(27 days)
The ALPI method is an in vitro diagnostic test for the quantitative measurement of alkaline phosphatase in human serum and plasma on the Dimension Vista® System. Measurements of alkaline phosphatase or its isoenzymes are used in the diagnosis and treatment of liver, bone, parathyroid, and intestinal diseases.
ALPI CAL is an in vitro diagnostic product for the calibration of alkaline phosphatase (ALPI) method on the Dimension Vista® System.
The ALPI method employs alkaline phosphatase that catalyzes the transphosphorylation of pnitrophenylphosphate (p-NPP) to p-nitrophenol (p-NP) in the presence of the transphosphorylating buffer, 2 amino-2-methyl-1-propanol (AMP). The reaction is enhanced through the use of magnesium and zinc ions. The change in absorbance at 405 nm due to the formation of p-NP is directly proportional to the ALP activity, since other reactants are present in non-rate limiting quantities and is measured using a bichromatic (405, 510 nm) rate technique.
p-NPP + AMP -> p-NP + AMP + PO4 (reaction conditions: pH 10.25, Mg/Zn)
The ALPI CAL is a one (1) level, liquid calibrator. It is packaged as a kit of three vials of Calibrator A (Level 2) with 1.0 mL per vial. The product matrix is a human serum albumin based product containing alkaline phosphatase from porcine kidney. Level 1 is a zero level (system water). Level 2 contains alkaline phosphatase at 1000 U/L.
This product is sold separately from the Flex® reagent cartridge. Values are assigned to new lots from a Masterpool that is from an International Federation of Clinical Chemistry (IFCC) reference.
Here's a breakdown of the acceptance criteria and study information for the Dimension Vista® Alkaline Phosphatase Flex® reagent cartridge (ALPI) and Calibrator (ALPI CAL), based on the provided 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Characteristic | Acceptance Criteria (Implied by Predicate/Guideline) | Reported Device Performance (Dimension Vista® ALPI) |
|---|---|---|
| Method Comparison | Demonstrated substantial equivalence to predicate device (ADVIA® Chemistry Alkaline Phosphatase AMP assay) with acceptable correlation statistics (slope near 1, intercept near 0, high correlation coefficient). While specific numerical acceptance criteria for slope, intercept, and 'r' aren't explicitly stated as "acceptance criteria," the predicate comparison aims to show the new device performs similarly. | Slope: 1.05 |
| Serum/Plasma Comparison | Demonstrated equivalency between serum and lithium heparin plasma with acceptable linear regression statistics (slope near 1, intercept near 0, high correlation coefficient). | Slope: 1.02 |
| Reference Interval | Establishment of a clinically appropriate reference interval for healthy adults. | 45-117 U/L [0.75 – 1.95 µkat/L] |
| Precision | Consistent and reproducible results across various levels, as evaluated by CLSI EP5-A2 with acceptable repeatability and within-lab standard deviation (SD) and coefficient of variation (%CV). No explicit numerical acceptance criteria for %CV or SD are provided, but the presented data demonstrates good precision with low CVs. | Repeatability: |
- Level 1: 1.0 U/L (2.9% CV)
- Level 2: 1.9 U/L (1.2% CV)
- Level 3: 4.0 U/L (1.3% CV)
- Serum Pool 1: 1.3 U/L (1.7% CV)
- Serum Pool 2: 13.6 U/L (1.6% CV)
Within-Lab: - Level 1: 1.4 U/L (4.1% CV)
- Level 2: 3.1 U/L (2.0% CV)
- Level 3: 4.6 U/L (Not legible in original doc)
- Serum Pool 1: 1.5 U/L (1.9% CV)
- Serum Pool 2: 15.0 U/L (1.8% CV) |
| Linearity/Measuring Range | Established linear range according to CLSI EP-6A, ensuring accurate measurements within the stated range. The curve fit (R-squared) should show high linearity. | 10 - 1000 U/L
Linearity Assessment: y = 1.010x + 3.461, R-squared = 0.999 |
| Analytical Specificity/Interferences | Bias due to interferents (hemoglobin, bilirubin, lipemia) should be less than 10%. | Bias
§ 862.1050 Alkaline phosphatase or isoenzymes test system.
(a)
Identification. An alkaline phosphatase or isoenzymes test system is a device intended to measure alkaline phosphatase or its isoenzymes (a group of enzymes with similar biological activity) in serum or plasma. Measurements of alkaline phosphatase or its isoenzymes are used in the diagnosis and treatment of liver, bone, parathyroid, and intestinal diseases.(b)
Classification. Class II.