(79 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 of Amoxicillin/ Clavulanic Acid to Pasco panels at concentrations of 0.015/0.0075 to 8/4 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.
This document describes the validation of the Pasco MIC and MIC/ID Panels for antimicrobial susceptibility testing, specifically for the inclusion of Amoxicillin/Clavulanic Acid.
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Metric | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Essential Agreement (EA) | Not explicitly stated but generally high (e.g., >90-95%) | S. pneumoniae: 97.4% (initial), 100% (retesting) |
| Non-pneumococcal streptococci: 99.2% (initial) | ||
| Category Agreement (CA) | Not explicitly stated but generally high (e.g., >90-95%) | S. pneumoniae: 100% (with 23 minor errors) |
| Non-pneumococcal streptococci: 100% (with 3 random minor errors) | ||
| Reproducibility | 100% within acceptable plus or minus 1 dilution | 100% within +/- 1 dilution (11 of 12 organisms with on-scale endpoints) |
| QC Endpoints | Within recommended NCCLS acceptable range | Within recommended NCCLS acceptable range |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size:
- Streptococcus pneumoniae: 101 strains
- Non-pneumococcal streptococci: 130 strains
- Data Provenance: The study was conducted at "two sites" using "CDC challenge strains and clinical isolates." This suggests a combination of laboratory-controlled and potentially real-world (clinical isolates) data. The country of origin is not explicitly stated but implies U.S. context given the FDA submission. The nature of "challenge strains" and "clinical isolates" indicates a prospective or pseudo-prospective approach for the testing phase.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
The document does not explicitly state the number or qualifications of experts used to establish the ground truth. However, "reference panel" testing was performed, implying that comparison was made against an established, validated method or panel. This "reference panel" likely represents the 'ground truth' and would have been interpreted by trained laboratory personnel or microbiologists.
4. Adjudication Method for the Test Set
The document does not specify a formal adjudication method (like 2+1 or 3+1). The comparison was made against a "reference panel." Any discrepancies would likely have been resolved by reviewing the results against the reference method's interpretation, possibly with retesting, as indicated by the "retesting" for S. pneumoniae.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not conducted or described. This study focuses on the standalone performance of the Pasco panels against a reference method, not on human reader performance with or without AI assistance.
6. Standalone Performance
Yes, a standalone performance study was done. The study directly compared the Pasco MIC and MIC/ID Panels (algorithm/device) to a "reference panel" to assess their accuracy in determining antimicrobial susceptibility.
7. Type of Ground Truth Used
The ground truth used was based on a reference panel. This implies that the results from the Pasco MIC/ID panels were compared to an established, gold-standard method for determining minimum inhibitory concentrations (MICs) and category results for antimicrobial susceptibility. This is a common practice in in-vitro diagnostic device validation.
8. Sample Size for the Training Set
The document does not provide information about a separate "training set" or its sample size. This type of device (antimicrobial susceptibility panel) typically relies on pre-defined chemical reactions and measurements rather than machine learning algorithms that require explicit training sets. The "Pasco MIC and MIC/ID Panels" are described as containing varying concentrations of antimicrobial agents, suggesting a fixed-format assay rather than an adaptive, learnable system.
9. How the Ground Truth for the Training Set Was Established
Since no separate training set is mentioned or implied for an AI/machine learning model, the concept of establishing ground truth for a training set is not applicable here. The device's "training" or development would have involved optimizing the chemical formulations, concentrations, and interpretive rules based on established microbiological principles and validated reference methods.
§ 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).