(72 days)
To determine bacterial antimicrobial agent susceptibility
The MicroScan MICroSTREP plus® Panel is used to determine quantitative and/or qualitative antimicrobial agent susceptibility of colonies grown on solid media of aerobic streptococci, including Streptococcus pneumoniae. After inoculation, panels are incubated for 20 – 24 hours at 35°C +/- 1°C in a non-CO2 incubator, and read visually according to the Package Insert. Additionally, the panels may be incubated in and read by a MicroScan® WalkAway instrument.
This particular submission is for the addition of instrument read capability of the antimicrobial Erythromycin, at concentrations of 0.015 to 2 mcg/ml on the MicroScan MICroSTREP plus® Panel.
The organisms which may be used for Erythromycin susceptibility testing on this panel are:
Streptococcus pneumoniae Streptococcus pyogenes viridans group streptococci
The MicroScan MICroSTREP plus® Panel is used to determine quantitative and/or qualitative antimicrobial agent susceptibility of colonies grown on solid media of aerobic streptococci, including Streptococcus pneumoniae. After inoculation, panels are incubated for 20 – 24 hours at 35°C +/- 1°C in a non-CO2 incubator, and read according to the Package Insert.
The antimicrobial susceptibility tests are miniaturizations of the broth dilution susceptibility test. Various antimicrobial agents are diluted in water, buffer or minute concentrations of broth to concentrations bridging the range of clinical interest. Panels are rehydrated with 15 µl Mueller-Hinton broth supplemented with 2-5% lysed horse blood (LHB) and buffered with 50 mM HEPES, after inoculation of the broth with a standardized suspension of the organism in saline. After incubation in a non-CO2 incubator for 20-24 hours, the minimum inhibitory concentration (MIC) for the test organism is manually read by observing the lowest antimicrobial concentration showing inhibition of growth. Additionally, the panels may be incubated in and read by a MicroScan® WalkAway instrument.
This 510(k) summary describes the MicroScan MICroSTREP plus® Panel for determining bacterial susceptibility to Erythromycin using a MicroScan® WalkAway instrument an in vitro diagnostic device.
Here's a breakdown of the requested information:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance (Erythromycin) |
|---|---|
| Overall Essential Agreement (compared to Expected Result) | 98.6% |
| Instrument Reproducibility | Acceptable |
| Quality Control Testing | Acceptable |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not explicitly stated as a number. The document mentions "stock and CDC Challenge strains" for external evaluation. It indicates the study was designed to confirm acceptability by comparing performance with "Expected Results determined before the evaluation," implying a retrospective comparison against a pre-established reference standard.
- Data Provenance: The document refers to "external evaluation" but does not specify the country of origin of the data. The use of "CDC Challenge strains" suggests a U.S. context for some of the strains, but this doesn't definitively determine the origin of all test data.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- This information is not provided in the given text. The ground truth (referred to as "Expected Result" or "CLSI frozen Reference Panel") was established prior to the evaluation, but the specifics of who established it or their qualifications are not detailed.
4. Adjudication Method for the Test Set
- This information is not provided. The document states that the test set's performance was compared with an "Expected Result generated on a CLSI frozen Reference Panel." This implies a reference standard rather than multi-expert adjudication for individual test cases.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
- No, an MRMC comparative effectiveness study was not done. This device is an automated instrument for reading antimicrobial susceptibility panels, not an AI intended to assist human readers in interpretation. Therefore, the concept of "how much human readers improve with AI vs without AI assistance" is not applicable here.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Yes, a standalone performance evaluation was conducted. The study assesses the performance of the MicroScan® WalkAway instrument in reading the MICroSTREP plus® Panel with Erythromycin. The performance is compared against an "Expected Result," implying the instrument's automated reading capability without human intervention for interpretation.
7. The Type of Ground Truth Used
- The ground truth used was based on an Expected Result generated on a CLSI frozen Reference Panel and determined before the evaluation. This serves as a reference standard for antimicrobial susceptibility testing.
8. The Sample Size for the Training Set
- This information is not provided. The document describes an evaluation of an existing measurement instrument with an added capability, not the development or training of a new algorithm. It does not mention a training set in the context of an AI/ML model where a training set would be explicitly defined.
9. How the Ground Truth for the Training Set Was Established
- This information is not applicable/provided as no training set for an AI/ML model is described or referenced in the document.
§ 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).