The MicroScan Dried Gram-Negative MIC/Combo Panel is used to determine quantitative and qualitative antimicrobial agent susceptibility of colonies grown on solid media of rapidly growing aerobic and facultative anaerobic gram-negative bacilli. After inoculation, panels are incubated for 16-20 hours at 35°C ± 1°C in a non-CO2 incubator, and read either visually or with MicroScan instrumentation, according to the Package Insert.

This particular submission is for the addition of the antimicrobial cefepime at concentrations of 0.12-64 µg/mL to the test panel. Testing is indicated for Enterobacterales, Pseudomonas aeruginosa and Aeromonas spp., as recognized by the FDA Susceptibility Test Interpretive Criteria (STIC) webpage.

The MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (CPE) (0.12-64µg/mL) has demonstrated acceptable performance with the following organisms:

Enterobacterales (Enterobacter spp., Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Citrobacter koseri, (formerly Citrobacter diversus), Citrobacter freundii complex (Citrobacter freudnii, Citrobacter werkmanii and Citrobacter youngae), Klebsiella oxytoca, Morganella morganii, Proteus vulgaris, Providencia stuartii, Providencia rettgeri, Serratia marcescens)

Pseudomonas aeruginosa

Aeromonas spp.

Device Description

MicroScan Dried Gram-Negative MIC/Combo Panels are designed for use in determining quantitative and qualitative antimicrobial agent susceptibility of colonies grown on solid media of rapidly growing aerobic and facultative anaerobic gram-negative bacilli.

The principle of MicroScan panels with antimicrobial susceptibility tests are miniaturizations of the broth dilution susceptibility test that have been diluted in broth and dehydrated. Various antimicrobial agents are diluted in broth to concentrations bridging the range of clinical interest. Panels are rehydrated with water after inoculation with a standardized suspension of the organism. After incubation in a non-CO2 incubator for 16-20 hours, the minimum inhibitory concentration (MIC) for the test organism is read by determining the lowest antimicrobial concentration showing inhibition of growth.

The product is single-use and intended for laboratory professional use.

AI/ML Overview

Device Performance Acceptance Criteria and Study Details for MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime

Based on the provided FDA 510(k) Clearance Letter, the device in question is the MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (CPE) (0.12-64 µg/mL), which is an Antimicrobial Susceptibility Test (AST) System. The study described focuses on demonstrating the substantial equivalence of this new configuration (with Cefepime) to a predicate device.

Given the nature of the device (an AST System), the "acceptance criteria" are typically related to the accuracy of determining Minimum Inhibitory Concentration (MIC) and the resulting categorical agreement (Susceptible, Intermediate, Resistant) compared to a reference method. The "study that proves the device meets the acceptance criteria" refers to the performance evaluation conducted for the 510(k) submission.

1. Table of Acceptance Criteria and Reported Device Performance

For AST systems, the key performance metrics are Essential Agreement (EA) and Categorical Agreement (CA) when compared to a CLSI (Clinical and Laboratory Standards Institute) frozen reference panel. The FDA document "Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA", dated August 28, 2009, likely outlines the specific acceptance criteria thresholds for EA and CA. While the exact numerical acceptance criteria are not explicitly stated in the provided text, the performance "demonstrated acceptable performance" implies meeting these pre-defined thresholds.

Performance Metric	Organism Group (Inoculation/Read Method)	Reported Device Performance (Essential Agreement)	Reported Device Performance (Categorical Agreement)	Acceptance Criteria (Implied / Based on FDA Guidance for AST)
Essential Agreement (EA)	Aeromonas spp. (Prompt Inoculation/WalkAway Instrument)	93.5%	N/A	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Categorical Agreement (CA)	Aeromonas spp. (Prompt Inoculation/WalkAway Instrument)	N/A	90.3%	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Essential Agreement (EA)	Pseudomonas aeruginosa (Prompt Inoculation/WalkAway Instrument)	95.7%	N/A	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Categorical Agreement (CA)	Pseudomonas aeruginosa (Prompt Inoculation/WalkAway Instrument)	N/A	91.4%	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Essential Agreement (EA)	Enterobacterales (Turbidity Method/WalkAway Instrument)	94.7%	N/A	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Categorical Agreement (CA)	Enterobacterales (Turbidity Method/WalkAway Instrument)	N/A	96.3%	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Essential Agreement (EA)	Aeromonas spp. (Turbidity Inoculation/autoSCAN-4 and Manual Reads)	100.0%	N/A	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Essential Agreement of Evaluable Isolates	Aeromonas spp. (Turbidity Inoculation/autoSCAN-4 and Manual Reads)	100.0%	N/A	N/A (Supplementary metric)
Categorical Agreement (CA)	Aeromonas spp. (Turbidity Inoculation/autoSCAN-4 and Manual Reads)	N/A	87.1%	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Categorical Agreement (CA)	Aeromonas spp. (Turbidity Inoculation/WalkAway Read Method)	N/A	Below 90%	Typically ≥ 90% (Guidance based, not explicitly stated as a number)
Inoculum and Instrument Reproducibility	Cefepime (Turbidity/Prompt, autoSCAN-4/WalkAway)	Acceptable Reproducibility and Precision	N/A	(Implied acceptable performance)
Quality Control Testing	Cefepime	Acceptable Results	N/A	(Implied acceptable performance)

