scholarly journals Reduced susceptibility to daptomycin in methicillin-resistant Staphylococcus aureus isolated from catheter-related bloodstream infections

Author(s):  
Sho Ohyatsu ◽  
Tomoyuki Nariyama ◽  
Kotaro Matsumoto ◽  
Yuki Moritoki ◽  
Kentaro Kikuchi

Abstract Background The appearance of reduced susceptibility to daptomycin in methicillin-resistant Staphylococcus aureus (MRSA) has recently been reported. It is unclear how likely MRSA involved in catheter-related bloodstream infections (CRBSI) is to dampen susceptibility to daptomycin. We investigated the minimum inhibitory concentrations (MIC) of daptomycin in MRSA isolated from the blood of patients with CRBSI and examined how it was affected by previous anti-MRSA drug treatment. Methods A total of 115 patients whose blood culture samples were found to contain MRSA were enrolled in this study. The MIC of daptomycin and vancomycin and whether the subjects had a history of anti-MRSA drug treatment were investigated and compared between the CRBSI and non-CRBSI groups. Results The mean MIC of daptomycin was significantly higher for the 46 CRBSI-related MRSA isolates than for the 69 non-CRBSI-related MRSA isolates (0.78 vs. 0.33, respectively; p<0.0001). Among the CRBSI-related MRSA isolates, those collected from patients with a history of anti-MRSA drug treatment had significantly higher MIC (1.27 vs. 0.53, respectively; p <0.01). During treatment, MRSA was detected again in 10 CRBSI and 4 non-CRBSI patients, and all of the CRBSI-related MRSA isolates exhibited 1-2 log2 increases in their daptomycin MIC. Conclusions It is considered that when MRSA in catheter biofilms is exposed to anti-MRSA drugs, strains with reduced susceptibility to daptomycin are able to survive and disperse into the blood. Catheters should be removed if an MRSA-induced CRBSI is suspected. Further study of whether high-dose daptomycin treatment is effective when catheters cannot be immediately removed is needed.

Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 395
Author(s):  
Katarina Pomorska ◽  
Vladislav Jakubu ◽  
Lucia Malisova ◽  
Marta Fridrichova ◽  
Martin Musilek ◽  
...  

Staphylococcus aureus is one of the major causes of bloodstream infections. The aim of our study was to characterize methicillin-resistant Staphylococcus aureus (MRSA) isolates from blood of patients hospitalized in the Czech Republic between 2016 and 2018. All MRSA strains were tested for antibiotic susceptibility, analyzed by spa typing and clustered using a Based Upon Repeat Pattern (BURP) algorithm. The representative isolates of the four most common spa types and representative isolates of all spa clonal complexes were further typed by multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing. The majority of MRSA strains were resistant to ciprofloxacin (94%), erythromycin (95.5%) and clindamycin (95.6%). Among the 618 strains analyzed, 52 different spa types were detected. BURP analysis divided them into six different clusters. The most common spa types were t003, t586, t014 and t002, all belonging to the CC5 (clonal complex). CC5 was the most abundant MLST CC of our study, comprising of 91.7% (n = 565) of spa-typeable isolates. Other CCs present in our study were CC398, CC22, CC8, CC45 and CC97. To our knowledge, this is the biggest nationwide study aimed at typing MRSA blood isolates from the Czech Republic.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S143-S144
Author(s):  
Michelle Vu ◽  
Kenneth Smith ◽  
Sherrie L Aspinall ◽  
Cornelius J Clancy ◽  
Deanna Buehrle

