Evaluation of a new Rapid Antimicrobial Susceptibility system for Gram-negative and Gram-positive bloodstream infections: Speed and accuracy of Alfred 60 AST

Abstract Background: Blood stream infections (BSIs) are a major cause of morbidity and mortality. The time from taking blood cultures to obtain results of antibiotic sensitivity can be up to five days which impacts patient care. The Alfred 60 AST™ can reduce laboratory time from positive culture bottle to susceptibility results from 16-25 hours to 5-6 hours, transforming patient care. To evaluate the diagnostic accuracy of a rapid antimicrobial susceptibility system, the Alfred 60 AST™, in clinical isolates from patients with BSIs and confirm time to results. 301 Gram-negative and 86 Gram-positive isolates were analysed directly from positive blood culture bottles following Gram staining. Antimicrobial susceptibility results and time-to-results obtained by rapid Alfred 60 AST system and BD Phoenix were compared . Results: A total of 2,196 antimicrobial susceptibility test results (AST) were performed: 1,863 Gram-negative and 333 Gram-positive. AST categorical agreement (CA) for Alfred 60 AST™ was 95% (1772/1863) for Gram-negative and 89% (295/333) for Gram-positive isolates. Gram-negative CA: ampicillin 96% (290/301); ciprofloxacin 95% (283/297); ceftriaxone 96% (75/78); meropenem 97% (288/297); piperacillin-tazobactam 95% (280/295); gentamicin 94% (279/297) and amikacin 93% (277/298). The median time to susceptibility results from blood culture flagging positive was 6.3 h vs 20 h (p<0.01) for Alfred system vs BD Phoenix™. Conclusion: Alfred 60 AST system greatly reduced time to antimicrobial susceptibility results in Gram-negative and Gram-positive BSIs with good performance and cost, particularly for Gram-negative bacteraemia. Keywords: Rapid diagnostics. Bloodstream infection. Bacteraemia. Antimicrobial susceptibility testing. Gram-negative bacteria. Gram-positive bacteria

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Evaluation of a new Rapid Antimicrobial Susceptibility system for Gram-negative and Gram-positive bloodstream infections: Speed and accuracy of Alfred 60 AST

10.21203/rs.2.10509/v2 ◽

2019 ◽

Author(s):

Vanesa Anton-Vazquez ◽

Adjepong Samuel ◽

Suarez Cristina ◽

Planche Timothy

Keyword(s):

Blood Culture ◽

Patient Care ◽

Antimicrobial Susceptibility ◽

Antibiotic Sensitivity ◽

Positive Culture ◽

Bloodstream Infections ◽

Rapid Diagnostics ◽

Gram Positive ◽

Culture Bottle ◽

Gram Negative

Abstract Background: Blood stream infections (BSIs) are a major cause of morbidity and mortality. The time from taking blood cultures to obtain results of antibiotic sensitivity can be up to five days which impacts patient care. The Alfred 60 AST™ can reduce laboratory time from positive culture bottle to susceptibility results from 16-25 hours to 5-6 hours, transforming patient care. Objective: To evaluate the diagnostic accuracy of a rapid antimicrobial susceptibility system, the Alfred 60 AST™, in clinical isolates from patients with BSIs and confirm time to results. Methods: 301 Gram-negative and 86 Gram-positive isolates were analysed directly from positive blood culture bottles following Gram staining. Antimicrobial susceptibility results and time-to-results obtained by rapid Alfred 60 AST system and BD Phoenix were compared . Results : A total of 2,196 antimicrobial susceptibility test results (AST) were performed: 1,863 Gram-negative and 333 Gram-positive. AST categorical agreement (CA) for Alfred 60 AST™ was 95% (1772/1863) for Gram-negative and 89% (295/333) for Gram-positive isolates. Gram-negative CA: ampicillin 96% (290/301); ciprofloxacin 95% (283/297); ceftriaxone 96% (75/78); meropenem 97% (288/297); piperacillin-tazobactam 95% (280/295); gentamicin 94% (279/297) and amikacin 93% (277/298). The median time to susceptibility resultsfrom blood culture flagging positive was 6.3 h vs 20 h ( p<0.01 ) for Alfred system vs BD Phoenix™. Conclusion: Alfred 60 AST system greatly reduced time to antimicrobial susceptibility results in Gram-negative and Gram-positive BSIs with good performance and cost, particularly for Gram-negative bacteraemia. Keywords: Rapid diagnostics. Bloodstream infection. Bacteraemia. Antimicrobial susceptibility testing. Gram-negative bacteria. Gram-positive bacteria

