(54 days)
Remel RPMI 1640 Agar w/ MOPS and 2% Glucose is a solid medium recommended for use with antibiotic gradient-based systems for quantitative determination of susceptibility to antifungal agents when testing Candida spp. directly from colonies grown on nonselective media.
RPMI-1640 was developed by Moore et al. at Roswell Park Memorial Institute. The formulation is based on the RPMI- 1630 series of media utilizing a bicarbonate buffering system and alterations in the amounts of amino acids and vitamins. RPMI-1640 medium has demonstrated wide applicability in cell culture and also as the reference method for antifungal broth microdilution recommended by Clinical Laboratory Standards Institute (CLSI). When properly supplemented with MOPS, glucose, and agar RPMI-1640 has demonstrated accuracy for use with gradient-based systems with results comparable to that obtained with the CLSI reference method for testing Candida spp. against antifungal agents. The gradient method is based on a combination of the concepts of both dilution and diffusion tests, but differs from conventional disk methods by the use of a preformed, stable antibiotic gradient strip. When the strip is applied to the inoculated agar plate, there is an immediate release of the antibiotic into the agar matrix. A continuous and exponential gradient of antibiotic concentration is created beneath the carrier. After incubation a symmetrical inhibition ellipse centered along the carrier is seen. The zone edge intersects the strip at the minimum inhibitory concentration (MIC) value given in ug/ml. For antifungal testing, due to trailing effect, MICs should be read at approximately 90% inhibition of growth, ignoring faint hazes and minute colonies for flucytosine and 80% inhibition for fluconazole and itraconazole.
The provided document describes a 510(k) premarket notification for a culture medium (Remel RPMI 1640 Agar w/ MOPS and 2% Glucose) used for antifungal susceptibility testing. It is a submission for a new in-vitro diagnostic device, not an AI/ML powered medical device. Therefore, much of the requested information (e.g., sample size for test set, number of experts, adjudication method, MRMC study, standalone performance, training set details) is not applicable or cannot be extracted from this type of document, as it pertains to AI/ML device evaluation.
However, I can extract information related to the device's intended use and comparison to a predicate device, which implicitly defines its acceptance criteria in the context of a 510(k) submission (i.e., substantial equivalence to the predicate).
Here's an analysis based on the available information:
1. Table of Acceptance Criteria and Reported Device Performance
For this type of device (culture medium), "acceptance criteria" are implied by demonstrating substantial equivalence to a legally marketed predicate device. This typically involves showing that the new device performs similarly in its intended application. The document focuses on comparing the characteristics of the new device to its predicate.
| Characteristic | Acceptance Criteria (Implied by Predicate) | Reported Device Performance (Remel RPMI 1640 Agar w/ MOPS and 2% Glucose) |
|---|---|---|
| Intended Use | Quantitative determination of susceptibility to methicillin and oxacillin when testing staphylococci directly from colonies grown on nonselective media, using antibiotic gradient-based systems. (Predicate: Mueller Hinton Agar w/ 2% NaCl) | Quantitative determination of susceptibility to antifungal agents when testing Candida spp. directly from colonies grown on nonselective media, using antibiotic gradient-based systems. (Device: RPMI 1640 Agar w/ MOPS and 2% Glucose) |
| Incubation | 35° C (Predicate) | 35° C (Device) |
| Inoculation | Staphylococcus spp. (Predicate) | Candida spp. (Device) |
| Technology | To be used with predefined and preformed oxacillin gradient on a plastic strip. (Predicate) | To be used with predefined and preformed antifungal gradient on a plastic strip. Single antifungal agent per strip. (Device) |
| Interpretation | MIC is read at the end point where there is complete inhibition. (Predicate) | MICs should be read at approximately 90% inhibition of growth ignoring faint hazes and minute colonies for Flucytosine and 80% inhibition for Fluconazole and Itraconazole. (Device) |
| Key Performance | The 510(k) summary states, "When properly supplemented with MOPS, glucose, and agar RPMI-1640 has demonstrated accuracy for use with gradient-based systems with results comparable to that obtained with the CLSI reference method for testing Candida spp. against antifungal agents." | The 510(k) summary states, "When properly supplemented with MOPS, glucose, and agar RPMI-1640 has demonstrated accuracy for use with gradient-based systems with results comparable to that obtained with the CLSI reference method for testing Candida spp. against antifungal agents." |
2. Sample size used for the test set and the data provenance
The document does not specify a "test set" sample size in the context of AI/ML evaluation. It mentions "results comparable to that obtained with the CLSI reference method," implying that studies were conducted to compare the device's performance against a recognized standard using relevant microbial strains and antifungal agents. However, specific numbers of isolates, data origin (country), or whether the data was retrospective or prospective are not detailed in this summary.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
This information is not applicable and not provided. The "ground truth" for this type of device would typically be established by established microbiological methods (e.g., CLSI reference method) and not by expert human graders of images or features.
4. Adjudication method for the test set
This information is not applicable and not provided.
5. 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 an AI/ML powered device, so an MRMC study related to AI assistance is not applicable.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This is not an AI/ML powered device, so standalone algorithm performance is not applicable.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for evaluating the performance of this culture medium would be the Minimum Inhibitory Concentration (MIC) values determined by a Clinical and Laboratory Standards Institute (CLSI) reference method. The submission explicitly states the device's results are "comparable to that obtained with the CLSI reference method."
8. The sample size for the training set
This is not an AI/ML powered device, so a "training set" in that context is not applicable.
9. How the ground truth for the training set was established
This is not an AI/ML powered device, so "ground truth for the training set" is not applicable.
Summary of the Study Proving Acceptance Criteria:
The document indicates that the device's performance was evaluated by comparing its results to those obtained with the CLSI reference method for antifungal susceptibility testing of Candida spp. against antifungal agents. This comparison demonstrated "accuracy for use with gradient-based systems with results comparable" to the CLSI reference method. While specific study details (like sample size numbers, statistical methods, or full data tables) are not provided in this 510(k) summary, the statement about comparability to the CLSI reference method is the core evidence presented to establish substantial equivalence and thus, acceptance. The "acceptance criteria" were met by demonstrating that the new culture medium provides reliable and comparable MIC results when used with antibiotic gradient-based systems for Candida spp. as per established microbiological standards.
§ 866.1700 Culture medium for antimicrobial susceptibility tests.
(a)
Identification. A culture medium for antimicrobial susceptibility tests is a device intended for medical purposes that consists of any medium capable of supporting the growth of many of the bacterial pathogens that are subject to antimicrobial susceptibility tests. The medium should be free of components known to be antagonistic to the common agents for which susceptibility tests are performed in the treatment of disease.(b)
Classification. Class II (performance standards).