ePlex Blood Culture Identification Gram Negative (BCID-GN) Panel
K213236 · Genmark Diagnostics, Incorporated · PEN · Apr 27, 2022 · Microbiology
Device Facts
| Record ID | K213236 |
| Device Name | ePlex Blood Culture Identification Gram Negative (BCID-GN) Panel |
| Applicant | Genmark Diagnostics, Incorporated |
| Product Code | PEN · Microbiology |
| Decision Date | Apr 27, 2022 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 866.3365 |
| Device Class | Class 2 |
Intended Use
The GenMark ePlex® Blood Culture Identification Gram-Negative (BCID-GN) Panel is a qualitative nucleic acid multiplex in vitro diagnostic test intended for use on GenMark's ePlex Instrument for simultaneous qualitative detection and identification of multiple potentially pathogenic gram-negative bacterial organisms and select determinants associated with antimicrobial resistance in positive blood culture. In addition, the ePlex BCID-GN Panel is capable of detecting several gram-positive bacteria (Pan Gram-Positive assay) and several Candida species (Pan Candida assay). The ePlex BCID-GN Panel is performed directly on blood culture samples identified as positive by a continuous monitoring blood culture system and which contain gram-negative organism.
Device Story
The ePlex BCID-GN Panel is an in vitro diagnostic test for identifying gram-negative bacteria and antimicrobial resistance genes in positive blood culture samples. It uses a cartridge-based system on the ePlex Instrument to perform automated nucleic acid extraction, PCR amplification, and competitive nucleic acid hybridization. The device uses a sandwich assay format where target DNA binds to solution-phase signal probes and solid-phase electrode-bound capture probes. Detection is achieved via alternating current voltammetry on a printed circuit board. The system is used in clinical laboratories by trained personnel. Results are provided to clinicians to assist in the diagnosis of bloodstream infections and to guide antimicrobial therapy. The device provides rapid identification, potentially allowing for earlier targeted treatment and improved patient outcomes.
Clinical Evidence
Clinical validation utilized a combination of 122 clinical samples and 138 contrived blood culture bottles. Performance was compared against comparator methods for clinical specimens and expected results for contrived specimens. Sensitivity/PPA and Specificity/NPA were ≥95% for all targets. Root cause analysis for isolated false positives (99.6% NPA for A. baumannii and P. mirabilis) identified workflow contamination during sample preparation/loading.
Technological Characteristics
The device utilizes competitive nucleic acid hybridization in a sandwich assay format. It performs automated nucleic acid extraction via magnetic beads, PCR/RT-PCR amplification, and electrochemical detection using ferrocene-labeled signal probes on gold electrodes. The system is a closed, cartridge-based platform. Software is embedded in the ePlex System. Sterilization is not applicable as it is a single-use cartridge system.
Indications for Use
Indicated for patients exhibiting signs/symptoms of bloodstream infection. Used for qualitative detection/identification of gram-negative bacteria, select antimicrobial resistance markers, Pan Gram-Positive bacteria, and Pan Candida species in positive blood culture samples. Results are intended to be used in conjunction with Gram stain and other clinical information; not for sole diagnosis.
Regulatory Classification
Identification
A multiplex nucleic acid assay for identification of microorganisms and resistance markers from positive blood cultures is a qualitative in vitro device intended to simultaneously detect and identify microorganism nucleic acids from blood cultures that test positive by Gram stain or other microbiological stains. The device detects specific nucleic acid sequences for microorganism identification as well as for antimicrobial resistance. This device aids in the diagnosis of bloodstream infections when used in conjunction with other clinical and laboratory findings. However, the device does not replace traditional methods for culture and susceptibility testing.
Special Controls
In combination with the general controls of the FD&C Act, the Verigene® Gram Positive Blood Culture Nucleic Acid Test is subject to the following special controls: The special controls for the BC-GP Assay are contained in the guideline document entitled "Class II Special Controls Guideline: Multiplex Nucleic Acid Assay for Identification of Microorganisms and Resistance Markers from Positive Blood Cultures."
*Classification.* Class II (special controls). The special control for this device is FDA's guideline document entitled “Class II Special Controls Guideline: Multiplex Nucleic Acid Assay for Identification of Microorganisms and Resistance Markers from Positive Blood Cultures.” For availability of the guideline document, see § 866.1(e).
Predicate Devices
- ePlex Blood Culture Identification Gram-Negative (BCID-GN) Panel (K182619)
Related Devices
- K182619 — ePlex Blood Culture Identification Gram Negative (BCID-GN) Panel · Genmark Diagnostics, Incorporated · Apr 12, 2019
- K243013 — LIAISON PLEX Gram-Negative Blood Culture Assay · Luminex Corporation · Apr 18, 2025
- K181663 — ePlex Blood Culture Identification Panel - Gram Positive (BCID-GP) Panel · Genmark Diagnostics, Incorporated · Dec 20, 2018
- K132843 — VERIGENE GRAM NEGATIVE BLOOD CULTURE NUCLEIC ACID TEST (BC-GN) · Nanosphere, Inc. · Jan 8, 2014
Submission Summary (Full Text)
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GenMark Diagnostics, Incorporated Alan Maderazo VP, Quality, Regulatory & Clinical Affairs 5964 La Place Court Carlsbad, California 92008
April 27, 2022
#### Re: K213236
Trade/Device Name: ePlex Blood Culture Identification Gram Negative (BCID-GN) Panel Regulation Number: 21 CFR 866.3365 Regulation Name: Multiplex Nucleic Acid Assay For Identification Of Microorganisms And Resistance Markers From Positive Blood Cultures Regulatory Class: Class II Product Code: PEN, PAM, PEO Dated: September 29, 2021 Received: September 30, 2021
Dear Alan Maderazo:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's
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requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Noel Gerald, Ph.D. Chief Division of Microbiology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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#### Indications for Use
510(k) Number (if known) K213236
#### Device Name
ePlex Blood Culture Identification Gram-Negative (BCID-GN) Panel
#### Indications for Use (Describe)
The GenMark ePlex® Blood Culture Identification Gram-Negative (BCID-GN) Panel is a qualitative nucleic acid multiplex in vitro diagnostic test intended for use on GenMark's ePlex Instrument for simultaneous qualitative detection and identification of multiple potentially pathogenic gram-negative bacterial organisms and select determinants associated with antimicrobial resistance in positive blood culture. In addition, the ePlex BCID-GN Panel is capable of detecting several gram-positive bacteria (Pan Gram-Positive assay) and several Candida species (Pan Candida assay). The ePlex BCID-GN Panel is performed directly on blood culture samples identified as positive by a continuous monitoring blood culture system and which contain gram-negative organism.