Important Note: The document highlights some instances where the performance was "outside of essential agreement" for Enterobacterales with Prompt inoculation and "below 90%" for Aeromonas spp. with turbidity inoculation and WalkAway read method. These discrepancies are "mitigated with a limitation" in the product labeling, suggesting that while initial performance in those specific conditions did not meet implicit criteria, the overall robust performance with other methods/organisms, coupled with labeling limitations, made the device acceptable for clearance.

2. Sample Size Used for the Test Set and Data Provenance

Sample Size: The document does not explicitly provide a total number for the test set sample size (e.g., number of isolates tested). It refers to "contemporary and stock Efficacy isolates and stock Challenge strains" used for external evaluations.
Data Provenance: The document does not specify the country of origin of the data. It mentions "external evaluations," which generally implies testing conducted at clinical sites or contract research organizations. The study appears to be retrospective in the sense that it uses "stock Efficacy isolates and stock Challenge strains" which are pre-existing collections of bacterial isolates. It also mentions "contemporary" isolates, suggesting some recent collection. It implies a laboratory-based performance study rather than a clinical trial with patient outcomes.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

This type of device (AST System) does not typically rely on human expert interpretation for establishing the "ground truth" of the test set. The ground truth for antimicrobial susceptibility testing is established by a reference method, which for this device is stated as a "CLSI frozen Reference Panel."

Therefore:

Number of Experts: Not applicable in the context of creating the ground truth for AST.
Qualifications of Experts: Not applicable.

4. Adjudication Method for the Test Set

As the ground truth is established by a reference method (CLSI frozen Reference Panel), there is no human adjudication method like 2+1 or 3+1 typically used for image-based diagnostics. The device's results are directly compared to the quantitatively or qualitatively determined results from the CLSI reference method.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

There is no indication that an MRMC comparative effectiveness study was performed. This type of study is not relevant for this device, which is an automated or manually read laboratory diagnostic for antimicrobial susceptibility, not an AI-assisted diagnostic tool that aids human readers in interpretation. The device itself performs the susceptibility test.

6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done

Yes, the performance data presented is effectively standalone performance of the device (MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime). The device "read either visually or with MicroScan instrumentation" and its performance (Essential Agreement, Categorical Agreement) is directly compared to the reference standard. The "human-in-the-loop" would be the laboratory professional reading the results, and the study evaluates the accuracy of the device itself in producing those results. Where visual reads are mentioned, it's about the device's ability to produce clear inhibition patterns for visual interpretation, not a human independently interpreting raw data without the device.

7. The Type of Ground Truth Used

The ground truth used was established by a CLSI frozen Reference Panel. This is a recognized and standardized method for determining antimicrobial susceptibility, often involving broth microdilution or agar dilution methods where organisms are tested against known concentrations of antimicrobials. It is a highly controlled and quantitative method to determine the true MIC value against which the device's performance is compared.

8. The Sample Size for the Training Set

The document does not mention a training set or any details about its sample size. This is consistent with the nature of the device. AST systems are generally rule-based or empirically derived systems based on established microbiological principles, rather than machine learning models that require distinct training sets. The development of such panels involves extensive empirical testing during the R&D phase to ensure the correct concentrations and formulations, but this isn't typically referred to as a "training set" in the context of an AI/ML model.

9. How the Ground Truth for the Training Set was Established

As no training set (in the AI/ML sense) is indicated, this point is not applicable.

Summary

FDA 510(k) Clearance Letter - MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime

Page 1

U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov

Doc ID # 04017.08.00

August 20, 2025

Beckman Coulter, Inc.
Ashley Austerman
Senior Regulatory Affairs Analyst
1584 Enterprise Blvd
West Sacramento, California 95691

Re: K243804
Trade/Device Name: MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (CPE) (0.12-64 µg/mL) (MicroScan)
Regulation Number: 21 CFR 866.1640
Regulation Name: Antimicrobial Susceptibility Test Powder
Regulatory Class: Class II
Product Code: LTT, JWY, LRG, LTW
Dated: July 15, 2025
Received: July 18, 2025

Dear Ashley Austerman:

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 (the 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 available 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.

