Search Results
Found 1 results
510(k) Data Aggregation
(283 days)
The AutoDELFIA® Neonatal 17a-OH-progesterone kit is intended for the quantitative determination of human 17a-OH-progesterone in blood specimens dried on filter paper as an aid in screening newborns for congenital adrenal hyperplasia (CAH) using the 1235 AutoDELFIA® automatic immunoassay system.
The AutoDELFIA Neonatal 17α-OH-progesterone (17-OHP) assay is a solid phase, time-resolved fluoroimmunoassay based on the competitive reaction between europium-labeled 17-OHP and sample 17-OHP for a limited amount of binding sites on 17-OHP specific polyclonal antibodies (derived from rabbit). Danazol facilitates the release of 17-OHP from the binding proteins. A second antibody, directed against rabbit IgG, is coated to the solid phase, giving convenient separation of the antibody-bound and free antigen. Enhancement Solution dissociates europium ions from the labeled antigen into solution where they form highly fluorescent chelates with components of the Enhancement Solution. The fluorescence in each well is then measured. The fluorescence of each sample is inversely proportional to the concentration of 17-OHP in the sample.
Here's a summary of the acceptance criteria and the study that proves the device meets them, based on the provided text:
Device: AutoDELFIA® Neonatal 17α-OH-progesterone kit (B024)
Intended Use: Quantitative determination of human 17α-OH-progesterone in blood specimens dried on filter paper as an aid in screening newborns for congenital adrenal hyperplasia (CAH) using the 1235 AutoDELFIA® automatic immunoassay system.
1. Table of Acceptance Criteria and Reported Device Performance
The document describes the proposed device (B024) as substantially equivalent to a predicate device (K042425, B015) and highlights differences in performance characteristics. The acceptance criteria are implicitly defined by demonstrating similar or improved performance compared to the predicate device, especially regarding cross-reactivity and screening efficacy.
| Characteristic | Acceptance Criteria (Implied by Predicate) | Reported Proposed Device (B024) Performance |
|---|---|---|
| Antibody Cross-Reactions | Lower cross-reactivity with physiologically important steroids in neonates than predicate device. | 17α-OH pregnenolone sulfate: 0.78 % (Predicate: 2.0 %) 11-Deoxycortisol: 0.62 % (Predicate: 1.82 %) 17α-OH pregnenolone: 0.83 % (Predicate: 1.20 %) Progesterone: 0.37 % (Predicate: 0.47 %) |
| Analytical Sensitivity / Limit of Blank (LoB) | 1.3 ng/mL serum (Predicate) | 0.37 ng/mL serum (Improved) |
| Analytical Sensitivity / Limit of Detection (LoD) | Not explicitly stated for predicate in table, but overall analytical sensitivity is desired to be good. | 0.84 ng/mL serum (Improved over predicate's LoB) |
| Analytical Sensitivity / Limit of Quantitation (LoQ) | Not explicitly stated for predicate in table. | 1.4 ng/mL serum |
| Precision (Total Variation, full calibration curve) | CV% values for various concentrations (e.g., 13.2% for 25.9 ng/mL, 10.8% for 53.0 ng/mL, 10.9% for 114 ng/mL) | Range of CV% values (e.g., 13.0% for 2.12 ng/mL, 9.8% for 4.69 ng/mL, 14.8% for 7.52 ng/mL, 8.3% for 27.0 ng/mL, 9.2% for 54.4 ng/mL, 10.8% for 109 ng/mL, 9.1% for 182 ng/mL) |
| Precision (Total Variation, one calibration curve per 4 plates) | CV% values for various concentrations (e.g., 14.0% for 25.8 ng/mL, 12.4% for 52.9 ng/mL, 11.8% for 115 ng/mL) | Range of CV% values (e.g., 14.0% for 2.25 ng/mL, 12.0% for 4.89 ng/mL, 15.8% for 7.79 ng/mL, 9.7% for 27.7 ng/mL, 10.5% for 55.7 ng/mL, 12.7% for 113 ng/mL, 11.3% for 188 ng/mL) |
| Screening Efficacy (CAH case detection) | Must detect known CAH cases similarly or better than predicate device. | Detected all known CAH cases in studies at appropriate cut-off with one exception for very high percentiles. For instance, in Study 1, ≥ 2250 g, 90th percentile, 13 out of 13 CAH cases were detected. In Study 2, ≥ 2250 g, 90th percentile, 13 out of 13 CAH cases were detected. (See * below for exception) |
| Median Values in Newborn Screening | Comparable patterns to predicate, potentially with lower absolute values due to reduced cross-reactivity. | For Studies 1 & 2, median values for various weight categories were consistently lower for B024 compared to B015, supporting the claim of reduced cross-reactivity and increased specificity. |
In Study 1, < 1250 g, 95th percentile, the new kit detected 1 out of 2 CAH cases (the other case was due to maternal CAH treatment impacting the results). In Study 2, ≥ 2250 g, 95th percentile, using percentiles higher than the 90th resulted in one false negative out of 13 clinically confirmed CAH samples. The document notes that laboratories should consider this when setting screening cut-offs.
