concentration. Pharmacodynamic targets and MICs significantly contributed to daptomycin doses in this setting. Clinical validation of our recommendations is recommended.

Persistence of Daptomycin-Resistant and Vancomycin-Resistant Enterococci in Hospitalized Patients with Underlying Malignancies: A 7-Year Follow-Up Study.

Vancomycin-resistant enterococci (VRE) commonly colonize the gut of individuals with hematologic malignancies or undergoing hematopoietic cell transplant (HCT) and may cause bacteremia. In 2012, we identified VRE isolates from patients and patients' rooms and showed transmission networks of highly genetically related daptomycin-resistant (DR)-VRE strains. This is a follow-up study performing whole-genome sequencing (WGS) and phylogenetic analyses on 82 clinical VRE strains isolated from stools and blood cultures of patients with leukemia and HCT between 2015 and 2019. Here, we observed transmission of highly genetically related strains between rooms on the same or on different floors, including a DR-VRE strain identified in 2012. Eleven of twenty-eight patients with DR-VRE were never exposed to daptomycin, suggesting horizontal transmission. Fifteen of the twenty-eight patients with DR-VRE died within 30 days of positive blood cultures. Amongst those, one DR-VRE strain belonging to ST1471 had the virulence gene bopD responsible for biofilm formation. Additionally, to our knowledge, this is the first report of a DR-VRE strain belonging to ST323 in the United States. In summary, our study demonstrated the emergence and persistence of VRE strains, especially DR-VRE, in our hospital. Adding WGS to routine infection control measures may timely identify potential horizontal VRE transmission including multi-drug-resistant isolates.

Put the Vanc Down, Flip It and Reverse It: Comparison of Vancomycin and Daptomycin Health Care Utilization and Cost in Outpatient Parenteral Antimicrobial Therapy.

Vancomycin and daptomycin are frequently used in outpatient parenteral antimicrobial therapy (OPAT). We analyze health care utilization and cost to the health care system for vancomycin vs daptomycin in the outpatient setting and find that vancomycin results in significantly higher health care utilization and similar cost per course compared with daptomycin in OPAT.

Combination of High-Dose Daptomycin and Ceftriaxone for Cardiac Implantable Electronic Device Infections: A 10-Year Experience.

PURPOSE: Cardiac implantable electronic device (CIED) infections are increasingly common. Gram-positive bacteria such as coagulase negative staphylococci and Staphylococcus aureus are the most commonly involved pathogens. The aim of this study was to describe the characteristics and outcome of patients with CIED infections who underwent device removal and were empirically treated with high dose (8-12 mg/kg daily) daptomycin (DAP) in combination with ceftriaxone (CRO). METHODS: Retrospective, single center study including patients admitted at IRCCS San Raffaele Hospital (Milan, Italy), from June 2011 to June 2021, who underwent device removal for CIED infection and were empirically treated with DAP/CRO. FINDINGS: Overall, 147 patients were included in this study. Median duration of therapy was 16 days (IQR 14-26). Empirical treatment with DAP/CRO was confirmed as definitive treatment in 140 patients (95.2%). In 7 (4.8%) patients DAP/CRO were discontinued according to the definite microbiological isolates: Corynebacterium spp. (4), Pseudomonas aeruginosa (2), Enterobacter cloacae (1). Ten patients (6.8%) underwent treatment simplification to narrow-spectrum antibiotics. One patient (0.6%) interrupted DAP-CRO due to pancytopenia. 6-month follow-up was available for 123/147 patients (83.7%): 9 patients recurred with a CIED infection (7.3%), and 9 died (7.3%). IMPLICATIONS: In our 10-year experience, high-dose DAP in combination with CRO represented a good option for empirical therapy of CIED infections. DAP-CRO combination was safe and effective, showing no significant drug-related adverse events and low rates of 6-month recurrence and mortality.

Association between age and onset of daptomycin-induced adverse events using the U.S. food and drug administration adverse event reporting system.