FDA's substantial equivalence determination also included the review and clearance of your Predetermined Change Control Plan (PCCP). Under section 515C(b)(1) of the Act, a new premarket notification is not

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K243804 - Ashley Austerman Page 2

required for a change to a device cleared under section 510(k) of the Act, if such change is consistent with an established PCCP granted pursuant to section 515C(b)(2) of the Act. Under 21 CFR 807.81(a)(3), a new premarket notification is required if there is a major change or modification in the intended use of a device, or if there is a change or modification in a device that could significantly affect the safety or effectiveness of the device, e.g., a significant change or modification in design, material, chemical composition, energy source, or manufacturing process. Accordingly, if deviations from the established PCCP result in a major change or modification in the intended use of the device, or result in a change or modification in the device that could significantly affect the safety or effectiveness of the device, then a new premarket notification would be required consistent with section 515C(b)(1) of the Act and 21 CFR 807.81(a)(3). Failure to submit such a premarket submission would constitute adulteration and misbranding under sections 501(f)(1)(B) and 502(o) of the Act, respectively.

Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

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 requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.

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K243804 - Ashley Austerman Page 3

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/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-devices/device-advice-comprehensive-regulatory-assistance/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,

Ribhi Shawar -S

Ribhi Shawar, Ph.D. (ABMM)
Branch Chief, General Bacteriology and Antimicrobial Susceptibility Branch
Division of Microbiology Devices
OHT7: Office of In Vitro Diagnostics
Office of Product Evaluation and Quality
Center for Devices and Radiological Health

Enclosure

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FORM FDA 3881 (8/23) Page 1 of 1

DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration

Indications for Use

Form Approved: OMB No. 0910-0120
Expiration Date: 07/31/2026
See PRA Statement below.

510(k) Number (if known): K243804

Device Name: MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (Cpe) (0.12 - 64 µg/mL)

Indications for Use (Describe)

The MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (CPE) (0.12-64µg/mL) has demonstrated acceptable performance with the following organisms:

Pseudomonas aeruginosa

Aeromonas spp.

Type of Use (Select one or both, as applicable)

☒ Prescription Use (Part 21 CFR 801 Subpart D)
☐ Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

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510(k) Summary

510(k) Submission Information:

Device Manufacturer: Beckman Coulter
Contact name: Ashley Austerman, Senior Regulatory Affairs Analyst
Phone: 916-248-8868
Fax: 916-374-2480
Date prepared: August 19, 2025
Product Name: Microdilution Minimum Inhibitory Concentration (MIC) Panels
Trade Name: MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (CPE) (0.12 – 64 µg/mL)
Intended Use: To determine antimicrobial agent susceptibility
Classification: Class II
Product Code: LTT, JWY, LRG, LTW
510(k) Notification: Updated antimicrobial agent - Cefepime
Predicate device: MicroScan Dried Gram-Negative MIC/Combo Panels Ceftazidime – (K202343)

510(k) Summary:

Device Description: MicroScan Dried Gram-Negative MIC/Combo Panels are designed for use in determining quantitative and qualitative antimicrobial agent susceptibility of colonies grown on solid media of rapidly growing aerobic and facultative anaerobic gram-negative bacilli.

The product is single-use and intended for laboratory professional use.

Intended Use: For use with MicroScan Dried Gram Negative MIC/Combo, Dried Gram-Negative Breakpoint Combo panels. MicroScan Gram Negative panels are designed for use in determining antimicrobial agent susceptibility of aerobic and facultatively anaerobic gram-negative bacilli.

Indications for Use: The MicroScan Dried Gram-Negative MIC/Combo Panel is used to determine quantitative and qualitative antimicrobial agent susceptibility of colonies grown on solid media of rapidly growing aerobic and facultative anaerobic gram-negative bacilli. After inoculation, panels are incubated for 16-20 hours at 35°C ± 1°C in a non-CO2 incubator, and read either visually or with MicroScan instrumentation, according to the Package Insert.

