(124 days)
The STA® - Liatest® D-Di kit is an immuno-turbidimetric assay for the quantitative determination of D-dimer in venous plasma (in 3.2% sodium citrate) for use on STA-R®, STA Compact® and STA Satellite® analyzers by professional laboratory personnel. The STA® - Liates® D-Di is intended for use in conjunction with a clinical pretest probability (PTP) assessment model to exclude pulmonary embolism (PE) and as an aid in the diagnosis of deep venous thrombosis (DVT) in outpatients suspected of PE or DVT.
STA® - Liatest® D-Di kit contains: 6 x 5-ml vials of ready-for-use Tris buffer and 6 x 6-ml vials of a suspension of microlatex particles coated with two different mouse monoclonal anti-human D-dimer antibodies (8D2 and 2.1.16) stabilized with bovine albumin.
The test principle is based on the change in turbidity of a microparticle suspension that is measured by photometry. A suspension of latex microparticles, coated by covalent bonding with monoclonal antibodies specific for D-dimer is mixed with the test plasma for which the D-dimer level is to be assayed. An antigen-antibody reaction takes place, leading to an agglutination of the latex microparticles which causes an increase in turbidity of the reaction medium. This increase in turbidity is reflected by an increase in absorbance, the latter being measured photometrically. The increase in absorbance is a function of the D-dimer level present in the test sample.
Here's a breakdown of the acceptance criteria and the study details for the STA® - Liatest® D-Di device, based on the provided document:
Acceptance Criteria and Reported Device Performance
The acceptance criteria for the STA® - Liatest® D-Di device are implicitly tied to its ability to
safely rule out Pulmonary Embolism (PE) in patients with low or moderate pretest probability (PTP).
The key performance metric for exclusion of PE is the Negative Predictive Value (NPV).
| Performance Metric | Acceptance Criteria (Implied by Study) | Reported Device Performance (Overall Study Population) |
|---|---|---|
| Sensitivity for PE | High sensitivity to minimize false negatives | 97.0 % (95% CI: 91.6 % - 99.4 %) |
| NPV for PE Exclusion | High NPV to safely rule out PE | 99.7 % (95% CI: 99.2 % - 100.0 %) |
| Specificity for PE | (No explicit threshold, but reported for completeness) | 75.5 % (95% CI: 72.8 % - 78.1 %) |
| PPV for PE | (No explicit threshold, but reported for completeness) | 25.5 % (95% CI: 23.5 % - 27.7 %) |
| Clinical Cut-off | D-dimer level |
§ 864.7320 Fibrinogen/fibrin degradation products assay.
(a)
Identification. A fibrinogen/fibrin degradation products assay is a device used to detect and measure fibrinogen degradation products and fibrin degradation products (protein fragments produced by the enzymatic action of plasmin on fibrinogen and fibrin) as an aid in detecting the presence and degree of intravascular coagulation and fibrinolysis (the dissolution of the fibrin in a blood clot) and in monitoring therapy for disseminated intravascular coagulation (nonlocalized clotting in the blood vessels).(b)
Classification. Class II (performance standards).