The following bacterial organisms and genes associated with antibiotic resistance are identified using the ePlex BCID-GN Panel: Acinetobacter baumannii, Bacteroides fragilis, Citrobacter sakazakii, Enterobacter cloacae complex, Enterobacter (non-cloacae complex), Escherichia coli, Fusobacterium necrophorum, Fusobacterium nucleatum, Haemophilus influenzae, Klebsiella oxytoca, Klebsiella pneumoniae group, Morganii, Neisseria meningitidis, Proteus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella, Serratia marcescens, Stenotrophomonas maltophilia, CTX-M (blaCTX-M), IMP (blaMP) , KPC (blaKPC) , NDM (blaNDM), OXA (blaOXA) (OXA-23 and OXA-48 groups only), and VIM (blaVIM).
The ePlex BCID-GN Panel contains assays for the detection of genetic determinants associated with resistance to antimicrobial agents including CTX-M(blaCTX-M), which is associated with resistance to extended spectrum betalactamase (ESBL)-mediated resistance to penicillins, cephalosporins, and monobactams, as well as OXA (blaOXA) (OXA-23 and OXA-48 groups only), KPC (blaKPC), and metallo-beta-lactamases IMP (blaIMP), and NDM (blaNDM), which is associated with carbapenemase-mediated resistance. The antimicrobial resistance gene detected may or may not be associated with the agent responsible for disease. Negative results for these select antimicrobial resistance assays do not indicate susceptibility, as there are multiple mechanisms of resistance in gramnegative bacteria.
The ePlex BCID-GN Panel also contains targets designed to detect a broad range of organisms with a potentially misleading Gram stain result or organisms that may be missed by Gram staining altogether, for example in the case of coinfections. These include a broad Pan Gram-Positive assay (which is designed to detect Bacillus cereus group, Bacillus subtilis group, Enterococcus, Staphylococus, and Streptococcus), as well as a Pan Candida assay, which is designed to detect four Candida species: Candida albicans, Candida krusei, and Candida parapsilosis.
The detection and identification of specific bacterial and fungal nucleic acids from individuals exhibiting signs and/or symptoms of bloodstream infection aids in the diagnosis of bloodstream infection when used in conjunction with other clinical information. The results from the ePlex BCID-GN Panel are intended to be interpreted in conjunction with Gram stain results and should not be used as the sole basis for diagnosis, treatment, or other patient management decisions.
Negative results in the setting of a suspected bloodstream infection with pathogens that are not detected by this test. Positive results do not rule out co-infection with other organisms; the organism(s) detected by the ePlex BCID-GN Panel may not be the definite cause of disease. Additional laboratory testing (e.g. sub-culturing of positive blood cultures for identification of organisms not detected by ePlex BCID-GN Panel and for susceptibility testing, differentiation of mixed growth, and association of antimicrobial resistance marker genes to a specific organism) and clinical presentation must be taken into consideration in the final diagnosis of bloodstream infection.
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Type of Use (Select one or both, as applicable)
X Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)
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#### 5.0 510(k) Summary
The 510(k) Summary was updated to align with the most current revision of the package insert, which incorporates changes in the Limit of Detection (LoD) section based on the results from studies conducted to support implementation of a design change (i.e., addition of oligonucleotides to improve robustness and inclusivity of the E.coli, Citrobacter, Enterococcus, and P. aeruginosa assays). The addition of oligonucleotides to specific PCR reactions introduces performance risks to the resident assays contained in those affected PCR reactions. As a result, the following studies were conducted to mitigate the identified risks to product performance.
- 1. Evaluation of overall BCID-GN Panel Performance: this study utilized a multianalyte test mix (containing a representative analyte from each of the eight multiplex PCR pools) to systematically assess overall performance of the BCID-GN Panel. This design was utilized to ensure that the proposed change does not introduce any unexpected issues that result in a systematic assay failure.
- 2. LoD Verification Study: this study verified that the LoDs of the targets affected by the change are not adversely impacted. These results demonstrate that the analytical sensitivity of the test remains equivalent.
- 3. Clinical Sample Evaluation: this study utilized characterized clinical samples to verify that the proposed change does not adversely impact clinical performance.
All studies met the predetermined acceptance criteria demonstrating no adverse impact to the BCID-GN Panel performance, which supports implementation of the proposed change.
The changes to the 510(k) Summary include identification of the following strains (in Table 56 of the 510(k) Summary) that were tested as part of the LoD verification study:
- H. influenzae (ATCC33930) .
- . N. meningitidis (NCTC10026)
- E. coli (JHU01-D80401147) .
- . P. aeruginosa (SDx071)
All other information in the 510(k) Summary are unchanged.
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#### 510(k) Summary
Summary of Safety and Effectiveness
## Submitter Information
| Submitter: | GenMark Diagnostics, Incorporated<br>5964 La Place Court<br>Carlsbad, CA 92008 |
|------------------------------------|---------------------------------------------------------------------------------------|
| Manufacturer: | GenMark Diagnostics, Incorporated<br>5964 La Place Court<br>Carlsbad, CA 92008 |
| Establishment Registration Number: | 3008632402 |
| Contact: | Alan Maderazo, Ph.D., RAC<br>Vice President, Quality, Regulatory and Clinical Affairs |
| Phone: | 760-448-4308 |
| Fax: | 760-683-6961 |
| E-mail: | Al.Maderazo@genmarkdx.com |
| Alternate Contact: | Beth Stofka<br>Sr. Regulatory Affairs Specialist |
| Phone: | 760-579-4778 |
| Fax: | 760-683-6961 |
| E-mail: | Beth.Stofka@genmarkdx.com |
| Date Prepared: | April 4, 2022 |
## Name of Device and Classification
| Product Name: | ePlex® Blood Culture Identification Gram-Negative (BCID-GN) Panel |
|------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------|
| Device Classification: | 866.3980, Multiplex nucleic acid assay for identification of<br>microorganisms and resistance markers from positive blood cultures,<br>Class II |
| Product Code(s): | PEN, PAM, PEO |
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#### Predicate Device
Predicate: The ePlex Blood Culture Identification Gram-Negative (BCID-GN) Panel; GenMark Diagnostics, Inc .; K182619
#### Device Description
The ePlex Blood Culture Identification Gram-Negative (BCID-GN) Panel is based on the principles of competitive nucleic acid hybridization using a sandwich assay format, wherein a single-stranded target binds concurrently to a sequence-specific solution-phase signal probe and a solid-phase electrode-bound capture probe. The test employs nucleic acid extraction, target amplification via polymerase chain reaction (PCR) or reverse transcription PCR (RT-PCR) and hybridization of target DNA. In the process, the double-stranded PCR amplicons are digested with exonuclease to generate single-stranded DNA suitable for hybridization.
