(207 days)
The BD MAX Enteric Parasite Panel performed on the BD MAX System is an automated in vitro diagnostic test for the direct qualitative detection of enteric pathogens. The BD MAX Enteric Parasite Panel detects nucleic acids from:
Giardia lamblia
Cryptosporidium (C. hominis and C. parvum only), Entamoeba histolytica
Testing is performed on unpreserved or 10% formalin-fixed stool specimens from symptomatic patients with suspected gastroenteritis, or colitis. The assay is intended to aid in the diagnosis of gastrontestinal infection when used in conjunction with clinical evaluation and other laboratory findings. The test is performed directly on the specimen, utilizing real- time polymerase chain reaction (PCR) for the amplification of specific targets. The test utilizes fluorogenic gene-specific hybridization probes for detection of the amplified DNA.
This test is intended for use, in conjunction with clinical presentation, laboratory findings, and epidemiological information, as an aid in the differential diagnosis of Giardia lamblia, Cryptosporidium hominis, and C. parvum, as well as Entamoeba histolytica infections. Results of this test should not be used as the sole basis for diagnosis, treatment, or other patient management decision. Positive results do not rule out co-infection with other organisms that are not detected by this test and may not be the sole or definitive cause of patient illness. Negative results in the setting of clinical illness compatible with gastroenteritis and/or colitis may be due to infection by pathogens that are not detected by this test or non-infectious causes such as colitis, irritable bowel syndrome, or Crohn's disease.
The BD MAX™ Enteric Parasite Panel assay along with the BD MAX™ System are comprised of an instrument with associated hardware and accessories, disposable microfluidic cartridges. master mixes, unitized reagent strips, and extraction reagents. The instrument automates sample preparation including target lysis. DNA extraction and concentration, reagent rehydration, target nucleic acid amplification and detection using real-time PCR. The assay includes a Sample Processing Control (SPC) that is present in the Extraction Tube. The SPC monitors DNA extraction steps, thermal cycling steps, reagent integrity and the presence of inhibitory substances. The BD MAX™ System software automatically interprets test results. For the BD MAX™ Enteric Parasite Panel, a test result may be called POS, NEG or UNR (Unresolved) based on the amplification status of the targets and of the Sample Processing Control. IND (Indeterminate) or INC (Incomplete) results are due to BD MAXTM System failure.
The provided text describes the BD MAX™ Enteric Parasite Panel, a diagnostic test for detecting specific parasitic nucleic acids in stool samples. The submission K220193 is a 510(k) premarket notification to add the Copan FecalSwab™ Collection, Preservation, and Transport System as an acceptable specimen type for use with the existing BD MAX™ Enteric Parasite Panel (predicate device K143648).
Here's an analysis of the acceptance criteria and the study that proves the device meets them:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state acceptance criteria in a table format with associated performance for the FecalSwab addition. Instead, it describes a series of studies designed to demonstrate that the performance of the device with FecalSwab specimens is equivalent or comparable to its performance with existing (unpreserved) specimen types. The core acceptance criterion for this submission is that the FecalSwab specimens perform similarly enough to unpreserved specimens to be considered "substantially equivalent."
Here's a summary of the reported performance from the studies aiming to demonstrate this equivalence:
| Study/Criterion | Acceptance Metric (Implied) | Reported Device Performance (with FecalSwab) |
|---|---|---|
| Analytical Sensitivity (LoD) | LoD for FecalSwab fecal specimens should be similar to LoD of unpreserved stool specimens. | The same LoD values were obtained for the unpreserved specimens versus FecalSwab specimen for each of the three targets (Entamoeba histolytica, Cryptosporidium parvum, and Giardia lamblia), indicating equivalent analytical sensitivity. |
| Stability of Stool Specimens (FecalSwab) | Detection > 95% at target stability time points claimed in the package insert. | Detection > 95% occurred at all target stability time points. Stool preserved with FecalSwab can be stored for 48 hours (2 days) at 25 ± 2 °C and 120 hours (5 days) at 2 - 8 °C. Sample buffer tubes inoculated with FecalSwab specimen can be stored for 48 hours (2 days) at 25 ± 2 ℃ and 120 hours (5 days) at 2 - 8 ℃. |
| User Variability (FecalSwab Preparation) | Expected assay results should be obtained when FecalSwab stool specimens are prepared by multiple users. | The data demonstrate that expected assay results are obtained when FecalSwab stool specimens were prepared by multiple users. |
| Clinical Performance Comparison | Performance with FecalSwab specimen type should be comparable to the unpreserved stool specimen type. | Performance of the BD MAX™ Enteric Parasite Panel assay with the FecalSwab specimen type is comparable to the unpreserved stool specimen type (based on a comparison study of retrospectively collected clinical specimens and contrived specimens). |
2. Sample sizes used for the test set and the data provenance
The document provides very limited detail on specific sample sizes for the test sets.
