(56 days)
The Liofilchem® MIC Test Strip (MTS) is a quantitative method intended for the in vitro determination of antimiorobial susceptibility of bacteria. MTS consists of specialized paper impregnated with a pre-defined concentration gradient of an antimicrobial agent, which is used to determine the minimum inhibitory concentration (MIC) in ug/ml. o f antimicrobial agents against bacteria as tested on agar media using overnight incubation and manual reading procedures.
The Azithromycin MTS at concentrations of 0.016-256 ug/mL should be interpreted at 16-20 hours of incubation.
Azithromycin has been shown to be active both clinically and in viro against the non-fastidious bacteria listed below according to the FDA label:
Staphylococcus aureus (including methicillin-resistant isolates)
MTS consists of specialized paper impregnated with a pre-defined concentration gradient of an antimicrobial agent, which is used to determine the minimum inhibitory concentration (MIC) in ug/ml. o f antimicrobial agents against bacteria as tested on agar media using overnight incubation and manual reading procedures.
This is an FDA 510(k) clearance letter for the Liofilchem MIC Test Strip (MTS), Azithromycin 0.016 - 256 µg/mL. This device is an antimicrobial susceptibility test and does not involve AI or human image interpretation. Therefore, many of the requested categories are not applicable.
Here's the information that can be extracted from the provided text:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state "acceptance criteria" for the device, nor does it provide a direct table of "reported device performance" in the typical sense of sensitivity, specificity, or predictive values. Instead, the clearance is based on the device being "substantially equivalent" to legally marketed predicate devices. The "Indications for Use" section indicates the intended performance:
| Category | Description / Performance |
|---|---|
| Intended Use | Quantitative method for in vitro determination of antimicrobial susceptibility of bacteria. |
| Measurement | Determine Minimum Inhibitory Concentration (MIC) in µg/mL of antimicrobial agents against bacteria. |
| Incubation Period | 16-20 hours of incubation. |
| Reading Procedure | Manual reading procedures. |
| Antimicrobial Agent | Azithromycin |
| Concentration Range | 0.016-256 µg/mL |
| Active Against (Example) | Staphylococcus aureus (including methicillin-resistant isolates) - Note: The document states "Azithromycin has been shown to be active both clinically and in vitro against the non-fastidious bacteria listed below according to the FDA label," but only Staphylococcus aureus is listed in the provided text snippet. This implies the device is intended to accurately measure susceptibility against this organism.* |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document does not provide details about a specific "test set" sample size or data provenance. This information would typically be found in the 510(k) submission itself, which is not fully available here. The clearance letter only confirms that the FDA reviewed the submission.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
This is not applicable as the device is for in vitro diagnostic testing, not for interpretation of medical images by human experts. The "ground truth" for antimicrobial susceptibility testing is typically established through reference methods (e.g., broth microdilution) rather than expert consensus on images.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable for this type of device. Adjudication methods are relevant for studies involving human interpretation of ambiguous data, which is not the case for this in vitro diagnostic.
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
Not applicable. This device is an antimicrobial susceptibility test strip and does not involve AI assistance for human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This is a physical test strip that requires manual reading, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
For antimicrobial susceptibility testing, the "ground truth" is typically established by comparing the device's results to a reference method (e.g., Clinical and Laboratory Standards Institute (CLSI) broth microdilution or agar dilution methods). The document does not explicitly state which reference method was used, but it is implied that such comparisons were part of the substantial equivalence determination.
8. The sample size for the training set
The document does not provide details about a "training set" or its sample size. This information would be specific to the development and validation studies within the 510(k) submission, not typically stated in the clearance letter.
9. How the ground truth for the training set was established
As above, details about a "training set" are not provided. For this type of device, if such a concept were applied, the ground truth would be established by 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).