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Evaluation of a new Rapid Antimicrobial Susceptibility system for Gram-negative and Gram-positive bloodstream infections: Speed and accuracy of Alfred 60 AST

10.21203/rs.2.10509/v3 ◽

2019 ◽

Author(s):

Vanesa Anton-Vazquez ◽

Adjepong Samuel ◽

Suarez Cristina ◽

Planche Timothy

Keyword(s):

Blood Culture ◽

Patient Care ◽

Antimicrobial Susceptibility ◽

Antibiotic Sensitivity ◽

Positive Culture ◽

Bloodstream Infections ◽

Rapid Diagnostics ◽

Gram Positive ◽

Culture Bottle ◽

Gram Negative

Abstract Background: Blood stream infections (BSIs) are a major cause of morbidity and mortality. The time from taking blood cultures to obtain results of antibiotic sensitivity can be up to five days which impacts patient care. The Alfred 60 AST™ can reduce laboratory time from positive culture bottle to susceptibility results from 16-25 hours to 5-6 hours, transforming patient care. Objective: To evaluate the diagnostic accuracy of a rapid antimicrobial susceptibility system, the Alfred 60 AST™, in clinical isolates from patients with BSIs and confirm time to results. Methods: 301 Gram-negative and 86 Gram-positive isolates were analysed directly from positive blood culture bottles following Gram staining. Antimicrobial susceptibility results and time-to-results obtained by rapid Alfred 60 AST system and BD Phoenix were compared . Results : A total of 2,196 antimicrobial susceptibility test results (AST) were performed: 1,863 Gram-negative and 333 Gram-positive. AST categorical agreement (CA) for Alfred 60 AST™ was 95% (1772/1863) for Gram-negative and 89% (295/333) for Gram-positive isolates. Gram-negative CA: ampicillin 96% (290/301); ciprofloxacin 95% (283/297); ceftriaxone 96% (75/78); meropenem 97% (288/297); piperacillin-tazobactam 95% (280/295); gentamicin 94% (279/297) and amikacin 93% (277/298). The median time to susceptibility resultsfrom blood culture flagging positive was 6.3 h vs 20 h ( p<0.01 ) for Alfred system vs BD Phoenix™. Conclusion: Alfred 60 AST system greatly reduced time to antimicrobial susceptibility results in Gram-negative and Gram-positive BSIs with good performance and cost, particularly for Gram-negative bacteraemia. Keywords: Rapid diagnostics. Bloodstream infection. Bacteraemia. Antimicrobial susceptibility testing. Gram-negative bacteria. Gram-positive bacteria

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Evaluation of a new Rapid Antimicrobial Susceptibility system for Gram-negative and Gram-positive bloodstream infections: Speed and accuracy of Alfred 60 AST

10.21203/rs.2.10509/v1 ◽

2019 ◽

Author(s):

Vanesa Anton-Vazquez ◽

Adjepong Samuel ◽

Suarez Cristina ◽

Planche Timothy

Keyword(s):