The MicroScan Dried Gram-Negative MIC/Combo Panels with Cefepime (CPE) (0.12-64µg/mL) has demonstrated acceptable performance with the following organisms:

Enterobacterales (Enterobacter spp., Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Citrobacter koseri, (formerly Citrobacter diversus), Citrobacter freundii complex (Citrobacter freundii, Citrobacter werkmanii and Citrobacter youngae), Klebsiella oxytoca, Morganella morganii, Proteus vulgaris, Providencia stuartii, Providencia rettgeri, Serratia marcescens)

Pseudomonas aeruginosa

Aeromonas spp.

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Substantial Equivalence Information:

The similarities and differences of the MicroScan Dried Gram Negative MIC/Combo Panels with Cefepime (Cpe) (0.12-64 µg/mL) compared to the predicate device, MicroScan Dried Gram Negative MIC/Combo Panels with Ceftazidime – (K202343), are described below in Table 1.

Table 1: Substantial Equivalence

Similarities

Item	Proposed MicroScan Dried Gram-Negative MIC/Combo Panels – cefepime	Predicate MicroScan Dried Gram-Negative MIC/Combo Panels – ceftazidime (K202343)
Intended Use	Determination of susceptibility to cefepime with gram-negative bacteria	Determination of susceptibility to ceftazidime with gram-negative bacteria
Technology	Overnight Microdilution MIC Susceptibility Tests	Same
Specimen	Isolated colonies from cultures	Same
Incubation Temperature	35º C ± 1 º C	Same
Incubation Atmosphere	Aerobic	Same
Incubation Time	16 – 20 hours	Same
Reading Method	Automated or Manual	Same

Differences

Item	Proposed MicroScan Dried Gram-Negative MIC/Combo Panels – cefepime	Predicate MicroScan Dried Gram-Negative MIC/Combo Panels – ceftazidime (K202343)
Antimicrobial Agent	Dried Cefepime 0.12 – 64 µg/mL	Dried Ceftazidime 0.5 – 64 µg/mL

Performance and Conclusion:

The proposed MicroScan Dried Gram-Negative MIC/Combo Panel demonstrated substantially equivalent performance when compared with a CLSI frozen Reference Panel, as defined in the FDA document, "Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA", dated August 28, 2009. The Premarket Notification (510[k]) presents data in support of the MicroScan Dried Gram-Negative MIC/Combo Panel with Cefepime.

The external evaluations were conducted with contemporary and stock Efficacy isolates and stock Challenge strains. The external evaluations were designed to confirm the acceptability of the proposed Dried Gram-Negative Panel by comparing its performance with a CLSI frozen Reference panel. The Dried Gram-Negative Panel inoculated with Prompt and read on the WalkAway instrument demonstrated acceptable performance with Aeromonas spp. Essential Agreement (EA) 93.5% and Categorical Agreement (CA) of 90.3% as well as Pseudomonas aeruginosa EA of 95.7% and CA of 91.4% for Cefepime when compared with the frozen Reference panel. The Dried Gram-Negative Panel inoculated with turbidity method and read on the WalkAway instrument demonstrated acceptable performance with Enterobacterales EA of 94.7% and CA of 96.3%.

Organism reporting group performance for the remaining read and inoculation methods along with associated labeling limitations and statements meet acceptance criteria. Results obtained with Enterobacterales and cefepime for all read methods with Prompt inoculation system were outside of essential agreement when compared to the reference method. The performance is mitigated with a limitation to retest Enterobacterales with turbidity inoculation, if critical to patient care. The turbidity inoculation for Aeromonas spp. with autoSCAN-4 and manual reads had Essential agreements at 100.0% and Essential Agreement of Evaluable isolates at 100.0%, however, the categorical agreements were 87.1%. Essential agreement of evaluable isolates was

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100% and the majority of the categorical discrepancies were minor errors. When turbidity inoculation and the WalkAway read method is utilized with Aeromonas spp., the categorical agreement is below 90% and therefore, the performance is mitigated with a proposed limitation.

Inoculum and instrument reproducibility testing demonstrated acceptable reproducibility and precision with Cefepime, regardless of which inoculum method (i.e. Turbidity or Prompt), or instrument (autoSCAN-4 instrument or WalkAway system) was used.

Quality Control testing demonstrated acceptable results for Cefepime.

Beckman Coulter, the stylized logo, and the Beckman Coulter product and service marks mentioned herein are trademarks or registered trademarks of Beckman Coulter, Inc. in the United States and other countries.

Regulation Number and Section

§ 866.1640 Antimicrobial susceptibility test powder.

(a)
Identification. An antimicrobial susceptibility test powder is a device that consists of an antimicrobial drug powder packaged in vials in specified amounts and intended for use in clinical laboratories for determining in vitro susceptibility of bacterial pathogens to these therapeutic agents. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases.(b)
Classification. Class II (performance standards).