- Analytical Sensitivity (LoD) Study: Not specified, but generally, LoD studies involve testing multiple replicates at various concentrations.
- Stability Study: Not specified, but implies a sufficient number of samples across different storage conditions and time points to achieve > 95% detection.
- User Variability Study: Not specified, but involved multiple users preparing FecalSwab tubes.
- Clinical Performance Comparison Study: "retrospectively collected clinical specimens." The exact number of specimens is not provided.
- Data Provenance: Retrospective clinical specimens. The country of origin is not specified.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
This information is not provided in the document. The studies described are primarily analytical and comparative evaluations of specimen types rather than diagnostic performance against a clinical ground truth established by experts. For the clinical comparison study, "retrospectively collected clinical specimens" were used, implying their original diagnostic status (positive/negative for specific parasites) served as a de facto ground truth, likely established by previous standard diagnostic methods or a combination of clinical and laboratory findings. No specific mention of experts or their qualifications for establishing this ground truth is made for this set of studies.
4. Adjudication method for the test set
The document does not mention any adjudication method. Since the studies focus on comparing a new specimen type to an existing one, the "truth" for the samples (especially in analytical studies) would be based on the known concentration of spiked organisms or the pre-established diagnostic status of clinical samples.
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
No, an MRMC comparative effectiveness study involving human readers and AI assistance was not done. This device is a molecular diagnostic test (PCR-based), not an AI-powered image analysis or interpretation tool that would involve human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, this can be considered a standalone performance evaluation of the assay. The BD MAX™ System "automates sample preparation including target lysis, DNA extraction and concentration, reagent rehydration, target nucleic acid amplification and detection using real-time PCR." The "software automatically interprets test results." There is no "human-in-the-loop" for the interpretation of the PCR results themselves beyond potentially reviewing unresolved or indeterminate results as per laboratory protocols. The studies evaluate the analytical and clinical performance of the automated system with different specimen inputs.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The ground truth used depends on the specific study type:
- Analytical Sensitivity (LoD): Likely based on known concentrations of target organisms spiked into fecal matrix, representing a quantitative "ground truth."
- Stability Study: Similar to LoD, based on known concentrations of spiked organisms.
- User Variability Study: Also likely based on known spiked concentrations in prepared samples.
- Clinical Performance Comparison: The ground truth for the retrospectively collected clinical specimens would be their pre-established diagnostic status, which would typically arise from standard of care laboratory methods (e.g., microscopy, culture, or other molecular tests) and clinical presentation at the time of original diagnosis. The document states "performance of the BD MAX™ Enteric Parasite Panel assay with the FecalSwab specimen type is comparable to the unpreserved stool specimen type," implying the original diagnosis on the unpreserved samples (or the consensus of prior methods) served as the comparator.
8. The sample size for the training set
The document does not specify a training set sample size. This submission is for an updated specimen claim for an existing device (BD MAX™ Enteric Parasite Panel, K143648), not the initial development or de novo training of the core algorithm. The studies conducted here are primarily validation/verification studies for the FecalSwab specimen type.
9. How the ground truth for the training set was established
Since no specific training set is mentioned for this particular submission (K220193), the method for establishing ground truth for a training set is not applicable to the information provided. The original predicate device (K143648) would have undergone its own development and validation, which would have involved establishing ground truth for its analytical and clinical studies.
§ 866.3990 Gastrointestinal microorganism multiplex nucleic acid-based assay.
(a)
Identification. A gastrointestinal microorganism multiplex nucleic acid-based assay is a qualitativein vitro diagnostic device intended to simultaneously detect and identify multiple gastrointestinal microbial nucleic acids extracted from human stool specimens. The device detects specific nucleic acid sequences for organism identification as well as for determining the presence of toxin genes. The detection and identification of a specific gastrointestinal microbial nucleic acid from individuals exhibiting signs and symptoms of gastrointestinal infection aids in the diagnosis of gastrointestinal infection when used in conjunction with clinical evaluation and other laboratory findings. A gastrointestinal microorganism multiplex nucleic acid-based assay also aids in the detection and identification of acute gastroenteritis in the context of outbreaks.(b)
Classification. Class II (special controls). The special controls are set forth in FDA's guideline document entitled: “Class II Special Controls Guideline: Gastrointestinal Microorganism Multiplex Nucleic Acid-Based Assays for Detection and Identification of Microorganisms and Toxin Genes from Human Stool Specimens.” For availability of the guideline document, see § 866.1(e).