Blood Culture ◽

Patient Care ◽

Antimicrobial Susceptibility ◽

Antibiotic Sensitivity ◽

Positive Culture ◽

Bloodstream Infections ◽

Blood Stream ◽

Gram Positive ◽

Culture Bottle ◽

Gram Negative

Abstract Background Blood stream infections (BSIs) are a major cause of morbidity and mortality. The time from taking blood cultures to obtain results of antibiotic sensitivity can be up to five days which impacts patient care. The Alfred 60 AST™ can reduce laboratory time from positive culture bottle to susceptibility results from 16-25 hours to 5-6 hours, transforming patient care. Objective To evaluate the diagnostic accuracy of a rapid antimicrobial susceptibility system, the Alfred 60 AST™, in clinical isolates from patients with BSIs and confirm time to results. Methods 301 Gram-negative and 86 Gram-positive isolates were analysed directly from positive blood culture bottles following Gram staining. Antimicrobial susceptibility results and time-to-results obtained by rapid Alfred 60 AST system and BD Phoenix were compared . Results A total of 2,196 antimicrobial susceptibility test results (AST) were performed: 1,863 Gram-negative and 333 Gram-positive. AST categorical agreement (CA) for Alfred 60 AST™ was 95% (1772/1863) for Gram-negative and 89% (295/333) for Gram-positive isolates. Gram-negative CA: ampicillin 96% (290/301); ciprofloxacin 95% (283/297); ceftriaxone 96% (75/78); meropenem 97% (288/297); piperacillin-tazobactam 95% (280/295); gentamicin 94% (279/297) and amikacin 93% (277/298). The median time to susceptibility results from blood culture flagging positive was 6.3 h vs 20 h (p<0.01) for Alfred system vs BD Phoenix™. Conclusion Alfred 60 AST system greatly reduced time to antimicrobial susceptibility results in Gram-negative and Gram-positive BSIs with good performance and cost, particularly for Gram-negative bacteraemia.

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Evaluation of a new Rapid Antimicrobial Susceptibility system for Gram-negative and Gram-positive bloodstream infections: speed and accuracy of Alfred 60AST

BMC Microbiology ◽

10.1186/s12866-019-1654-9 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 3

Author(s):

Vanesa Anton-Vazquez ◽

Samuel Adjepong ◽

Cristina Suarez ◽

Timothy Planche

Keyword(s):

Blood Culture ◽

Patient Care ◽

Antimicrobial Susceptibility ◽

Antibiotic Sensitivity ◽

Positive Culture ◽

Bloodstream Infections ◽

Blood Stream ◽

Gram Positive ◽

Culture Bottle ◽

Gram Negative

Abstract Background Blood stream infections (BSIs) are a major cause of morbidity and mortality. The time from taking blood cultures to obtain results of antibiotic sensitivity can be up to five days which impacts patient care. The Alfred 60 AST™ can reduce laboratory time from positive culture bottle to susceptibility results from 16 to 25 h to 5–6 h, transforming patient care. To evaluate the diagnostic accuracy of a rapid antimicrobial susceptibility system, the Alfred 60 AST™, in clinical isolates from patients with BSIs and confirm time to results. 301 Gram-negative and 86 Gram-positive isolates were analysed directly from positive blood culture bottles following Gram staining. Antimicrobial susceptibility results and time-to-results obtained by rapid Alfred 60 AST system and BD Phoenix were compared . Results A total of 2196 antimicrobial susceptibility test results (AST) were performed: 1863 Gram-negative and 333 Gram-positive. AST categorical agreement (CA) for Alfred 60 AST™ was 95% (1772/1863) for Gram-negative and 89% (295/333) for Gram-positive isolates. Gram-negative CA: ampicillin 96% (290/301); ciprofloxacin 95% (283/297); ceftriaxone 96% (75/78); meropenem 97% (288/297); piperacillin-tazobactam 95% (280/295); gentamicin 94% (279/297) and amikacin 93% (277/298). The median time to susceptibility results from blood culture flagging positive was 6.3 h vs 20 h (p < 0.01) for Alfred system vs BD Phoenix™. Conclusion Alfred 60 AST system greatly reduced time to antimicrobial susceptibility results in Gram-negative and Gram-positive BSIs with good performance and cost, particularly for Gram-negative bacteraemia.

