(265 days)
The xTAG® Gastrointestinal Pathogen Panel (GPP) is a multiplexed nucleic acid test intended for the simultaneous qualitative detection and identification of multiple viral, parasitic, and bacterial nucleic acids in human stool specimens from individuals with signs and symptoms of infectious colitis or gastroenteritis. The following pathogen types, subtypes and toxin genes are identified using the xTAG GPP:
- Campylobacter (C. jejuni, C. coli and C. lari only) .
- Clostridium difficile (C. difficile) toxin A/B ●
- Cryptosporidium (C. parvum and C. hominis only) ●
- Escherichia coli (E. coli) 0157 .
- Enterotoxigenic Escherichia coli (ETEC) LT/ST ●
- Giardia (G. lamblia only also known as G. intestinalis and G. duodenalis)
- . Norovirus GI/GII
- . Rotavirus A
- Salmonella ●
- Shiga-like Toxin producing E. coli (STEC) stx 1/stx 2 .
- Shigella (S. boydii, S. sonnei, S. flexneri and S. dysenteriae) ●
The detection and identification of 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, laboratory findings and epidemiological information. A gastrointestinal microorganism multiplex nucleic acid-based assay also aids in the detection and identification of acute gastroenteritis in the context of outbreaks.
xTAG® GPP positive results are presumptive and must be confirmed by FDAcleared tests or other acceptable reference methods.
The results of this test should not be used as the sole basis for diagnosis, treatment, or other patient management decisions. Confirmed positive results do out rule out coinfection with other organisms that are not detected by this test, and may not be the sole or definitive cause of patient illness. Negative xTAG® Gastrointestinal Pathogen Panel results in the setting of clinical illness compatible with gastroenteritis may be due to infection by pathogens that are not detected by this test or non-infectious causes such as ulcerative colitis, irritable bowel syndrome, or Crohn's disease.
xTAG GPP is not intended to monitor or guide treatment for C. difficile infections.
The xTAG GPP is indicated for use with the Luminex® MAGPIX® instrument.
The xTAG® Gastrointestinal Pathogen Panel (GPP) is a multiplexed nucleic acid test.
Here's an analysis of the provided text, outlining the acceptance criteria and study details for the xTAG® Gastrointestinal Pathogen Panel (GPP):
Device Name: xTAG® Gastrointestinal Pathogen Panel (GPP)
Regulation Number: 21 CFR 866.3990
Regulation Name: Gastrointestinal microorganism multiplex nucleic acid-based assay
Regulatory Class: Class II
Product Code: PCH, NSU, JJH
This document is a marketing clearance (510(k)) letter from the FDA, granting substantial equivalence to the xTAG® GPP. While it defines the device and its intended use, it does not contain the detailed study results, acceptance criteria, or performance data typically found in the submission package. The letter refers to the submission document (K121894) where this information would be located.
Therefore, many of the requested details cannot be extracted directly from the provided text. I will indicate where the information is not available in this document.
Acceptance Criteria and Study to Prove Device Meets Acceptance Criteria
1. Table of Acceptance Criteria and Reported Device Performance
- Acceptance Criteria: Not explicitly stated in this document.
- Reported Device Performance: Not explicitly stated in this document.
To fulfill this section, one would typically need access to the original 510(k) submission (K121894) or associated peer-reviewed publications. The performance data would usually involve sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for each pathogen detected by the panel, compared against a reference method.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: Not available in this document.
- Data Provenance (e.g., country of origin, retrospective/prospective): Not available in this document.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
- Number of Experts: Not available in this document.
- Qualifications of Experts: Not available in this document.
4. Adjudication Method for the Test Set
- Adjudication Method: Not available in this document.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
- MRMC Study: This type of study (comparing human readers with and without AI assistance) is typically relevant for interpretative diagnostic devices, especially those involving image analysis. The xTAG® GPP is a multiplex nucleic acid test, which is an in vitro diagnostic (IVD) device that directly detects pathogens from a sample. Therefore, an MRMC study is not applicable to this type of device. The test itself generates a result (positive/negative for specific pathogens), not an image for human interpretation that would be "assisted" by AI.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
- Standalone Performance: For an IVD like the xTAG® GPP, the "algorithm" is the entire assay process (sample preparation, nucleic acid extraction, amplification, detection using xTAG technology, and data analysis software). The performance is inherently standalone in terms of generating a result from a sample. The device performance itself (sensitivity, specificity) reported in the 510(k) would represent this standalone performance. However, the specific metrics are not available in this document.
7. The Type of Ground Truth Used
- Type of Ground Truth: While not explicitly stated here, for an IVD diagnostic device, the ground truth for performance studies is typically established by FDA-cleared reference methods (e.g., culture, PCR, or other gold-standard diagnostic tests) or a composite reference standard (combining multiple methods, sometimes with expert review) for each pathogen. The document states: "xTAG® GPP positive results are presumptive and must be confirmed by FDA-cleared tests or other acceptable reference methods." This implies that the ground truth used in validation studies would have relied on such reference methods.
8. The Sample Size for the Training Set
- Sample Size for Training Set: Not applicable in the traditional sense for this type of IVD. This device is a molecular diagnostic assay, not a machine learning model that undergoes "training" on a dataset in the same way an image recognition AI would. The "training" of such a device involves assay development, optimization, and analytical validation. However, there would be validation sample sizes, which are not available in this document.
9. How the Ground Truth for the Training Set was Established
- Ground Truth for Training Set: As above, the concept of a "training set" and its "ground truth" establishment in the context of an IVD is different from AI/ML. Assay development and analytical validation would use samples characterized by established reference methods to ensure the assay performs as expected. The details are not available in this document.
Summary of Missing Information from the Provided Document:
The provided FDA clearance letter (K121894) confirms the device's regulatory status and indications for use but does not contain the detailed technical performance data, study design, or ground truth establishment methods. This information would be found in the original premarket notification submission itself.
§ 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).