Nucleic acid extraction from biological samples occurs within the cartridge via cell lysis, nucleic acid capture onto magnetic beads, and release for amplification. The nucleic acid extraction is processed through microfluidic liquid handling. Once the nucleic acid targets are captured and inhibitors are washed away, the magnetic particles are delivered to the electrowetting environment on the printed circuit board (PCB) and the targets are eluted from the particles and amplified.
During hybridization, the single-stranded target DNA binds to a complementary, single-stranded capture probe immobilized on the working gold electrode surface. Single-stranded signal probes (labeled with electrochemically active ferrocenes) bind to specific target sequence / region adjacent to the capture probe. Simultaneous hybridization of target to signal probes and capture probe is detected by alternating current voltammetry (ACV). Each working electrode on the array contains specific capture probes, and sequential analysis of each electrode allows detection of multiple analyte targets.
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#### Intended Use/Indications for Use
The GenMark ePlex® Blood Culture Identification Gram-Negative (BCID-GN) Panel is a qualitative nucleic acid multiplex in vitro diagnostic test intended for use on GenMark's ePlex Instrument for simultaneous qualitative detection and identification of multiple potentially pathogenic gram-negative bacterial organisms and select determinants associated with antimicrobial resistance in positive blood culture. In addition, the ePlex BCID-GN Panel is capable of detecting several gram-positive bacteria (Pan Gram-Positive assay) and several Candida species (Pan Candida assay). The ePlex BCID-GN Panel is performed directly on blood culture samples identified as positive by a continuous monitoring blood culture system and which contain gram-negative organism.
The following bacterial organisms and genes associated with antibiotic resistance are identified using the ePlex BCID-GN Panel: Acinetobacter baumannii, Bacteroides fragilis, Citrobacter, Cronobacter sakazakii, Enterobacter cloacae complex, Enterobacter (non-cloacae complex), Escherichia coli, Fusobacterium necrophorum, Fusobacterium nucleatum, Haemophilus influenzae, Klebsiella oxvtoca, Klebsiella pneumoniae group, Morganella morganii, Neisseria meningitidis, Proteus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella, Serratia, Serratia marcescens, Stenotrophomonas maltophilia, СТХ-М (blacтх-м), IMP (blaмг) , КРС (blakec) , NDM (bland), OXA (blaoxa) (OXA-23 and OXA-48 groups only), and VIM (blavim).
The ePlex BCID-GN Panel contains assays for the detection of genetic determinants associated with resistance to antimicrobial agents including CTX-M(blacrx-M), which is associated with resistance to extended spectrum beta-lactamase (ESBL)-mediated resistance to penicillins, cephalosporins and monobactams, as well as OXA (blaoxA) (OXA-23 and OXA-48 groups only), KPC (blakec), and metallo-beta-lactamases IMP (blanм), VIM (blaviм), and NDM (blandM), which is associated with carbapenemase-mediated resistance. The antimicrobial resistance gene detected may or may not be associated with the agent responsible for disease. Negative results for these select antimicrobial resistance assays do not indicate susceptibility, as there are multiple mechanisms of resistance in gram-negative bacteria.
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The ePlex BCID-GN Panel also contains targets designed to detect a broad range of organisms with a potentially misleading Gram stain result or organisms that may be missed by Gram staining altogether, for example in the case of co-infections. These include a broad Pan Gram-Positive assay (which is designed to detect Bacillus cereus group, Bacillus subtilis group, Enterococcus, Staphylococcus, and Streptococcus), as well as a Pan Candida assay, which is designed to detect four Candida species: Candida albicans, Candida glabrata, Candida krusei, and Candida parapsilosis.
The detection and identification of specific bacterial and fungal nucleic acids from individuals exhibiting signs and/or symptoms of bloodstream infection aids in the diagnosis of bloodstream infection when used in conjunction with other clinical information. The results from the ePlex BCID-GN Panel are intended to be interpreted in conjunction with Gram stain results and should not be used as the sole basis for diagnosis, treatment, or other patient management decisions.
Negative results in the setting of a suspected bloodstream infection may be due to infection with pathogens that are not detected by this test. Positive results do not rule out co-infection with other organisms; the organism(s) detected by the ePlex BCID-GN Panel may not be the definite cause of disease. Additional laboratory testing (e.g. sub-culturing of positive blood cultures for identification of organisms not detected by ePlex BCID-GN Panel and for susceptibility testing, differentiation of mixed growth, and association of antimicrobial resistance marker genes to a specific organism) and clinical presentation must be taken into consideration in the final diagnosis of bloodstream infection.
#### Summary of Technological Characteristics of the Device Compared to the Predicate Device
The updated GenMark ePlex Blood Culture Identification Gram-Negative (BCID-GN) Panel (identified as the "SubjectDevice") and the legally marketed device, the original GenMark ePlex BCID-GN Panel (K182619) (identified as the "Predicate Device") are described below:
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| Characteristic | Predicate Device (K182619) | Subject Device (Updated) |
|---------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Product Name | ePlex BCID-GN Panel | Same |
| Manufacturer | GenMark Diagnostics, Inc. | Same |
| Organisms<br>Detected | Acinetobacter baumannii Bacteroides fragilis Citrobacter Cronobacter sakazakii Enterobacter cloacae complex Enterobacter (non-cloacae complex) Escherichia coli Fusobacterium necrophorum Fusobacterium nucleatum Haemophilus influenzae Klebsiella oxytoca Klebsiella pneumoniae Morganella morganii Neisseria meningitidis Proteus Proteus mirabilis Pseudomonas aeruginosa Salmonella Serratia Serratia marcescens Stenotrophomonas Saltophiliapyogenes (GAS) | Same<br>Additional strains were tested as part of the Limit of Detection (LoD) study which include the following: H. influenzae (ATCC33930) N. meningitidis (NCTC10026) E. coli (JHU01-D80401147) P. aeruginosa (SDx071) |
| Resistance Genes<br>Detected | CTX-M, IMP, KPC, NDM, OXA, andVIM | Same |
| Indication for<br>Use | The ePlex BCID-GN Panel is indicated as an aid in the diagnosis of specific agents of bacteremia. The use of additional laboratory testing (e.g. sub- culturing of positive blood cultures for identification of organisms not detected by the ePlex BCID-GN Panel and for susceptibility testing, differentiation of mixed growth, and association of antimicrobial resistance marker genes toa specific organism) and clinical presentation must be taken into consideration in the final diagnosis of blood stream infection. | Same |
| Specimen Type | Blood culture samples identified as positive by a continuous monitoringblood culture system that demonstrates the presence of organisms as confirmed by Gram stain. | Same |
| Characteristic | Predicate Device (K182619) | Subject Device (Updated) |
| Chemistry | Reagents on cartridge include: sample<br>lysis and nucleic acid extraction, PCR<br>amplification and hybridization-based<br>electrochemical detection reagents. | Same |
| Hardware | GenMark ePlex Instrument & SingleUse<br>Cartridge | Same |
| SoftwareInterface<br>Result Reporting | GenMark ePlex System Software GenMark ePlex BCID-GN Panel<br>Software | Same |
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Analysis of the similarities and differences indicate that the devices are substantially equivalent in their intended uses/indications for use, and are generally the same regarding user process, ease of use and general operator protocol. Comparison of technological similarities and differences between the proposed device and the predicate do not raise new or different questions of safety and effectiveness, and therefore render the proposed device as substantially equivalent to the predicate device.