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Identification and antimicrobial susceptibility testing of Gram-positive and Gram-negative bacteria from positive blood cultures using the Accelerate Pheno™ system

European Journal of Clinical Microbiology & Infectious Diseases ◽

10.1007/s10096-019-03703-y ◽

2019 ◽

Vol 39 (1) ◽

pp. 139-149 ◽

Cited By ~ 1

Author(s):

Måns Ullberg ◽

Volkan Özenci

Keyword(s):

Blood Culture ◽

Antimicrobial Susceptibility ◽

Susceptibility Testing ◽

Bloodstream Infections ◽

Blood Cultures ◽

Antimicrobial Susceptibility Testing ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Hands On

Abstract Rapid identification and antimicrobial susceptibility testing remain a crucial step for early efficient therapy of bloodstream infections. Traditional methods require turnaround times of at least 2 days, while rapid procedures are often associated with extended hands-on time. The Accelerate Pheno™ System provides microbial identification results within 90 min and susceptibility data in approximately 7 h directly from positive blood cultures with only few minutes of hands-on time. The aim of this study was, therefore, to evaluate the performance of the Accelerate Pheno™ System in identification and antimicrobial susceptibility testing of both Gram-positive and Gram-negative bacteria directly from clinical blood culture samples. We analyzed 108 and 67 blood culture bottles using the Accelerate PhenoTest™ BC kit with software version v1.0 and the FDA-cleared version v1.2, respectively. Reliable identification was achieved for Enterobacteriaceae, staphylococci, and enterococci, with 76/80 (95%), 42/46 (91%), and 10/11 (91%) correct identifications. Limitations were observed in the identification of streptococci, including Streptococcus pneumoniae and Streptococcus pyogenes, and coagulase-negative staphylococci. Antimicrobial susceptibility results for Enterobacteriaceae, for amikacin, ertapenem, ciprofloxacin, gentamicin, meropenem, and piperacillin-tazobactam ranged between 86 and 100% categorical agreement. Using v1.2, results for ceftazidime showed 100% concordance with the reference method. For staphylococci, the overall performance reached 92% using v1.2. Qualitative tests for detection of methicillin or macrolide-lincosamide-streptogramin B (MLSB) resistance caused major and very major errors for isolates. Overall, the present data show that the Accelerate Pheno™ system can, in combination with Gram stain, be used as a rapid complementation to standard microbial diagnosis of bloodstream infections.

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Evaluation of the Accelerate Pheno System for Fast Identification and Antimicrobial Susceptibility Testing from Positive Blood Cultures in Bloodstream Infections Caused by Gram-Negative Pathogens

Journal of Clinical Microbiology ◽

10.1128/jcm.00181-17 ◽

2017 ◽

Vol 55 (7) ◽

pp. 2116-2126 ◽

Cited By ~ 84

Author(s):

Matthias Marschal ◽

Johanna Bachmaier ◽

Ingo Autenrieth ◽

Philipp Oberhettinger ◽

Matthias Willmann ◽

...

Keyword(s):

