(66 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 antimicrobial Ertapenem at concentrations of 0.03 - 32 mcg/ml to Pasco Panels. Ertapenem has been shown to be active in vitro against most strains of microorganisms listed below, as described in the FDA-approved package insert for this antimicrobic.
Active In Vitro and in Clinical Infectious Against:
Aerobic Gram-positive microorganisms Staphylococcus aureus (methicillin-susceptible strains only)
Aerobic Gram-negative microorganisms Escherichia coli Klebsiella pneumoniae
Active In Vitro but their clinical significance is unknown
Aerobic Gram-negative microorganisms
Citrobacter freundii Citrobacter koseri Enterobacter aerogenes Enterobacter cloacae Klebsiella oxytoca (excluding ESBL producing strains) Morganella morganii Proteus mirabilis Proteus vulgaris Serratia marcescens
Pasco Panels are used for quantitatively measuring 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. Varving concentrations of antimicrobial agents (usually in two-fold dilutions) are dispensed into the Pasco microdilution 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.
1. Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria (Essential Agreement, EA) | Reported Device Performance (EA) | Acceptance Criteria (Category Agreement, CA) | Reported Device Performance (CA) |
|---|---|---|---|
| ≥ 90% for Staphylococci spp. | 98.3% | ≥ 90% with no very major or major errors for methicillin-susceptible Staphylococci spp. | 100% (no very major or minor errors) |
| ≥ 90% for Enterobacteriaceae | 99.6% | ≥ 90% with acceptable minor discrepancies for Enterobacteriaceae | 99.4% (5 random minor discrepancies, all within EA) |
Note: The acceptance criteria for Essential Agreement (EA) and Category Agreement (CA) are implicitly derived from the context of "acceptable" and the high percentages reported, aligning with typical AST performance standards. The document explicitly states "Category Agreement (CA) was acceptable at 99.4% with 5 random minor discrepancies, all of which were within EA." and "No major (M) or very major (VM) errors were observed" for Enterobacteriaceae, indicating these are key performance indicators for acceptance.
2. Sample Size and Data Provenance for Test Set:
- Sample Size:
- Staphylococci spp.: 410 challenge and clinical strains
- Enterobacteriaceae: 574 challenge and clinical strains
- QC organisms: 10 organisms for reproducibility testing across 3 sites, each tested in triplicate on 3 separate days. (Total 90 tests per site for reproducibility).
- Data Provenance: The study used "challenge strains, fresh clinical isolates, stock clinical isolates and QC strains." The data was collected at "three test sites." The specific country of origin is not mentioned, but the submission is to the U.S. FDA, implying relevance to the U.S. market. The use of "fresh clinical isolates" suggests prospective collection for those samples, while "stock clinical isolates" implies a mix of retrospective and potentially prospective uses. "Challenge strains" and "QC strains" are typically laboratory-maintained strains.
3. Number and Qualifications of Experts for Ground Truth:
The document does not explicitly state the number of experts used to establish ground truth or their specific qualifications (e.g., "radiologist with 10 years of experience"). However, for antimicrobial susceptibility testing, the "reference methodology" (presumably a standard such as broth microdilution or agar dilution as per NCCLS guidelines) serves as the ground truth. This reference methodology is typically performed by trained microbiologists or laboratory personnel following established protocols.
4. Adjudication Method for Test Set:
The document does not describe an explicit adjudication method (like 2+1 or 3+1). The "reference methodology" is considered the standard against which the Pasco panels are compared. Discrepancies are reported (e.g., 5 random minor discrepancies for Enterobacteriaceae), and the agreement (Essential and Category) is calculated based on direct comparison to the reference method. There's no indication of a separate expert review or adjudication process for conflicting results between the test device and the reference method, beyond standard laboratory quality control.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not performed. This type of study is more common in diagnostic imaging where human readers interpret results with and without AI assistance. This submission describes an in vitro diagnostic device (Antimicrobial Susceptibility Test) where the output is typically an objective measurement (MIC) or category (S/I/R), not an interpretation that varies significantly between human readers in the same way an imaging study would. The study focuses on comparing the device's performance against a reference laboratory method.
6. Standalone Performance Study:
Yes, a standalone study was done. The document describes the performance of the Pasco MIC and MIC/ID Panels directly against a "reference methodology." The results for Essential Agreement, Category Agreement, and reproducibility are reported for the device itself, without human-in-the-loop assistance for interpretation beyond reading the visible growth or color changes as per the package insert instructions.
7. Type of Ground Truth Used:
The ground truth used was the reference methodology for antimicrobial susceptibility testing. The text states: "Challenge strains, fresh clinical isolates, stock clinical isolates and QC strains were tested concurrently using both Pasco methodology and reference methodology..." This implies a standard, accepted laboratory method (e.g., broth microdilution or agar dilution as per NCCLS guidelines) as the gold standard for determining the true MIC and susceptibility category.
8. Sample Size for the Training Set:
The document does not specify a separate training set sample size or clearly delineate it from the test set. For in vitro diagnostic devices like AST panels, the "training set" in the context of an algorithm or AI is not typically applicable in the same way as for imaging devices. The "training" for such devices often involves optimizing the panel design, reagent concentrations, and interpretation rules during product development, which is usually done on a larger, internal set of diverse isolates, but this is not reported as a separate "training set" in the 510(k) summary. The clinical testing described primarily serves as validation (test set).
9. How Ground Truth for the Training Set Was Established:
As no distinct "training set" is explicitly mentioned, the method for establishing its ground truth is not detailed. However, if any internal development or optimization involved using ground truth, it would almost certainly have been established using similar reference methodology as described for the validation (test set).
§ 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).