BACKGROUND: Daptomycin is a lipopeptide antibiotic with a broad spectrum of activity against gram-positive bacteria. Although information on daptomycin-induced adverse events can be found in clinical trials, data regarding the impact of age on these events are insufficient. Therefore, we evaluated whether age affects the occurrence of daptomycin-induced adverse events using adverse drug event reports in post-marketing stages provided by the U.S. Food and Drug Administration (FDA). METHODS: A total dataset of 7307 reports of patients treated with daptomycin in the FDA's Adverse Event Reporting System were analyzed. The patients were divided into seven age groups: 0-28 days, >28 days-23 months, 2-11 years, 12-17 years, 18-64 years, 65-80 years, and >80 years. A disproportionality analysis was conducted to calculate the reporting odds ratio, with a 95 % confidence interval. The univariate regression analysis was conducted using the percentage of each adverse event and age groups. RESULTS: Compared with the number of reports aged 18-64 years, there were significantly increased reports of eosinophilic pneumonia in patients aged 65-80 years and >80 years, anaphylactic reaction and pseudomembranous colitis in patients aged 12-17 years, and acute renal failure in patients aged 65-80 years. The regression coefficient for the reporting proportion of eosinophilic pneumonia was significantly positive. CONCLUSIONS: Our findings revealed age-related trends in daptomycin-induced adverse events, supporting the idea that implementing age-dependent follow-up and supportive care helps in the continuation of daptomycin therapy.

Daptomycin treatment for persistent bacteremia in a pediatric solid organ transplant recipient: Case report and literature review.

INTRODUCTION: Information on the clinical utility of daptomycin in patients with persistent bacteremia and daptomycin's pharmacokinetic data in pediatric patients has been sparse. In addition, reports on the experience of using daptomycin in children undergoing solid organ transplantation have been extremely limited. The authors describe a pediatric case of persistent bacteremia after solid organ transplantation successfully treated by daptomycin. Blood daptomycin concentrations were measured by liquid chromatography-mass spectrometry and pharmacokinetic analysis was performed. We also conducted a literature review on the use of daptomycin in children with persistent bacteremia. CASE REPORT: An eight-year-old girl who underwent small bowel and liver transplantation experienced persistent bacteremia due to Staphylococcus epidermidis. The bacteremia persisted despite standard therapy; however, it finally resolved with the addition of daptomycin. The patient had renal dysfunction and the initial dosing resulted in excessive drug exposure. The dosage was adjusted based on the pharmacokinetic analysis. The dosage of administrated teicoplanin was also adjusted according to trough concentration values. In the literature review, we identified 12 cases of neonates and 24 cases of post-neonatal children with the experience of using daptomycin for persistent bacteremia; however, no solid organ transplant recipient was identified. Similar trends in blood concentrations and dose ratios of teicoplanin and daptomycin were observed over time. DISCUSSION: More information is required regarding the clinical utility and pharmacokinetics of daptomycin in pediatric patients with persistent bacteremia. Referring to the exposure to renally excreted drugs that are routinely measured and pharmacokinetic analysis of daptomycin may be useful in optimizing the dose of daptomycin in special patient populations, including those with renal impairment.

Diagnosis and Management of Daptomycin-Induced Acute Eosinophilic Pneumonia: A Case Report.

Daptomycin is a cyclic lipopeptide antibiotic that is indicated for the treatment of complicated skin infections and bacteremia caused by gram positive organisms. Acute eosinophilic pneumonia (AEP) is a rare, but serious adverse effect of daptomycin and caused by accumulation of eosinophils in the lung tissues, and can lead to respiratory failure. Early diagnosis and management of this condition is crucial to avoid severe complications, including death. Herein, we report a case of an elderly man who presented with signs and symptoms of AEP within two weeks of initiation of daptomycin for the treatment of MRSA bacteremia. The patient showed significant clinical improvement and decline in eosinophils upon discontinuation of daptomycin and starting a 5-day steroid course. Acute eosinophilic pneumonia should be kept in mind as a possible, although rare, adverse effect of daptomycin. Early recognition can be established through typical symptoms, eosinophilia, and chest X-ray showing pulmonary infiltrate. Rapid discontinuation of daptomycin with/without steroid therapy and supportive care usually results in significant clinical recover.