#### Summary of Performance Data
#### Expected Values
A prospective, multicenter clinical study was conducted to evaluate the clinical performance of the ePlex BCID-GN Panel in positive blood culture samples. A total of 349 samples were prospectively collected at 7 clinical sites in 2 phases from patients of all ages and genders. In the first phase from June 2014 through July 2016, 182 samples were prospectively collected and frozen; from June through July 2018, 167 samples were prospectively collected and tested fresh (never frozen). The expected values of individual analytes based on the ePlex BCID-GN Panel results in prospective samples are summarized by age group and by site in Tables 1 and 2 below.
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# Table 1: Expected Value by Age Group (Prospective Samples)
| Target | All Ages<br>(N=349)<br>n (%) | Age <1<br>(N=7)<br>n (%) | Age 1-17<br>(N=10)<br>n (%) | Age 18-44<br>(N=50)<br>n (%) | Age 45-64<br>(N=124)<br>n (%) | Age 65-84<br>(N=125)<br>n (%) | Age 85+<br>(N=33)<br>n (%) | Target | All Sites<br>(N=349)<br>n (%) | Site 1<br>(N=88)<br>n (%) | Site 2<br>(N=23)<br>n (%) | Site 3<br>(N=98)<br>n (%) | Site 4<br>(N=58)<br>n (%) | Site 5<br>(N=46)<br>n (%) | Site 6<br>(N=28)<br>n (%) | Site 7<br>(N=8)<br>n (%) |
|---------------------------------------|------------------------------|--------------------------|-----------------------------|------------------------------|-------------------------------|-------------------------------|----------------------------|------------------------------|-------------------------------|---------------------------|---------------------------|---------------------------|---------------------------|---------------------------|---------------------------|--------------------------|
| Acinetobacter baumannii | 4 (1.1) | 0 (0.0) | 0 (0.0) | 1 (2.0) | 2 (1.6) | 1 (0.8) | 0 (0.0) | Acinetobacter baumannii | 4 (1.1) | 3 (3.4) | 0 (0.0) | 1 (1.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Bacteroides fragilis | 11 (3.2) | 0 (0.0) | 0 (0.0) | 2 (4.0) | 4 (3.2) | 2 (1.6) | 3 (9.1) | Bacteroides fragilis | 11 (3.2) | 2 (2.3) | 3 (13.0) | 3 (3.1) | 2 (3.4) | 1 (2.2) | 0 (0.0) | 0 (0.0) |
| Citrobacter | 8 (2.3) | 0 (0.0) | 0 (0.0) | 2 (4.0) | 1 (0.8) | 2 (1.6) | 3 (9.1) | Citrobacter | 8 (2.3) | 2 (2.3) | 0 (0.0) | 3 (3.1) | 1 (1.7) | 1 (2.2) | 1 (3.6) | 0 (0.0) |
| Cronobacter sakazakii | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | Cronobacter sakazakii | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Enterobacter (non-cloacae<br>complex) | 9 (2.6) | 0 (0.0) | 1 (10.0) | 2 (4.0) | 5 (4.0) | 1 (0.8) | 0 (0.0) | Enterobacter | 9 (2.6) | 2 (2.3) | 0 (0.0) | 4 (4.1) | 0 (0.0) | 1 (2.2) | 2 (7.1) | 0 (0.0) |
| Enterobacter cloacae complex | 23 (6.6) | 3 (42.9) | 1 (10.0) | 6 (12.0) | 5 (4.0) | 8 (6.4) | 0 (0.0) | (non-cloacae complex) | | | | | | | | |
| Escherichia coli | 132 (37.8) | 2 (28.6) | 2 (20.0) | 16 (32.0) | 41 (33.1) | 55 (44.0) | 16 (48.5) | Enterobacter cloacae complex | 23 (6.6) | 3 (3.4) | 1 (4.3) | 10 (10.2) | 1 (1.7) | 6 (13.0) | 2 (7.1) | 0 (0.0) |
| Fusobacterium necrophorum | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | Escherichia coli | 132 (37.8) | 30 (34.1) | 8 (34.8) | 37 (37.8) | 25 (43.1) | 17 (37.0) | 12 (42.9) | 3 (37.5) |
| Fusobacterium nucleatum | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | Fusobacterium necrophorum | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Haemophilus influenzae | 7 (2.0) | 0 (0.0) | 0 (0.0) | 3 (6.0) | 1 (0.8) | 1 (0.8) | 2 (6.1) | Fusobacterium nucleatum | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Klebsiella oxytoca | 12 (3.4) | 0 (0.0) | 0 (0.0) | 3 (6.0) | 8 (6.5) | 1 (0.8) | 0 (0.0) | Haemophilus influenzae | 7 (2.0) | 1 (1.1) | 0 (0.0) | 2 (2.0) | 2 (3.4) | 1 (2.2) | 1 (3.6) | 0 (0.0) |
| Klebsiella pneumoniae group | 59 (16.9) | 1 (14.3) | 1 (10.0) | 10 (20.0) | 26 (21.0) | 17 (13.6) | 4 (12.1) | Klebsiella oxytoca | 12 (3.4) | 5 (5.7) | 0 (0.0) | 3 (3.1) | 1 (1.7) | 2 (4.3) | 1 (3.6) | 0 (0.0) |
| Morganella morganii | 3 (0.9) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (1.6) | 1 (0.8) | 0 (0.0) | Klebsiella pneumoniae group | 59 (16.9) | 17 (19.3) | 3 (13.0) | 20 (20.4) | 5 (8.6) | 7 (15.2) | 4 (14.3) | 3 (37.5) |
| Neisseria meningitidis | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | Morganella morganii | 3 (0.9) | 0 (0.0) | 1 (4.3) | 2 (2.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Proteus | 22 (6.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 6 (4.8) | 13 (10.4) | 3 (9.1) | Neisseria meningitidis | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Proteus mirabilis | 22 (6.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 6 (4.8) | 13 (10.4) | 3 (9.1) | Proteus | 22 (6.3) | 9 (10.2) | 0 (0.0) | 5 (5.1) | 5 (8.6) | 2 (4.3) | 1 (3.6) | 0 (0.0) |
| Pseudomonas aeruginosa | 28 (8.0) | 0 (0.0) | 2 (20.0) | 3 (6.0) | 12 (9.7) | 10 (8.0) | 1 (3.0) | Proteus mirabilis | 22 (6.3) | 9 (10.2) | 0 (0.0) | 5 (5.1) | 5 (8.6) | 2 (4.3) | 1 (3.6) | 0 (0.0) |