The Study Proving Device Meets Acceptance Criteria
The device's performance was evaluated through screening efficacy studies performed in two newborn screening laboratories, comparing the proposed kit (B024) to the predicate device (B015).
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Sizes:
- Study 1:
- < 1250 g: 364 subjects (Tables 2 & 3)
- 1250-2249 g: 500 subjects (Tables 4 & 5)
- ≥ 2250 g: 1328 subjects (Tables 6 & 7)
- Total Study 1: 2192 subjects
- Study 2:
- < 1250 g: 168 subjects (Tables 8 & 9)
- 1250-2249 g: 372 subjects (Tables 10 & 11)
- ≥ 2250 g: 1299 subjects (Tables 12 & 13)
- Total Study 2: 1839 subjects
- Total Samples for Screening Efficacy: 2192 + 1839 = 4031 subjects (pooled studies, across different weight categories and percentiles).
- Known CAH Cases:
- Study 1: 17 confirmed CAH cases.
- Study 2: 13 confirmed CAH cases (all in ≥ 2250g category).
- Study 1:
- Data Provenance: Retrospective specimens and excess samples. The country of origin is not explicitly stated, but the submitter is Wallac Oy, Finland, suggesting the studies likely occurred in European or Western laboratories.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document refers to "confirmed CAH case samples" and "clinically confirmed CAH samples." It does not specify the number of experts or their qualifications directly involved in establishing the ground truth for the individual test samples. The implication is that the CAH diagnoses were established clinically prior to the samples being used for the study.
4. Adjudication Method for the Test Set
The document does not describe an explicit adjudication method (e.g., 2+1, 3+1) for the ground truth of the test set samples. It relies on previously "confirmed" or "clinically confirmed" CAH diagnoses.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done
No, an MRMC comparative effectiveness study was not done. This device is an in-vitro diagnostic (IVD) kit that provides quantitative measurements, not an imaging AI algorithm requiring human reader interpretation with or without AI assistance. The comparison is between the performance of two IVD kits.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Yes, this was a standalone performance study. The device (immunoassay kit) directly produces a quantitative result (17-OHP concentration), which is then compared against established cut-offs. There is no "human-in-the-loop" component in the interpretation of the kit's raw result in the context of this performance assessment, although human laboratory personnel perform the assay and clinical interpretation of results based on screening guidelines.
7. The Type of Ground Truth Used
The ground truth used was clinical diagnosis/outcomes data for Congenital Adrenal Hyperplasia (CAH). The document refers to "confirmed CAH case samples" and "clinically confirmed CAH samples."
8. The Sample Size for the Training Set
The document does not provide details of a specific "training set" in the context of machine learning. For an IVD kit like this, "training" typically refers to the assay development and validation process (e.g., antibody selection, calibration curve establishment, optimization of reagents), which is not quantified by a sample size in the same way as an AI algorithm's training data. The description indicates a "new antiserum in B024," which suggests a re-optimization or re-development that would have involved internal validation and method development.
9. How the Ground Truth for the Training Set was Established
As noted above, a distinct "training set" with ground truth in the AI/ML sense is not applicable here. The ground truth for developing and validating the assay's components (like the new antiserum) would have involved:
- Characterization of pure steroid compounds for cross-reactivity assessment.
- Use of spiked samples with known concentrations of 17-OHP to establish linearity, analytical sensitivity, and precision.
- Reference methods or established clinical samples during assay development and optimization to ensure it accurately measures 17-OHP.
Ask a specific question about this device
Page 1 of 1