Daptomycin eosinophilic pneumonia, a systematic review of the literature and case series.

PURPOSE: Daptomycin-induced eosinophilic pneumonia (DIEP) is a rare yet severe adverse event that requires rapid recognition and management. Diagnosing a definite case is challenging and involves meeting the American Thoracic Society (ATS) criteria, although alternative criteria have been suggested. This study aims to conduct a systematic review of literature and includes a case series. METHODS: Six cases of DIEP identified at Perugia Hospital, Perugia, Italy have been described. A systematic review was carried out adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement guidelines. RESULTS: a total of 74 cases of DIEP were analysed. Using ATS clinical criteria, 15 were classified as definite (20.3%), 54 as probable (73.0%), and 5 as possible (6.8%). Phillips criteria and the Lyon Algorithm identified 43/74 (58.2%) and 64/67 (95.5%) cases as definite, respectively. Bronchoalveolar lavage (BAL) was performed in 43 cases, revealing an average eosinophil count of 28.6% (SD 24.4). Radiological findings highlighted recurring features like bilateral opacities (68.1%), ground-glass opacities (41.7%), patchy infiltrates (30.6%), and peripheral predominance (19.4%). Upon suspicion, daptomycin was discontinued; 20 cases required no additional treatment, 38 received corticosteroids, and 12 received both corticosteroids and antibiotics. Recovery rates were high across all treatment types (≥ 73.7%). Most reports described rapid improvement post-withdrawal (within 96 h). CONCLUSIONS: DIEP is a rare, fast-progressing condition where early diagnosis and prompt treatment are vital. Diagnosis relies on clinical, laboratory, and radiological evaluations. Stopping daptomycin is essential, with corticosteroids often necessary. Further research is needed to enhance diagnostic accuracy for this disease.

Fixed dose daptomycin: An opportunity for pharmacokinetic/pharmacodynamic optimization in Staphylococcus aureus infections.

BACKGROUND: Daptomycin is a high-use intravenous antimicrobial agent affording the convenience of once-daily dosing. Prior studies suggest an opportunity to use a more operationally convenient fixed rather than weight-based dosing but this approach has not been studied prospectively. METHODS: This study quantified the probability of toxicity and efficacy end points by prospectively testing a fixed dose regimen of daptomycin (750 mg) in obese and non-obese adults. At least, three daptomycin concentrations were measured at steady-state for each patient. A population pharmacokinetic model was constructed to evaluate concentration-time profiles and investigate covariates of daptomycin clearance. Simulations were performed to evaluate the probability of achieving efficacy (24-h area under the curve (AUC0-24) ≥ 666 mg∙h/L) and toxicity (minimum concentration (C min) ≥24.3 mg/L) targets for fixed (500-1000 mg) and weight-based (6-12 mg/kg) daptomycin doses. RESULTS: Thirty-one patients (16 females, 15 males) with median (interquartile range (IQR)) age of 50 (30, 62) years and weight of 74 (54, 156) kg were included in the final analysis. Fixed dose daptomycin (750 mg) resulted in similar exposure across weights with a median (IQR) AUC0-24 of 819 (499, 1501) mg∙h/L and 749 (606, 1265) mg∙h/L in patients weighing ≤74 kg and >74 kg, respectively. Overall, male sex and increased kidney function necessitate higher fixed and weight-based doses to achieve efficacy. Creatine phosphokinase elevation was observed in two patients (6.5%) and predicted to be lower with fixed versus weight-based regimens. CONCLUSIONS: Fixed daptomycin dosing adjusted for sex and kidney function is expected to improve the efficacy-to-toxicity ratio, transitions of care, and costs compared to weight-based doses. However, no empiric dosing approach is predicted to achieve ≥90% efficacy while minimizing the risk of toxicity, so therapeutic drug monitoring should be considered on a patient-specific basis.

A Case of Confusion in an Obese Patient Treated With Daptomycin: Neurotoxicity.