Abstract Background Methicillin-resistant Staphylococcus aureus bloodstream infections (MRSAB) cause significant mortality and often require extended antibiotic therapy. Vancomycin, the most common initial MRSAB treatment, carries significant monitoring burden and nephrotoxicity risks. We compared cost-effectiveness of vancomycin and other antibiotic regimens as MRSAB treatment. Methods We estimated cost-effectiveness of intravenous antibiotics (vancomycin, daptomycin, linezolid, ceftaroline/daptomycin, dalbavancin) for Veterans Health Administration (VA) patients with MRSAB using an exploratory decision-tree model. Primary effectiveness outcome was composite of microbiological failure and adverse drug event (ADE)-related discontinuation at 7-days. Results In base-case analyses, linezolid and daptomycin were less expensive and had fewer treatment failures than other regimens at 4 and 6-weeks. Compared to linezolid, daptomycin incremental cost-effectiveness ratios were ~$45,000 (4-weeks) and ~$61,000 (6-weeks) per composite failure avoided, respectively. In one-way sensitivity analyses, daptomycin (4-weeks) was favored over linezolid if linezolid microbiological failure or ADE-related discontinuation rates were &gt;14.8% (base case: 14.0%) or &gt;14.3% (base case: 14.0%), respectively, assuming a willingness to pay (WTP) threshold of $40,000/ composite treatment failure avoided. Vancomycin was favored if its microbiological failure risk was &lt; 16.4% (base case: 27.2%). In two-way sensitivity analyses, daptomycin was favored if linezolid microbiological failure and ADE-related discontinuation rates were &gt;19% and &gt; 16%, respectively. Linezolid, daptomycin and vancomycin were favored in 47%, 39%, and 11% of 4-week probabilistic iterations, respectively, at $40,000 WTP. Conclusion Daptomycin or linezolid are likely less expensive and more effective than vancomycin or other initial regimens for MRSAB. More data are needed to support safety of linezolid in MRSAB patients. Disclosures Cornelius J. Clancy, MD, Astellas (Consultant, Grant/Research Support)Cidara (Consultant, Research Grant or Support)Melinta (Grant/Research Support)Merck (Consultant, Grant/Research Support)Needham Associates (Consultant)Qpex (Consultant)Scynexis (Consultant)Shionogi (Consultant)


Author(s):  
Evan J Zasowski ◽  
Trang D Trinh ◽  
Kimberly C Claeys ◽  
Abdalhamid M Lagnf ◽  
Sahil Bhatia ◽  
...  

Abstract Background Observational data suggest ceftaroline may be effective for methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSI) but comparative data with standard of care are limited. This analysis compares the outcomes of MRSA BSI treated with ceftaroline or daptomycin. Methods Multicenter, retrospective, observational cohort study of adult patients with MRSA BSI from 2010 to 2017. Patients treated with ≥ 72 hours of ceftaroline or daptomycin were included. Those clearing BSI before study drug and those with a pneumonia source were excluded. The primary outcome was composite treatment failure, defined as 30-day mortality, BSI duration ≥ 7 days on study drug, and 60-day MRSA BSI recurrence. Inverse probability of treatment weighted risk difference in composite failure between daptomycin and ceftaroline groups was computed and 15% non-inferiority margin applied. Results Two hundred seventy patients were included; 83 ceftaroline and 187 daptomycin. Ceftaroline was non-inferior to daptomycin with respect to composite failure [39% daptomycin, 32.5% ceftaroline; weighted risk difference (95% CI) 7.0% (-5.0 – 19.0%)]. No differences between treatment groups was observed for 30-day mortality or other secondary efficacy outcomes. Creatine phosphokinase elevation was significantly more common among daptomycin patients (5.3% vs 0%, P = 0.034). Rash was significantly more common among ceftaroline patients (10.8 vs 1.1%, P = 0.001). Conclusions No difference in treatment failure or mortality was observed between MRSA BSI treated with ceftaroline or daptomycin. These data support future study of ceftaroline as a primary MRSA BSI treatment and current use of ceftaroline when an alternative to vancomycin and daptomycin is required.


2021 ◽  
pp. 114-118
Author(s):  
Raghavendra Rao M. V ◽  
Mubasheer Ali ◽  
Yogendra Kumar Verma ◽  
Dilip Mathai ◽  
Tina Priscilla ◽  
...  

Methicillin-resistant Staphylococcus aureus (MRSA) is difcult to treat with methicillin, amoxicillin, penicillin, oxacillin, and other commonly used antibiotics because of its resistance. Staphylococcus organisms rapidly develop drug resistance as many as 50% of the domiciliary and 80% of the hospital strains are now penicillin resistant. Staphylococcus aureus also show multiple drug resistance. Therefore, Staphylococcal isolates should always be tested for antimicrobial sensitivity and chronic infection should be treated by more than one drug. Before 1960,when methicillin, is the rst penicillin's-resistant penicillin's, was brought into use, about 1%of the strains of the Staphylococcus aureus were "methicillin resistant" and by 1970 in Britain their proportion has risen to about 5%.These strains are tolerant of, low therapeutic concentrations of methicillin, cloxacillin, benzyl penicillin and ampicillin.They do not destroy methicillin and cloxacillin, but most of them are penicillinase-producing as well as being "methicillin resistant" and therefore inactivate benzyl penicillin and ampicillin. Its resistance is uncertain since infections may be cured with a high dose of methicillin.