| Salmonella | 2 (0.6) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.8) | 1 (0.8) | 0 (0.0) | Pseudomonas aeruginosa | 28 (8.0) | 5 (5.7) | 2 (8.7) | 10 (10.2) | 8 (13.8) | 2 (4.3) | 1 (3.6) | 0 (0.0) |
| Serratia | 10 (2.9) | 0 (0.0) | 1 (10.0) | 0 (0.0) | 5 (4.0) | 4 (3.2) | 0 (0.0) | Salmonella | 2 (0.6) | 1 (1.1) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (2.2) | 0 (0.0) | 0 (0.0) |
| Serratia marcescens | 9 (2.6) | 0 (0.0) | 1 (10.0) | 0 (0.0) | 4 (3.2) | 4 (3.2) | 0 (0.0) | Serratia | 10 (2.9) | 1 (1.1) | 2 (8.7) | 1 (1.0) | 3 (5.2) | 3 (6.5) | 0 (0.0) | 0 (0.0) |
| Stenotrophomonas maltophilia | 3 (0.9) | 0 (0.0) | 0 (0.0) | 3 (6.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | Serratia marcescens | 9 (2.6) | 1 (1.1) | 2 (8.7) | 1 (1.0) | 3 (5.2) | 2 (4.3) | 0 (0.0) | 0 (0.0) |
| Pan Candida | 2 (0.6) | 1 (14.3) | 0 (0.0) | 0 (0.0) | 1 (0.8) | 0 (0.0) | 0 (0.0) | Stenotrophomonas maltophilia | 3 (0.9) | 1 (1.1) | 0 (0.0) | 0 (0.0) | 1 (1.7) | 0 (0.0) | 1 (3.6) | 0 (0.0) |
| Pan Gram-Positive | 24 (6.9) | 1 (14.3) | 2 (20.0) | 5 (10.0) | 7 (5.6) | 7 (5.6) | 2 (6.1) | Pan Candida | 2 (0.6) | 0 (0.0) | 0 (0.0) | 1 (1.0) | 0 (0.0) | 0 (0.0) | 1 (3.6) | 0 (0.0) |
| CTX-M | 24 (6.9) | 0 (0.0) | 0 (0.0) | 2 (4.0) | 7 (5.6) | 12 (9.6) | 3 (9.1) | Pan Gram-Positive | 24 (6.9) | 15 (17.0) | 1 (4.3) | 5 (5.1) | 1 (1.7) | 0 (0.0) | 2 (7.1) | 0 (0.0) |
| IMP | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | CTX-M | 24 (6.9) | 9 (10.2) | 1 (4.3) | 3 (3.1) | 4 (6.9) | 5 (10.9) | 2 (7.1) | 0 (0.0) |
| KPC | 3 (0.9) | 0 (0.0) | 0 (0.0) | 1 (2.0) | 1 (0.8) | 1 (0.8) | 0 (0.0) | IMP | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| NDM | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | KPC | 3 (0.9) | 1 (1.1) | 0 (0.0) | 1 (1.0) | 1 (1.7) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| OXA | 1 (0.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.8) | 0 (0.0) | 0 (0.0) | NDM | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| VIM | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | OXA | 1 (0.3) | 1 (1.1) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| VIM | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | | | | | | | | |
{12}------------------------------------------------
# Table 2: Expected Value by Collection Site (Prospective Samples)
{13}------------------------------------------------
#### PERFORMANCE CHARACTERISTICS
#### Clinical Performance
Samples with final, valid ePlex BCID-GN Panel test results and a valid comparator result were evaluable and included in summaries and analyses of demographics, expected values (positivity rate), and performance characteristics. Evaluable samples included 167 prospective fresh and 182 prospective frozen samples as well as 577 retrospective samples and 777 contrived samples.
#### Comparator Method
The performance of the ePlex BCID-GN Panel was compared to standard laboratory procedures for identification of blood culture isolates, including traditional and automated identification methods, MALDI-TOF IVD, and microbiological and biochemical techniques. Identification for samples with Acinetobacter baumannii or Candida parapsilosis identified by standard laboratory procedures was confirmed using analytically validated PCR assays followed by bi-directional sequencing. For antibiotic resistance genes, the ePlex BCID-GN Panel was compared to analytically validated qPCR amplification assays followed by bi-directional sequencing in samples with an associated organism identified by culture (See Table 3 for organism associations).
| | Resistance Gene | | | | | |
|------------------------------------|-----------------|-----|-----|-----|-----|-----|
| Organism | CTX-M | IMP | KPC | NDM | OXA | VIM |
| Acinetobacter baumannii | X | X | X | X | X | X |
| Bacteroides fragilis | | | | | | |
| Citrobacter | X | X | X | X | X | X |
| Cronobacter sakazakii | | | X | | | |
| Enterobacter cloacae complex | X | X | X | X | X | X |
| Enterobacter (non-cloacae complex) | X | X | X | X | X | X |
| Escherichia coli | X | X | X | X | X | X |
| Fusobacterium necrophorum | | | | | | |
| Fusobacterium nucleatum | | | | | | |
| Haemophilus influenzae | | | | | | |
| Klebsiella oxytoca | X | X | X | X | X | X |
| Klebsiella pneumoniae | X | X | X | X | X | X |
| Morganella morganii | X | X | X | X | X | X |
| Neisseria meningitidis | | | | | | |
| Proteus | X | X | X | X | X | X |
| Proteus mirabilis | X | X | X | X | X | X |
| Pseudomonas aeruginosa | X | X | X | X | X | X |
| Salmonella | X | X | X | X | X | X |
| Serratia | X | X | X | X | X | X |
| Serratia marcescens | X | X | X | X | X | X |
| Stenotrophomonas maltophilia | X | | | | | |
#### Table 3: Resistance Marker Organism Associations
VOL 005 Page 10
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The comparator method(s) results were used to determine the Detected / Not Detected status for each target organism on the ePlex BCID-GN Panel. The comparator methods for each target are summarized in Table 4.
