Search Results

The intended use of Chiron Diagnostics ACS:180 Ferritin Assay is for the quantitative determination of Ferritin in serum or plasma using the Chiron Diagnostics ACS:180® Automated Chemiluminescence Systems. It is to be used to aid in the diagnosis of iron deficiency anemia and iron overload.

The Chiron Diagnostics ACS:180 Ferritin assay is a two-site sandwich immunoassay using direct, chemiluminometric technology, which uses constant amounts of two anti-ferritin antibodies. The first antibody, in the Reagent, is a polyclonal goat anti-ferritin antibody labeled with acridinium ester. The second antibody, in the Solid Phase, is a monoclonal mouse anti-ferritin antibody, which is covalently coupled to paramagnetic particles. The ACS:180 system automatically performs the following steps:

• dispenses 25 uL of sample into a cuvette .
• . dispenses 100 µL of Lite Reagent and 450 µL of Solid Phase and incubates for 7.5 minutes at 37°C
• . separates, aspirates, and washes the cuvettes with reagent water4
• . dispenses 300 uL each of Reagent 1 and Reagent 2 to initiate the chemiluminescent reaction
• . reports results according to the selected option, as described in the system operating instructions or in the online help system

A direct relationship exists between the amount of ferritin present in the patient sample and the amount of relative light units (RLUs) detected by the system.

Here's an analysis of the provided text regarding the acceptance criteria and supporting study for the Chiron Diagnostics ACS:180 Ferritin assay:

The document is a 510(k) summary for a medical device submitted to the FDA, which focuses on demonstrating substantial equivalence to a predicate device rather than setting new, explicit acceptance criteria in the same way a clinical trial might. However, performance characteristics are presented that implicitly serve as acceptance criteria for regulatory clearance based on equivalence.

1. Table of Acceptance Criteria and Reported Device Performance

• Mean 13.1 ng/mL: Within-run %CV = 2.76, Total %CV = 4.98
• Mean 54.8 ng/mL: Within-run %CV = 2.64, Total %CV = 6.07
• Mean 162.7 ng/mL: Within-run %CV = 2.73, Total %CV = 4.68
• Mean 359.5 ng/mL: Within-run %CV = 3.62, Total %CV = 5.08 |
  | Expected Results in Healthy and Diseased Populations: Values should align with known physiological ranges. | Expected Results:
• Normal Males (N=142): Geo. Mean = 94 ng/mL, 95th Percentile = 22-322 ng/mL
• Normal Females (N=134): Geo. Mean = 46 ng/mL, 95th Percentile = 10-291 ng/mL
• Iron Deficiency (N=60): Geo. Mean = 11.6 ng/mL, Total Observed Range = 0.68-34.5 ng/mL
• Other Anemias (N=7): Geo. Mean = 610.8 ng/mL, Total Observed Range = 13.0-1390.8 ng/mL
• Iron Overload (N=44): Geo. Mean = 1899.6 ng/mL, Total Observed Range = 334.6-8573.0 ng/mL
• Renal Dialysis (N=31): Geo. Mean = 312.3 ng/mL, Total Observed Range = 31.3-1321.2 ng/mL
• Chronic Liver Disease (N=34): Geo. Mean = 1967.1 ng/mL, Total Observed Range = 7.9-12826.0 ng/mL |

2. Sample Size for the Test Set and Data Provenance

• Method Comparison: 276 samples in the range of 3.1 to 1621 ng/mL were used for comparison against an alternate chemiluminescent method.
• Precision: 4 samples were assayed, each 3 times in 8 assays.
• Expected Results (Reference Ranges):
  • Normal Males: 142 subjects
  • Normal Females: 134 subjects
  • Iron Deficiency: 60 patients
  • Other Anemias: 7 patients
  • Iron Overload: 44 patients
  • Renal Dialysis: 31 patients
  • Chronic Liver Disease: 34 patients

Data Provenance: The document does not explicitly state the country of origin or whether the studies were retrospective or prospective. Given the nature of a 510(k) submission for an in-vitro diagnostic, these studies are typically conducted by the manufacturer as prospective analytical and clinical performance evaluations, but specific details are not provided.

3. Number of Experts and Qualifications for Ground Truth

Not applicable. This device is an in-vitro diagnostic assay for quantitative measurement. Its "ground truth" is established through analytical validation against reference methods, known concentrations, and correlation with clinical diagnoses rather than expert interpretation of images or clinical cases. The reference ranges for healthy and sick populations are derived from the observed values in those cohorts, where the diagnosis of the condition itself would have been made by medical professionals, but this isn't "expert adjudication" of device output.

4. Adjudication Method for the Test Set

Not applicable. As noted above, this is a quantitative immunoassay, not a diagnostic imaging or interpretive device that requires expert adjudication of its output.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

Not applicable. This is an IVD for quantitative measurement of a biomarker, not a diagnostic imaging aid for human interpretation. Therefore, an MRMC study comparing human readers with and without AI assistance is not relevant to this device.

6. Standalone (Algorithm Only) Performance

Yes, the studies presented are standalone performance studies of the assay device. The "Method Comparison" and "Precision" sections directly evaluate the analytical performance of the ACS:180 Ferritin assay without human-in-the-loop interpretation of its quantitative results. The "Expected Results" section provides reference ranges and observed values in different patient populations, demonstrating the device's ability to produce diagnostically relevant results on its own.

7. Type of Ground Truth Used

• Analytical Performance (Sensitivity, Reportable Range, Precision): Ground truth is established through known concentrations of ferritin controls, international reference standards (if applicable, though not specified here), and replicate measurements using the device itself.
• Method Comparison: The "ground truth" for method comparison is the results obtained from an "alternate chemiluminescent method," suggesting an established, comparable method already in use.
• Expected Results: The ground truth for the clinical categories (e.g., "Normal Males," "Iron Deficiency," "Iron Overload") is based on clinical diagnosis of the subjects/patients included in those cohorts. The document states, "The following values for patients with several diagnosed conditions were determined," implying the patients were already diagnosed with these conditions through standard clinical practice before their samples were tested.

8. Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of machine learning or AI development. For an immunoassay like this, the development process involves reagent formulation and optimization, calibration, and internal validation studies. The reported performance characteristics likely represent the outcome of extensive internal development and validation, but specific "training set" sizes are not applicable as there isn't an algorithm being trained in the typical AI sense.

9. How Ground Truth for the Training Set was Established

Not applicable for this type of device. As explained in point 8, the concept of a "training set" and associated ground truth establishment (in the AI/ML context) is not relevant for the development and validation of a traditional immunoassay device. The assay development would involve ensuring accurate measurement through chemical and immunological principles, using calibrated materials, and verifying performance through analytical and clinical validation studies as detailed in the document.

Ask a specific question about this device