2019 ◽  
Vol 71 (5) ◽  
pp. 1142-1148 ◽  
Author(s):  
Kari A Mergenhagen ◽  
Kaitlyn E Starr ◽  
Bethany A Wattengel ◽  
Alan J Lesse ◽  
Zarchi Sumon ◽  
...  

Abstract Background Treatment of suspected methicillin-resistant Staphylococcus aureus (MRSA) is a cornerstone of many antibiotic regimens; however, there is associated toxicity. The Department of Veterans Affairs (VA) hospitals screen each patient for MRSA nares colonization on admission and transfer. The objective was to determine the negative predictive value (NPV) of MRSA screening in the determination of subsequent positive clinical culture for MRSA. High NPVs with MRSA nares screening may be used as a stewardship tool. Methods This was a retrospective cohort study across VA medical centers nationwide from 1 January 2007 to 1 January 2018. Data from patients with MRSA nares screening were obtained from the VA Corporate Data Warehouse. Subsequent clinical cultures within 7 days of the nares swab were evaluated for the presence of MRSA. Sensitivity, specificity, positive predictive values, and NPVs were calculated for the entire cohort as well as subgroups for specific culture sites. Results This cohort yielded 561 325 clinical cultures from a variety of anatomical sites. The sensitivity and specificity for positive MRSA clinical culture were 67.4% and 81.2%, respectively. The NPV of MRSA nares screening for ruling out MRSA infection was 96.5%. The NPV for bloodstream infections was 96.5%, for intraabdominal cultures it was 98.6%, for respiratory cultures it was 96.1%, for wound cultures it was 93.1%, and for cultures from the urinary system it was 99.2%. Conclusion Given the high NPVs, MRSA nares screening may be a powerful stewardship tool for deescalation and avoidance of empirical anti-MRSA therapy.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S769-S769
Author(s):  
Sarah C J Jorgensen ◽  
Trang D Trinh ◽  
Evan J Zasowski ◽  
Sara Alosaimy ◽  
Sarah Melvin ◽  
...  

Abstract Background Combination β-lactam and vancomycin (VAN) prevent the emergence of resistance and result in synergistic antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) in vitro. We sought to provide clinical translation to these data and determine if patients with MRSA bloodstream infection (BSI) treated with VAN + cefazolin (VAN/CFZ) via our MRSA BSI clinical pathway had improved clinical outcomes compared VAN alone. Methods Multicenter, retrospective, comparative cohort study from 2006 to 2019 in adults with MRSA BSI treated with VAN for ≥ 72 hours. VAN/CFZ was defined as VAN + CFZ within ≤ 72 hours of index culture for ≥ 24 hours. Other β-lactams were allowed for < 48 h in the VAN/CFZ group. The VAN alone group could not have other β-lactams within 7 days of treatment initiation. The primary outcome was clinical failure defined as a composite of 30-d all-cause mortality, 60-day recurrence, and persistent BSI (≥ 7 days). The independent effect of VAN/CFZ on clinical failure was evaluated with multivariable logistic regression. The primary safety endpoint was nephrotoxicity within 7 days of treatment initiation. Results A total of 237 patients were included (104 VAN/CFZ, 133 VAN). The most common BSI sources were skin/soft tissue (29.1%), IV catheter (21.9%), osteoarticular (20.3%) and infective endocarditis (16.0%). Demographic and clinical characteristics were similar between groups except VAN/CFZ had a higher median APACHE II score (18 vs. 13, P = 0.011). VAN/CFZ patients were also more likely to have received an infectious disease consult (100% vs. 81.2%, P < 0.001). Median (IQR) duration of CFZ was 115 (87–164) hours. After controlling for age, APACHE II score, ID consult and infection source, VAN/CFZ was associated with reduced odds of clinical failure (aOR 0.425, 95% CI 0.228, 0.792). Bivariate outcomes are shown in the table: Conclusion Patients with MRSA BSI treated with VAN/CFZ vs. VAN experienced fewer clinical failures, supporting additional studies evaluating the role of adjuvant CFZ for MRSA BSI. Disclosures All authors: No reported disclosures.


Sign in / Sign up

Export Citation Format

Share Document