| Target | Comparator Method |
|----------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Acinetobacter baumannii | Standard laboratory procedures for organism ID.<br>PCR/sequencing to confirm Acinetobacter baumannii or different<br>Acinetobacter species not included in this panel. |
| Bacteroides fragilis | |
| Citrobacter | |
| Cronobacter sakazakii | |
| Enterobacter cloacae complex | |
| Enterobacter non-cloacae complex | |
| Escherichia coli | |
| Fusobacterium necrophorum | |
| Fusobacterium nucleatum | |
| Haemophilus influenzae | |
| Klebsiella oxytoca | |
| Klebsiella pneumoniae | Standard laboratory procedures for organism identification. |
| Morganella morganii | |
| Neisseria meningitidis | |
| Proteus | |
| Proteus mirabilis | |
| Pseudomonas aeruginosa | |
| Salmonella | |
| Serratia | |
| Serratia marcescens | |
| Stenotrophomonas maltophilia | |
| Pan Gram-Negative | |
| Pan Candida | Standard laboratory procedures for organism ID.<br>PCR/sequencing to confirm C. parapsilosis or identify<br>C. metapsilosis, C. orthopsilosis. |
| CTX-M, IMP, KPC, NDM, OXA, VIM | qPCR/sequencing in samples with associated organism detected<br>by comparator method. See Table 3 for organism associations. |
Table 4: Comparator Method(s) by ePlex BCID-GN Panel Target
{15}------------------------------------------------
#### Demographics of Clinical Samples
Clinical performance was evaluated in positive blood culture samples prospectively and retrospectively collected. Prospective samples were collected at 7 clinical sites in 2 phases. From June 2014 through July 2016, 183 samples were prospectively collected and frozen; from June through July 2018, 171 samples were prospectively collected and tested fresh (never frozen) for a total of 354 samples across the 2 phases. One of these samples was withdrawn due to organism identification from unacceptable methods. Of the 353 prospectively-collected samples eligible for testing, 349 were evaluable. Samples with final, valid ePlex BCID-GN Panel results and a valid comparator result were evaluable. Four samples were not evaluable because they did not have final, valid ePlex BCID-GN Panel results and were excluded from performance evaluations. Demographic information for prospectively-collected samples is described in Table 5. Subjects enrolled in this study were from a diverse demographic distribution and represent the intended patient population.
To supplement the number of positives for low prevalence targets in the prospective collection, 578 samples were collected retrospectively, 577 were evaluable. One sample was not evaluable because it did not have a final, valid ePlex BCID-GN Panel result and was excluded from performance evaluations. Demographic information for retrospectively-collected samples is described in Table 6.
| | All Sites<br>N = 349<br>n (%) | Site 1<br>N = 88<br>n (%) | Site 2<br>N = 23<br>n (%) | Site 3<br>N = 98<br>n (%) | Site 4<br>N = 58<br>n (%) | Site 5<br>N = 46<br>n (%) | Site 6<br>N = 28<br>n (%) | Site 7<br>N = 8<br>n (%) |
|-----------|-------------------------------|---------------------------|---------------------------|---------------------------|---------------------------|---------------------------|---------------------------|--------------------------|
| Sex | | | | | | | | |
| Male | 168 (48.1) | 37 (42.0) | 12 (52.2) | 52 (53.1) | 28 (48.3) | 21 (45.7) | 13 (46.4) | 5 (62.5) |
| Female | 181 (51.9) | 51 (58.0) | 11 (47.8) | 46 (46.9) | 30 (51.7) | 25 (54.3) | 15 (53.6) | 3 (37.5) |
| Age | | | | | | | | |
| <1 yr | 7 (2.0) | 2 (2.3) | 0 (0.0) | 4 (4.1) | 0 (0.0) | 1 (2.2) | 0 (0.0) | 0 (0.0) |
| 1-17 yrs | 10 (2.9) | 4 (4.5) | 1 (4.3) | 3 (3.1) | 1 (1.7) | 1 (2.2) | 0 (0.0) | 0 (0.0) |
| 18-44 yrs | 50 (14.3) | 10 (11.4) | 3 (13.0) | 20 (20.4) | 3 (5.2) | 8 (17.4) | 6 (21.4) | 0 (0.0) |
| 45-64 yrs | 124 (35.5) | 35 (39.8) | 9 (39.1) | 28 (28.6) | 21 (36.2) | 14 (30.4) | 13 (46.4) | 4 (50.0) |
| 65-84 yrs | 125 (35.8) | 29 (33.0) | 8 (34.8) | 35 (35.7) | 25 (43.1) | 17 (37.0) | 7 (25.0) | 4 (50.0) |
| 85+ yrs | 33 (9.5) | 8 (9.1) | 2 (8.7) | 8 (8.2) | 8 (13.8) | 5 (10.9) | 2 (7.1) | 0 (0.0) |
Table 5: Demographic Data for Clinical Samples by Collection Site (Prospective Collection)
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| | All Sites<br>N = 577<br>n (%) | Site 1<br>N = 78<br>n (%) | Site 2<br>N = 73<br>n (%) | Site 3<br>N = 31<br>n (%) | Site 4<br>N = 93<br>n (%) | Site 5<br>N=1<br>n (%) | Site 6<br>N = 80<br>n (%) | Site 7<br>N = 67<br>n (%) | Site 8<br>N = 48<br>n (%) | Site 9<br>N = 29<br>n (%) | Site 10<br>N = 77<br>n (%) |
|-----------|-------------------------------|---------------------------|---------------------------|---------------------------|---------------------------|------------------------|---------------------------|---------------------------|---------------------------|---------------------------|----------------------------|
| Sex | | | | | | | | | | | |