Blood Culture ◽

Antimicrobial Susceptibility ◽

Susceptibility Testing ◽

Bloodstream Infections ◽

Test System ◽

Blood Cultures ◽

Antimicrobial Susceptibility Testing ◽

Diagnostic Tools ◽

Gram Negative ◽

Content Type

ABSTRACT Bloodstream infections (BSI) are an important cause of morbidity and mortality. Increasing rates of antimicrobial-resistant pathogens limit treatment options, prompting an empirical use of broad-range antibiotics. Fast and reliable diagnostic tools are needed to provide adequate therapy in a timely manner and to enable a de-escalation of treatment. The Accelerate Pheno system (Accelerate Diagnostics, USA) is a fully automated test system that performs both identification and antimicrobial susceptibility testing (AST) directly from positive blood cultures within approximately 7 h. In total, 115 episodes of BSI with Gram-negative bacteria were included in our study and compared to conventional culture-based methods. The Accelerate Pheno system correctly identified 88.7% (102 of 115) of all BSI episodes and 97.1% (102 of 105) of isolates that are covered by the system's identification panel. The Accelerate Pheno system generated an AST result for 91.3% (95 of 104) samples in which the Accelerate Pheno system identified a Gram-negative pathogen. The overall category agreement between the Accelerate Pheno system and culture-based AST was 96.4%, the rates for minor discrepancies 1.4%, major discrepancies 2.3%, and very major discrepancies 1.0%. Of note, ceftriaxone, piperacillin-tazobactam, and carbapenem resistance was correctly detected in blood culture specimens with extended-spectrum beta-lactamase-producing Escherichia coli ( n = 7) and multidrug-resistant Pseudomonas aeruginosa ( n = 3) strains. The utilization of the Accelerate Pheno system reduced the time to result for identification by 27.49 h ( P < 0.0001) and for AST by 40.39 h ( P < 0.0001) compared to culture-based methods in our laboratory setting. In conclusion, the Accelerate Pheno system provided fast, reliable results while significantly improving turnaround time in blood culture diagnostics of Gram-negative BSI.

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A comparative study of bloodstream infections in acute myeloid leukemia according to different phases of treatment: Can we predict the organism?

South Asian Journal of Cancer ◽

10.4103/2278-330x.214584 ◽

2017 ◽

Vol 06 (03) ◽

pp. 132-133

Author(s):

Preetam Kalaskar ◽

Asha Anand ◽

Harsha Panchal ◽

Apurva Patel ◽

Sonia Parikh ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Blood Culture ◽

Myeloid Leukemia ◽

Bloodstream Infections ◽

Blood Cultures ◽

Consolidation Therapy ◽

Gram Positive ◽

Gram Negative ◽

Culture Positive ◽

Acute Myeloid

Abstract Introduction: The treatment of acute myeloid leukemia (AML) consists of induction therapy with anthracyclines and cytarabine followed by two to four cycles of consolidation therapy with high-dose cytarabine after achieving remission. There have been very few studies comparing infections during induction and consolidation. We have analyzed blood cultures of patients with AML during episodes of fever occurring during induction and consolidation, for comparing the bloodstream infections in both the phases. Materials and Methods: Blood cultures of patients during febrile episodes were collected from central venous catheters and peripheral blood, both during induction and consolidation therapy of AML. Results: The study population included 52 AML patients. During induction, there were 52 episodes of fever and 25 (48%) blood cultures were positive, 15 of these blood cultures reported Gram-negative organisms, 9 reported Gram-positive organisms and 1 as yeast. During consolidation, 47 episodes of fever were recorded and blood cultures were positive in 12, of which 7 were Gram-negative, 5 were Gram-positive. Conclusion: The incidence of blood culture positive infections during therapy of AML at our center was higher. The predominant organism isolated was Gram-negative both during induction and consolidation. The incidence of blood culture positive infections had decreased by 50% during consolidation.

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Pattern of bacterial isolates causing neonatal septicemia along with their pattern of antibiotic susceptibility.

The Professional Medical Journal ◽

10.29309/tpmj/2020.27.04.3524 ◽

2020 ◽

Vol 27 (04) ◽

pp. 737-741

Author(s):

Shahid Iqbal ◽

Fazal Ur Rehman ◽

Waqas Ali ◽

Sanam Bano Rajper

Keyword(s):

