(63 days)
The Dimension EXL High-Sensitivity Troponin I (TNIH) assay is for in vitro diagnostic use in the quantitative measurement of cardiac troponin I in human plasma using the Dimension EXL integrated chemistry system with LOCI module. The assay can be used to aid in the diagnosis of acute myocardial infarction (AMI).
The Dimension EXL TNIH assay is a homogeneous, sandwich chemiluminescent immunoassay based on LOCl® technology. The LOCI reagents include two synthetic bead reagents and two biotinylated anti-cardiac troponin I monoclonal antibody fragments. The first bead reagent (Sensibeads) is coated with streptavidin and contains photosensitizer dye. The second bead reagent (Chemibeads) is coated with a third anticardiac troponin I monoclonal antibody and contains chemilyminescent dve. Sample is incubated with Chemibeads and biotinylated antibodies to form bead-cardiac troponin Ibiotinylated antibody sandwiches. Sensibeads are added and bind to form bead-pair immunocomplexes. Illumination of the complex at 680 nm generates singlet oxygen from Sensibeads which diffuses into the Chemibeads, triggering a chemiluminescent reaction. The resulting signal is measured at 612 nm and is a direct function of the cardiac troponin I concentration in the sample. Lithium heparin plasma specimens may be used. The reagent is stored unopened at 2 -8 °C, is stable sealed on system for 30 days and opened on the system for 7 days. Calibration is performed every 21 days for a reagent lot.
Here's a summary of the acceptance criteria and study details for the Dimension EXL High-Sensitivity Troponin I (TNIH) Assay, extracted from the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Metric | Acceptance Criteria (implicit from compliance) | Reported Device Performance |
|---|---|---|
| Limit of Blank (LoB) | Consistency with claim of 1.1 pg/mL | 1.0 pg/mL |
| Limit of Detection (LoD) | Consistency with claim of 2.7 pg/mL | 1.0 - 1.8 pg/mL |
| Limit of Quantitation (LoQ) | CV ≤ 20.0% | 1.1 pg/mL (Lot-1), 2.1 pg/mL (Lot-2), 2.3 pg/mL (Lot-3). Claimed LoQ of 4.0 pg/mL. (The LoQ of 4.0 pg/mL is explicitly stated to be consistent with the data, implying it met the 20% CV criteria). |
| 10% CV Limit | CV ≤ 10.0% | 3.2 pg/mL (Lot-1), 5.3 pg/mL (Lot-2), 5.8 pg/mL (Lot-3). Claimed 10% CV limit of 12.0 pg/mL. (The 10% CV limit of 12.0 pg/mL is explicitly stated to be consistent with the data, implying it met the 10% CV criteria). |
| Precision (Repeatability %CV) | All precision goals were met (specific target not provided, but values shown are low) | Plasma 1: 2.3%, Plasma 2: 2.0%, Plasma 3: 1.8%, QC: 2.0% |
| Precision (Within-Lab %CV) | All precision goals were met (specific target not provided, but values shown are low) | Plasma 1: 6.0%, Plasma 2: 2.9%, Plasma 3: 3.0%, QC: 3.3% |
| Linearity | p-values of nonlinear terms > 0.05 OR allowable bias ≤ 10% or 4 pg/mL | Confirmed linearity from 4.0 - 25,000.0 pg/mL. |
| Interferences (Bias) | Bias exceeding 10% is considered interference. | Hemoglobin: 20,000 pg/mL) |
| Open Well Stability | p-value of regression slope ≥ 0.05 OR drift ≤ LoQ or ≤ 10% (up to 20,000 pg/mL), ≤ 13% (> 20,000 pg/mL) | Stability of reagents opened onboard the instrument was 7 days per well set. (This implies it met the acceptance criteria for 7 days). |
| Sample Stability | Lower bound of 95% CI of regression line ≤ -10% AND all data points bias ≤ -20% vs time zero | Separated samples stable for 8 hours at room temperature, 24 hours at 2-8°C, up to 40 days at or below -20°C (non-frost free), and up to 1 year at or below -70°C. (This implies these storage conditions met the specified bias criteria). |
| 99th Percentile Expected Values | Determined using non-parametric statistical method (CLSI EP28-A3c). | Overall: 60.4 pg/mL (90% CI: 43.2 to 81.3); Female: 51.4 pg/mL (90% CI: 35.6 to 109.2); Male: 76.2 pg/mL (90% CI: 42.3 to 117.0). No statistical basis for using separate values based on gender or sample type. |
| Clinical Performance | No explicit quantitative acceptance criteria provided in the extract, but the data presented supports its diagnostic utility. | Pooled Gender (60.4 pg/mL cutoff): Sensitivity ranging from 78.3% (0- |
§ 862.1215 Creatine phosphokinase/creatine kinase or isoenzymes test system.
(a)
Identification. A creatine phosphokinase/creatine kinase or isoenzymes test system is a device intended to measure the activity of the enzyme creatine phosphokinase or its isoenzymes (a group of enzymes with similar biological activity) in plasma and serum. Measurements of creatine phosphokinase and its isoenzymes are used in the diagnosis and treatment of myocardial infarction and muscle diseases such as progressive, Duchenne-type muscular dystrophy.(b)
Classification. Class II.