(161 days)
The MicroScan® Dried Gram-Negative MIC/Combo Panel is used to determine quantitative and/or qualitative antimicrobial agent susceptibility of colonies grown on solid media of rapidly growing aerobic and facultative anaerobic gram-negative bacilli. After inoculation, panels are incubated for 16 - 20 hours at 35°C +/- 1°C in a non-CO2 incubator, and read either visually or with MicroScan instrumentation. according to the Package Insert.
This particular submission is for the addition of the antimicrobial Ertapenem at concentrations of 0.002 to 32 mcg/ml to the test panel.
The gram-negative organisms which may be used for Ertapenem susceptibility testing in this panel are:
Citrobacter freundii Citrobacter koseri Enterobacter aerogenes Enterobacter cloacae Escherichia coli Klebsiella oxytoca (excluding ESBL producing strains) Klebsiella pneumoniae Morganella morganii Proteus mirabilis Proteus vulgaris Serratia marcescens
MicroScan® Dried Gram-Negative MIC/Combo Panels are designed for use in determining quantitative and/or qualitative antimicrobial agent susceptibility of colonies grown on solid media of rapidly growing aerobic and facultative anaerobic Gram-Negative bacilli.
The antimicrobial susceptibility tests are miniaturizations of the broth dilution susceptibility test that have been diluted in broth and dehydrated. Various antimicrobial agents are diluted in broth to concentrations bridging the range of clinical interest. Panels are rehydrated with water after inoculation with a standardized suspension of the organism. After incubation in a non-CO2 incubator for 16-20 hours, the minimum inhibitory concentration (MIC) for the test organism is read by determining the lowest antimicrobial concentration showing inhibition of growth.
This 510(k) summary describes the MicroScan® Dried Gram-Negative MIC/Combo Panels with Ertapenem, an antimicrobial susceptibility test system.
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Overall Essential Agreement (compared to NCCLS frozen Reference Panel) | >97% for Ertapenem |
| Inoculum and Instrument Reproducibility | Acceptable reproducibility and precision for Ertapenem (with Turbidity and Prompt inoculum methods, and autoSCAN-4 and WalkAway® instruments) |
| Quality Control Testing | Acceptable results for Ertapenem |
2. Sample Size Used for the Test Set and Data Provenance:
The document does not explicitly state the exact sample size for the test set in terms of the number of isolates. However, it mentions that the external evaluation was conducted with:
- Fresh and stock Efficacy isolates
- Stock Challenge strains
The data provenance is not specified regarding the country of origin. The study was a comparison to an NCCLS frozen Reference Panel, suggesting a controlled, laboratory-based evaluation. It is a retrospective evaluation, as it uses existing isolates and challenge strains.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:
The document does not specify the number or qualifications of experts used to establish the ground truth. It states that Challenge strains were compared to "Expected Results determined prior to the evaluation," and the primary comparison was against an "NCCLS frozen Reference Panel." This implies that the ground truth was established by a reference method rather than expert consensus on individual cases from a test set.
4. Adjudication Method for the Test Set:
No adjudication method is mentioned. The performance is assessed by direct comparison of the device's results to those of the NCCLS frozen Reference Panel.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done:
No, an MRMC comparative effectiveness study was not done. This study focuses on the agreement of the device with a reference method, not on human reader performance with or without AI assistance.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done:
Yes, this was a standalone performance study. The MicroScan® Dried Gram-Negative MIC/Combo Panel is an automated or semi-automated system designed to determine susceptibility, and its performance was evaluated against a reference standard without direct human intervention in the interpretation phase for the purposes of the study measurement. While human interaction is involved in setting up the test and potentially reading panels (visually or via instrumentation), the performance being measured is of the device's ability to produce an MIC value or categorization, not the human interpretation of that value.
7. The Type of Ground Truth Used:
The primary ground truth used was the results from an NCCLS frozen Reference Panel. Additionally, for challenge strains, "Expected Results determined prior to the evaluation" served as the ground truth. This indicates a reference standard method was used as the ground truth.
8. The Sample Size for the Training Set:
The document does not specify a training set or its sample size. This type of submission (for a diagnostic device, especially for an AST system) typically focuses on validation against a reference standard as opposed to a machine learning model that undergoes explicit training.
9. How the Ground Truth for the Training Set was Established:
As no training set is described, the method for establishing its ground truth is not applicable.
§ 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).