Blood Culture ◽

Antibiotic Susceptibility ◽

Data Entry ◽

Antibiotic Sensitivity ◽

Bacterial Isolates ◽

Candida Spp ◽

Gram Positive ◽

Neonatal Septicemia ◽

Gram Negative ◽

Empiric Antibiotic

Objectives: We planned this study to observe the pattern related to bacterial isolates causing neonatal septicemia along with their pattern of antibiotic susceptibility. Study Design: Prospective study. Setting: Department of Neonatology, Sheikh Khalifa Bin Zaid Al Nahyan Teaching Hospital, Rawlakot. Period: From 1st January 2018 to 30th June 2018. Material & Methods: Prior to empiric antibiotic usage, blood was collected from neonates having clinical sepsis and sent for blood culture. A total of 60 neonates with culture proven sepsis were enrolled for this study. Reports of blood culture were evaluated for isolates of bacteria as well as patterns of sensitivity for frequently used antibiotics in the institution. SPSS version 21.0 was used for data entry and analysis. Results: A total of 60 neonates having culture proven sepsis were enrolled in the current study. Amongst these, 39 (65.0) were male and 21 (35.0%) female. Early onset of sepsis was diagnosed in most, 42 (70.0%) neonates. Majority of neonates, 50 (83.3%) were delivered in the same hospital. Gram negative isolates were found in 43 (71.7%) and 15 (25.0%) gram positive while 2 (3.3%) candida spp. In terms of pattern of antibiotic sensitivity, 4 (9.3%) isolates of gram negative were found resistant to every antibiotic routinely used while gram positive isolates showed excellent sensitivity to vancomycin. Conclusion: Gram negative isolates of organisms were found to be the most sensitive to carbepenems (especially meropenem) as well as aminoglycosides while gram positive isolates showed excellent sensitive regarding vancomycin.

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Sepsis in cancer patients residing in Zimbabwe: Spectrum of bacterial and fungal aetiologies and their antimicrobial susceptibility patterns.

10.21203/rs.2.10948/v2 ◽

2019 ◽

Author(s):

FRANK CHINOWAITA ◽

Wendy Chaka ◽

Tinashe K Nyazika ◽

Tendai C Maboreke ◽

Emmanuel Tizauone ◽

...

Keyword(s):

Blood Culture ◽

Cancer Patients ◽

Antimicrobial Susceptibility ◽

Antimicrobial Treatment ◽

Blood Cultures ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Patients With Cancer ◽

Susceptibility Patterns

Abstract Introduction: Cancer and sepsis comorbidity is a major public health problem in most parts of the world including Zimbabwe. The microbial aetiologies of sepsis and their antibiograms vary with time and locations. Knowledge on local microbial aetiologies of sepsis and their susceptibility patterns is critical in guiding empirical antimicrobial treatment choices. Methods: This was a descriptive cross sectional study which determined the microbial aetiologies of sepsis from blood cultures of paediatric and adult cancer patients obtained between July 2016 and June 2017. The TDR-X120 blood culture system and TDR 300B auto identification machine were used for incubation of blood culture bottles and identification plus antimicrobial susceptibility testing, respectively. Clinical and laboratory standards institute (CLSI) standard breakpoints were used to interpret the antimicrobial susceptibility results. Results: A total of 142 participants were enrolled; 50 (35.2%) had positive blood cultures with 56.0% Gram positive, 42.0% Gram negative bacteria and 2.0% yeast isolates. Most common isolates were coagulase negative Staphylococcus spp. (CoNS) (22.0%), Escherichia coli (16.0%), Klebsiella pneumoniae (14.0%), Enterococcus faecalis (14.0%) and Staphylococcus aureus (8.0%) in all cancer patients. These isolates were similar in both haematological and solid cancers. Gram negative isolates exhibited high resistance to gentamicin (61.9%) and ceftriaxone (71.4%) which are the empiric antimicrobial agents used in our setting. Amikacin and meropenem showed 85.7% and 95.2% activity respectively against all Gram negative isolates while vancomycin and linezolid were effective against 96.2% and 100.0% of all Gram positive isolates respectively. Ten (66.7%) isolates of E. coli and K. pneumoniae were extended spectrum β-lactamase (ESBL) positive. Among Staphylococcus species it was also observed that 10/15 (66.7%) of the isolates were methicillin resistan t. Conclusions : The major microbial aetiologies of sepsis among patients with cancer in Zimbabwe were CoNS, E. coli , K. pneumoniae , E. faecalis and S. aureus . Most isolates were resistant to commonly used empirical antibiotics and there was high level of ESBL and methicillin resistance carriage. A nationwide survey on microbial aetiologies of sepsis and their susceptibility patterns would assist in the guidance of effective sepsis empiric antimicrobial treatment among patients with cancer.

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