| Male | 307 (53.2) | 36 (46.2) | 41 (56.2) | 15 (48.4) | 49 (52.7) | 0 (0.0) | 47 (58.8) | 38 (56.7) | 29 (60.4) | 19 (65.5) | 33 (42.9) |
| Female | 270 (46.8) | 42 (53.8) | 32 (43.8) | 16 (51.6) | 44 (47.3) | 1 (100) | 33 (41.3) | 29 (43.3) | 19 (39.6) | 10 (34.5) | 44 (57.1) |
| Age | | | | | | | | | | | |
| <1 yr | 9 (1.6) | 1 (1.3) | 0 (0.0) | 0 (0.0) | 3 (3.2) | 0 (0.0) | 2 (2.5) | 0 (0.0) | 1 (2.1) | 0 (0.0) | 2 (2.6) |
| 1-17 yrs | 20 (3.5) | 1 (1.3) | 0 (0.0) | 1 (3.2) | 8 (8.6) | 0 (0.0) | 6 (7.5) | 0 (0.0) | 0 (0.0) | 1 (3.4) | 3 (3.9) |
| 18-44 yrs | 78 (13.5) | 13 (16.7) | 7 (9.6) | 2 (6.5) | 10 (10.8) | 1 (100) | 15 (18.8) | 8 (11.9) | 8 (16.7) | 6(20.7) | 8 (10.4) |
| 45-64 yrs | 193 (33.4) | 27 (34.6) | 18 (24.7) | 13 (41.9) | 27 (29.0) | 0 (0.0) | 32 (40.0) | 27 (40.3) | 16 (33.3) | 9 (31.0) | 24 (31.2) |
| 65-84 yrs | 226 (39.2) | 29 (37.2) | 40 (54.8) | 11 (35.5) | 40 (43.0) | 0 (0.0) | 20 (25.0) | 24 (35.8) | 21 (43.8) | 11 (37.9) | 30 (39.0) |
| 85+ yrs | 49 (8.5) | 7 (9.0) | 8 (11.0) | 4 (12.9) | 5 (5.4) | 0 (0.0) | 5 (6.3) | 6 (9.0) | 2 (4.2) | 2 (6.9) | 10 (13.0) |
| Unknown | 2 (0.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (3.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
Table 6: Demographic Data for Clinical Samples by Collection Site (Retrospective Collection)
#### Clinical Performance
Sensitivity or positive percent agreement (PPA) was calculated by dividing the number of true positive (TP) results by the sum of TP and false negative (FN) results, while specificity or negative percent agreement (NPA) was calculated by dividing the number of true negative (TN) results by the sum of TN and false positive (FP) result being defined as a sample where the detected ePlex BCID-GN Panel result matched the detected comparator method result, while a TN result was one where a negative ePlex BCID-GN Panel result matched a negative comparator method result. The two-sided 95% confidence interval was also calculated.
A total of 349 prospectively-collected samples (167 tested fresh and 182 tested after previously frozen) and 577 retrospectively collected samples from blood culture bottles flagged positive in a continuously monitoring blood culture system and removed from the system within 8 hours of positivity were evaluated for the ePlex BCID-GN Panel targets. Specimens evaluated were determined to contain gram-negative or gram-variable organisms based on Gram stain. A total of 777 contrived samples were prepared by spiking an isolate into a blood culture bottle with human whole blood and growing until flagged positive by a continuously monitoring blood culture system. Contrived samples were removed from the system within 8 hours of positivity and stored frozen until the time of testing. PPA and NPA results are summarized by target in Tables 7-34 below, and the strains used to contrive samples are summarized in Table 35.
{17}------------------------------------------------
| Target | Sample Type | TP/TP+FN | Sensitivity/PPA<br>% (95% CI) | TN/TN+FP | Specificity/NPA<br>% (95% CI) |
|----------------------------|-----------------------------|----------|-------------------------------|-----------|-------------------------------|
| Acinetobacter<br>baumannii | Prospective (Fresh) | 0/0 | --- | 167/167 | 100 (97.8-100) |
| | Prospective (Frozen) | 4/4 | 100 (51.0-100) | 178/178 | 100 (97.9-100) |
| | Prospective (All) | 4/4 | 100 (51.0-100) | 345/345 | 100 (98.9-100) |
| | Retrospective | 15/15 | 100 (79.6-100) | 560/561 | 99.8 (99.0-100) |
| | Prospective / Retrospective | 19/19 | 100 (83.2-100) | 905/906A | 99.9 (99.4-100) |
| | Contrived | 55/55 | 100 (93.5-100) | 722/722 | 100 (99.5-100) |
| | Overall | 74/74 | 100 (95.1-100) | 1627/1628 | 99.9 (99.7-100) |
#### Table7: Clinical Performance for Acinetobacter baumannii
CI= Confidence Interval
Acinetobacter baumanii was detected in the 1/1 false positive sample using PCR/sequencing. A.
#### Table 8: Clinical Performance for Bacteroides fragilis
| Target | Sample Type | | Sensitivity/PPA | Specificity/NPA | |
|----------------------|-----------------------------|----------|------------------|-----------------|------------------|
| | | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) |
| Bacteroides fragilis | Prospective (Fresh) | 6/6 | 100 (61.0-100) | 161/161 | 100 (97.7-100) |
| | Prospective (Frozen) | 5/5 | 100 (56.6-100) | 177/177 | 100 (97.9-100) |
| | Prospective (All) | 11/11 | 100 (74.1-100) | 338/338 | 100 (98.9-100) |
| | Retrospective | 14/17 | 82.4 (59.0-93.8) | 558/560 | 99.6 (98.7-99.9) |
| | Prospective / Retrospective | 25/28A | 89.3 (72.8-96.3) | 896/898B | 99.8 (99.2-99.9) |
| | Contrived | 40/40 | 100 (91.2-100) | 737/737 | 100 (99.5-100) |
| | Overall | 65/68 | 95.6 (87.8-98.5) | 1633/1635 | 99.9 (99.6-100) |
A. B. fragilis was not detected in 2 false negative samples, but PCR/sequencing instead detected B. caccae and B. theraiotaomicron, which were not identified by standard laboratory procedures.
