(73 days)
PASCO MIC AND MIC/ID PANELS are used for quantitatively measuring (with the exception of the Breakpoint/ID panel which provides qualitative measurement or category results) the susceptibility of rapidly growing aerobic and facultative anaerobic bacterial pathogens to a battery of antimicrobial agents and determining the biochemical identification of those organisms. This 510(k) notification is for the addition Imipenem to Pasco panels at concentrations of 0.015 to 2 mcg/ml for use in determining the susceptibility of S. pneumoniae and non-pneumococcal streptococci.
Varying concentrations of antimicrobial agents (usually in two-fold dilutions) are dispensed into the Pasco panels and the panels are then frozen. Panels are thawed prior to use, inoculated with the test organisms, incubated the traditional 16-24 hours and panels are then observed for visible growth or color changes as described in the package insert. The lowest concentration of each antimicrobial agent with no apparent visible growth of the test organism is recorded as the minimum inhibitory concentration (MIC). Changes in pH and production of specific metabolites from growth in biochemical substrates are interpreted as described in the package insert for conventional tubed media.
Here's an analysis of the provided text regarding the acceptance criteria and study for the Pasco MIC and MIC/ID Panels, focusing on the addition of Imipenem:
Acceptance Criteria and Device Performance
| Acceptance Criteria (Not explicitly stated as criteria, but implied by performance) | Reported Device Performance |
|---|---|
| S. pneumoniae strains: | |
| Acceptable Essential Agreement (EA) | 98.7% (with 1 minor error) |
| Acceptable Major (M) errors | Not observed |
| Acceptable Very Major (VM) errors | Not observed |
| Acceptable Category Agreement (CA) | 100% (with 9 additional random minor errors noted, all within EA) |
| Non-pneumococcal strains: | |
| Acceptable Essential Agreement (EA) | 100% (on initial testing) |
| Acceptable Major (M) errors | Not observed |
| Acceptable Very Major (VM) errors | Not observed |
| Acceptable Minor errors | Not observed |
| Acceptable Category Agreement (CA) | 100% (with no random minor errors noted) |
| Reproducibility: | |
| Overall reproducibility within ±1 dilution | 100% |
| QC Endpoints (for S. pneumoniae ATCC 49619): | |
| Within recommended NCCLS acceptable range | Within recommended NCCLS acceptable range (from both reference and Pasco panels throughout testing) |
Study Details
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Sample size used for the test set and the data provenance:
- S. pneumoniae strains: 101 strains. The provenance is described as "CDC challenge strains and clinical isolates," tested at two sites.
- Non-pneumococcal strains: 130 strains. The provenance is described as "CDC challenge strains and clinical isolates," tested at two sites.
- Reproducibility testing: 12 organisms at each site.
- Data Provenance: The text indicates "two sites" for comparative testing but does not specify the country of origin. It uses "CDC challenge strains," which usually refers to strains from the Centers for Disease Control and Prevention (USA), and "clinical isolates," which suggests recent patient samples. The study appears to be prospective in nature for these tests, as they were "performed at two sites."
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
The document does not specify the number of experts or their qualifications for establishing the ground truth. The "reference panel" is used for comparison, implying a gold standard or a method accepted as ground truth, but who interpreted or established that ground truth is not mentioned. -
Adjudication method for the test set:
The document does not specify an adjudication method like 2+1 or 3+1. The ground truth appears to be established by a "reference panel" and then compared to the Pasco test panel's results. -
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:
This is not applicable. The device described is an Antimicrobial Susceptibility Test panel, not an AI-assisted diagnostic tool for human readers. It's an in-vitro diagnostic device that provides quantitative or qualitative results. -
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
Yes, this can be considered a standalone performance study. The device, the Pasco MIC and MIC/ID Panels, is designed to produce results (MIC, essential agreement, category agreement) based on the growth or non-growth of organisms. The "performance" refers to the accuracy of the panel itself in determining susceptibility, not the performance of a human interpreting an image or output from an algorithm in a human-in-the-loop scenario. The comparison is between the Pasco panel and a "reference panel." -
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
The ground truth was established by a "reference panel". This typically refers to an established, validated method (e.g., broth microdilution or agar dilution as per NCCLS guidelines) that is considered the gold standard for antimicrobial susceptibility testing. The text also mentions "OC endpoints for the OC organism S. pneumoniae ATCC 49619... were within the recommended NCCLS acceptable range," indicating adherence to a recognized standard (NCCLS - National Committee for Clinical Laboratory Standards, now CLSI). -
The sample size for the training set:
The document describes a "comparative testing" for device performance, but it does not mention a separate "training set" as would be typical for machine learning models. The study appears to be a validation of the device's performance against a reference method using challenge strains and clinical isolates. -
How the ground truth for the training set was established:
Since no explicit training set is described in the context of machine learning, this question is not applicable. For the performance evaluation, the "reference panel" results served as the ground truth.
§ 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).