(73 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 Meropenem at concentrations of 0.03 to 4 mcg/ml to the test panel
The organisms which may be used for Meropenem susceptibility testing in this panel are:
Streptococcus pneumoniae (excluding penicillin-resistant strains) Viridans group streptococci
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-CO 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 an analysis of the acceptance criteria and study detailed in the provided 510(k) summary:
1. Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance (Meropenem) |
|---|---|
| Overall Essential Agreement with NCCLS frozen Reference Panel | 99.1% |
| Reproducibility | Acceptable |
| Quality Control Testing | Acceptable |
Note: The specific numerical threshold for "acceptable" reproducibility and quality control is not explicitly stated in the summary, only that the results were deemed acceptable.
2. Sample Size Used for the Test Set and Data Provenance
The summary does not explicitly state the exact sample size for the test set. It mentions "fresh and stock Efficacy isolates and stock Challenge strains" were used for the external evaluation. The provenance of the data (country of origin, retrospective/prospective) is not specified.
3. Number of Experts and Qualifications for Ground Truth Establishment
The summary does not provide information on the number or qualifications of experts used to establish the ground truth for the test set. The ground truth was established by an "NCCLS frozen Reference Panel," implying a standardized, presumably expert-validated, method.
4. Adjudication Method for the Test Set
The summary does not describe an adjudication method for the test set. The external evaluation compared the MicroScan® MICroSTREP plus™ Panel directly against an NCCLS frozen Reference panel.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This device is an in vitro diagnostic (IVD) for antimicrobial susceptibility testing, not a medical imaging or diagnostic device that would typically involve human readers interpreting results in a comparative study.
6. Standalone (Algorithm Only) Performance Study
Yes, a standalone study was conducted. The MicroScan® MICroSTREP plus™ Panel's performance was evaluated by comparing its results directly with an NCCLS frozen Reference Panel. There isn't a "human-in-the-loop" component described for interpreting the panel's results in this evaluation, as the panels are read visually according to the package insert. The comparison is between two automated/semi-automated methods of determining MIC.
7. Type of Ground Truth Used
The ground truth used was an NCCLS frozen Reference Panel. This is a standardized, recognized reference method for antimicrobial susceptibility testing, providing a benchmark for accuracy.
8. Sample Size for the Training Set
The summary does not explicitly mention a "training set" or its sample size. For an IVD device like this, the development process likely involves internal testing and calibration with various strains, but this information is not detailed in the provided 510(k) summary, which focuses on the validation of the final product.
9. How the Ground Truth for the Training Set Was Established
As no specific "training set" is described for this type of device in the summary, information on how its ground truth was established is not provided. The development of such panels would typically involve extensive testing against established reference methods, much like the external evaluation described for the final product.
§ 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).