B. B. fragilis was detected in 2/2 false positive samples using PCR/sequencing.
{18}------------------------------------------------
| Target | Sample Type | Sensitivity/PPA | | Specificity/NPA | |
|-------------|-----------------------------|-----------------|------------------|-----------------|------------------|
| | | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) |
| Citrobacter | Prospective (Fresh) | 3/3 | 100 (43.9-100) | 163/164 | 99.4 (96.6-99.9) |
| | Prospective (Frozen) | 2/2 | 100 (34.2-100) | 178/180 | 98.9 (96.0-99.7) |
| | Prospective (All) | 5/5 | 100 (56.6-100) | 341/344 | 99.1 (97.5-99.7) |
| | Retrospective | 20/21 | 95.2 (77.3-99.2) | 555/556 | 99.8 (99.0-100) |
| | Prospective / Retrospective | 25/26 | 96.2 (81.1-99.3) | 896/900A | 99.6 (98.9-99.8) |
| | Contrived | 43/43 | 100 (91.8-100) | 734/734 | 100 (99.5-100) |
| | Overall | 68/69 | 98.6 (92.2-99.7) | 1630/1634 | 99.8 (99.4-99.9) |
#### Table 9: Clinical Performance for Citrobacter
A. Citrobacter braakii (2) and Citrobacter freundii (2) were detected in 4/4 false positive samples using PCR/sequencing.
#### Table 10: Clinical Performance for Cronobacter sakazakii
| Target | Sample Type | Sensitivity/PPA | | Specificity/NPA | |
|-----------------------|-----------------------------|-----------------|----------------|-----------------|----------------|
| | | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) |
| Cronobacter sakazakii | Prospective (Fresh) | 0/0 | --- | 167/167 | 100 (97.8-100) |
| | Prospective (Frozen) | 0/0 | --- | 182/182 | 100 (97.9-100) |
| | Prospective (All) | 0/0 | --- | 349/349 | 100 (98.9-100) |
| | Retrospective | 1/1 | 100 (20.7-100) | 576/576 | 100 (99.3-100) |
| | Prospective / Retrospective | 1/1 | 100 (20.7-100) | 925/925 | 100 (99.6-100) |
| | Contrived | 45/45 | 100 (92.1-100) | 732/732 | 100 (99.5-100) |
| | Overall | 46/46 | 100 (92.3-100) | 1657/1657 | 100 (99.8-100) |
{19}------------------------------------------------
| Target | Sample Type | Sensitivity/PPA | | Specificity/NPA | |
|---------------------------------|-----------------------------|-----------------|------------------|-----------------|------------------|
| | | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) |
| Enterobacter cloacae<br>complex | Prospective (Fresh) | 12/12 | 100 (75.8-100) | 153/155 | 98.7 (95.4-99.6) |
| | Prospective (Frozen) | 7/7 | 100 (64.6-100) | 173/175 | 98.9 (95.9-99.7) |
| | Prospective (All) | 19/19 | 100 (83.2-100) | 326/330 | 98.8 (96.9-99.5) |
| | Retrospective | 47/50 | 94.0 (83.8-97.9) | 526/527 | 99.8 (98.9-100) |
| | Prospective / Retrospective | 66/69A | 95.7 (88.0-98.5) | 852/857B | 99.4 (98.6-99.8) |
| | Contrived | 35/37C | 94.6 (82.3-98.5) | 739/740 | 99.9 (99.2-100) |
| | Overall | 101/106 | 95.3 (89.4-98.0) | 1591/1597 | 99.6 (99.2-99.8) |
#### Table 11: Clinical Performance for Enterobacter cloacae complex
A. A species of the Enterobacter cloacae complex was not detected in 1 false negative sample, but PCR/sequencing and MALDI-TOF instead detected E. coli. Standard laboratory procedures identified E. cloacae only.
B. E. cloacae was detected in 2/5 false positive samples using PCR/sequencing.
C. E. cloacae complex was not detected in 2 samples containing Enterobacter asburiae.
#### Table 12: Clinical Performance for Enterobacter (non-cloacae complex)
| Target | Sample Type | Sensitivity/PPA | | Specificity/NPA | |
|---------------------------------------|-----------------------------|-----------------|------------------|-----------------|------------------|
| | | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) |
| Enterobacter -non-<br>cloacae complex | Prospective (Fresh) | 3/3 | 100 (43.9-100) | 163/164 | 99.4 (96.6-99.9) |
| | Prospective (Frozen) | 5/7 | 71.4 (35.9-91.8) | 175/175 | 100 (97.9-100) |
| | Prospective (All) | 8/10 | 80.0 (49.0-94.3) | 338/339 | 99.7 (98.3-99.9) |
| | Retrospective | 12/12 | 100 (75.8-100) | 565/565 | 100 (99.3-100) |
| | Prospective / Retrospective | 20/22A | 90.9 (72.2-97.5) | 903/904B | 99.9 (99.4-100) |
| | Contrived | 36/36 | 100 (90.4-100) | 741/741 | 100 (99.5-100) |
| | Overall | 56/58 | 96.6 (88.3-99.0) | 1644/1645 | 99.9 (99.7-100) |
A. A species of the Enterobacter non-cloacae complex was not detected in 2 false negative samples. Standard laboratory procedures identified E. aerogenes and PCR/sequencing detected E. cloacae.,.
B. A species of the Enterobacter non-cloacae complex was not detected in the false positive sample using PCR/sequencing.
{20}------------------------------------------------
| Target | Sample Type | Sensitivity/PPA | | Specificity/NPA | |
|------------------|-----------------------------|-----------------|------------------|-----------------|------------------|
| | | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) |
| Escherichia coli | Prospective (Fresh) | 59/60 | 98.3 (91.1-99.7) | 106/107 | 99.1 (94.9-99.8) |
| | Prospective (Frozen) | 72/73 | 98.6 (92.6-99.8) | 109/109 | 100 (96.6-100) |
| | Prospective (All) | 131/133 | 98.5 (94.7-99.6) | 215/216 | 99.5 (97.4-99.9) |
| | Retrospective | 132/140 | 94.3 (89.1-97.1) | 435/437 | 99.5 (98.3-99.9) |
| | Prospective / Retrospective | 263/273 | 96.3 (93.4-98.0) | 650/653A | 99.5 (98.7-99.8) |
| | Contrived | 52/52 | 100 (93.1-100) | 725/725 | 100 (99.5-100) |
| | Overall | 315/325 | 96.9 (94.4-98.3) | 1375/1378 | 99.8 (99.4-99.9) |
#### Table 13: Clinical Performance for Escherichia coli
A. E. coli was detected in 3/3 false positive samples using PCR/sequencing.
#### Table 14: Clinical Performance for Fusobacterium necrophorum
| Target | Sample Type | Sensitivity/PPA | | Specificity/NPA | |
|------------------------------|-----------------------------|-----------------|------------------|-----------------|----------------|
| | | TP/TP+FN | % (95% CI) | TN/TN+FP | % (95% CI) |
| Fusobacterium<br>necrophorum | Prospective (Fresh) | 0/0 | ---…