Daptomycin (DAP) is a cyclic lipopeptide antibiotic with bactericidal activity against gram-positive bacteria. The most common adverse reaction is myotoxicity characterized by rhabdomyolysis. Other reported adverse reactions include gastrointestinal symptoms, skin lesions, bleeding, and pulmonary involvement. Neurotoxicity is rare and its mechanism remains partially elucidated. We report a case of confusion consistent with DAP-induced neurotoxicity. A 73-year-old obese man was treated with DAP 9 mg/kg for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia associated with foot osteitis and cervical posterior inter-apophyseal arthritis. On the fifth day of treatment, he developed spatial disorientation, and serum DAP concentrations were very high. DAP-induced neurotoxicity was suggested. His neurological status returned to normal after treatment was stopped. This observation describes a relationship between confusion and DAP that is favored by obesity. Clinicians should be alert for neurologic disorders associated with DAP. It is prudent to reduce doses in obese patients.

Development and ELISA Characterization of Antibodies against the Colistin, Vancomycin, Daptomycin, and Meropenem: A Therapeutic Drug Monitoring Approach.

More than 70% of bacteria are resistant to all or nearly all known antimicrobials, creating the need for the development of new types of antimicrobials or the use of "last-line" antimicrobial therapies for the treatment of multi-resistant bacteria. These antibiotics include Glycopeptide (Vancomycin), Polymyxin (Colistin), Lipopeptide (Daptomycin), and Carbapenem (Meropenem). However, due to the toxicity of these types of molecules, it is necessary to develop new rapid methodologies to be used in Therapeutic Drug Monitoring (TDM). TDM could improve patient outcomes and reduce healthcare costs by enabling a favorable clinical outcome. In this way, personalized antibiotic therapy emerges as a viable option, offering optimal dosing for each patient according to pharmacokinetic (PK) and pharmacodynamic (PD) parameters. Various techniques are used for this monitoring, including high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), and immunoassays. The objective of this study is the development and characterization by ELISA of specific polyclonal antibodies for the recognition of the antibiotics Vancomycin (glycopeptide), Colistin (polymyxin), Daptomycin (lipopeptide), and Meropenem (carbapenem) for future applications in the monitoring of these antibiotics in different fluids, such as human plasma. The developed antibodies are capable of recognizing the antibiotic molecules with good detectability, showing an IC50 of 0.05 nM for Vancomycin, 7.56 nM for Colistin, 183.6 nM for Meropenem, and 13.82 nM for Daptomycin. These antibodies offer a promising tool for the precise and effective therapeutic monitoring of these critical antibiotics, potentially enhancing treatment efficacy and patient safety.

Dual release of daptomycin and BMP-2 from a composite of ß-TCP ceramic and ADA gelatin.

BACKGROUND: Antibiotic-containing carrier systems are one option that offers the advantage of releasing active ingredients over a longer period of time. In vitro sustained drug release from a carrier system consisting of microporous ß-TCP ceramic and alginate has been reported in previous works. Alginate dialdehyde (ADA) gelatin gel showed both better mechanical properties when loaded into a ß-TCP ceramic and higher biodegradability than pure alginate. METHODS: Dual release of daptomycin and BMP-2 was measured on days 1, 2, 3, 6, 9, 14, 21, and 28 by HPLC and ELISA. After release, the microbial efficacy of the daptomycin was verified and the biocompatibility of the composite was tested in cell culture. RESULTS: Daptomycin and the model compound FITC protein A (n = 30) were released from the composite over 28 days. A Daptomycin release above the minimum inhibitory concentration (MIC) by day 9 and a burst release of 71.7 ± 5.9% were observed in the loaded ceramics. Low concentrations of BMP-2 were released from the loaded ceramics over 28 days.

Counting the Cost of Daptomycin Versus Vancomycin in Hospitalized Patients: A Cost Minimization Analysis.

Daptomycin use for gram-positive infections has increased. This cost minimization analysis aimed to determine cost and/or time savings of daptomycin over vancomycin. The estimated hospital cost savings was US$166.41 per patient, and pharmacist time saved of almost 20 minutes per patient. Daptomycin has the potential to save both time and money.