(56 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. This particular submission is for the addition of the antimicrobial Vancomvcin at concentrations of 0.06 to 8 mcg/ml to the test panel. The organisms which may be used for Vancomycin susceptibility testing in this panel are: Streptococcus pneumoniae (including penicillin-resistant strains), Streptococcus pyogenes, Streptococcus agalactiae, the viridans group, Streptococcus bovis.
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. 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 115 ul 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 (MC) for the test organism is manually read by observing the lowest antimicrobial concentration showing inhibition of growth.
Here's a breakdown of the acceptance criteria and the study details for the MicroScan® MICroSTREP plus™ Panel with Vancomycin, based on the provided text:
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Acceptance Criteria | Reported Device Performance (MicroScan® MICroSTREP plus™ Panel with Vancomycin) |
|---|---|---|
| Essential Agreement | Not explicitly stated as a percentage, but implied to be "acceptable performance" as defined by FDA DRAFT document "Guidance on Review Criteria for Assessment of Antimicrobial Susceptibility Devices", dated March 8, 2000. Typically, this refers to a high percentage agreement (e.g., >90-95%) between the candidate device and the reference method for MIC results. | 99.5% for Vancomycin (when compared with the frozen Reference panel). |
| Reproducibility | Implied to be "acceptable" | Demonstrated acceptable reproducibility and precision with Vancomycin. |
| Quality Control | Implied to be "acceptable" | Demonstrated acceptable results for Vancomycin. |
Study Details
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Sample size used for the test set and the data provenance:
- Sample Size: Not explicitly stated as a number. The text mentions "fresh and stock Efficacy isolates and stock Challenge strains" were used for external evaluation.
- Data Provenance: Not explicitly stated (e.g., country of origin). It's a "Premarket Notification (510/k])" which implies internal company evaluation and then submission to the FDA. The nature of the isolates (fresh, stock, challenge) suggests a mix, potentially collected over time or specifically prepared.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Number of Experts: Not specified.
- Qualifications of Experts: Not specified.
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Adjudication method for the test set:
- Not applicable/Not described. The ground truth appears to be based on an "NCCLS frozen Reference Panel," which acts as the comparator, rather than a human consensus adjudication process for the test results. The device results are compared against this reference, not human expert reads of the device itself.
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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:
- No MRMC comparative effectiveness study was done. This device is an in vitro diagnostic (IVD) panel for determining antimicrobial susceptibility, not an AI-assisted diagnostic tool for human readers. The "reading" is visual observation of growth inhibition from the panel, not an interpretation of medical images or complex data by human readers.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- This is an in vitro diagnostic (IVD) panel. The "algorithm" is the biochemical process within the panel and the visual interpretation rules. The performance reported (Essential Agreement, Reproducibility, Quality Control) is inherently the device's performance in generating results that are then visually read by a human. While the final interpretation is human-dependent, the device itself is designed to produce a quantitative result (MIC), and the reported performance reflects its accuracy in doing so compared to a reference standard. Therefore, in a sense, the "standalone" or intrinsic performance of the panel's ability to produce the correct MIC is what was evaluated against the reference.
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The type of ground truth used:
- NCCLS frozen Reference Panel. This is a recognized standard for antimicrobial susceptibility testing, considered a gold standard (or a very high-quality reference standard) for comparing new susceptibility testing methods.
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The sample size for the training set:
- Not applicable/Not described. This device is a biochemical in vitro diagnostic panel, not a machine learning algorithm that requires a training set.
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How the ground truth for the training set was established:
- Not applicable. As this is not a machine learning algorithm, there is no training set or associated ground truth establishment method.
§ 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).