Catalog Number: 04491815190

SYSTEM INFORMATION

For cobas e 411 analyzer: test number 221

INTENDED USE

Immunoassay for the in vitro quantitative determination of troponin T in human serum and plasma. This assay can be used as an aid in the differential diagnosis of acute coronary syndrome to identify necrosis, e.g. acute myocardial infarction. The test is further indicated for the risk stratification of patients presenting with acute coronary syndrome and for cardiac risk in patients with chronic renal failure. The test may also be useful for the selection of more intensive therapy and intervention in patients with elevated levels of cardiac troponin T.

RESULTS ARE DETERMINED VIA A CALIBRATION CURVE WHICH IS INSTRUMENT-SPECIFICALLY GENERATED BY 2‑POINT CALIBRATION AND A MASTER CURVE PROVIDED VIA THE REAGENT BARCODE OR E‑BARCODE.

STORAGE AND STABILITY

Store at 2‑8 °C.

CALIBRATION

Traceability: The Elecsys Troponin T assay (4th generation,  04491815) has been standardized against the Elecsys Troponin T STAT assay (4th generation,  04660307). This in turn was originally standardized against the Enzymun‑Test Troponin T (CARDIAC T) method.

EVERY ELECSYS REAGENT SET HAS A BARCODED LABEL CONTAINING SPECIFIC INFORMATION FOR CALIBRATION OF THE PARTICULAR REAGENT LOT. THE PREDEFINED MASTER CURVE IS ADAPTED TO THE ANALYZER USING THE RELEVANT CALSET.

CALIBRATION MUST BE PERFORMED ONCE PER REAGENT LOT USING FRESH REAGENT (I.E. NOT MORE THAN 24 HOURS SINCE THE REAGENT KIT WAS REGISTERED ON THE ANALYZER).

RENEWED CALIBRATION IS RECOMMENDED AS FOLLOWS:

CONTROLS FOR THE VARIOUS CONCENTRATION RANGES SHOULD BE RUN INDIVIDUALLY AT LEAST ONCE EVERY 24 HOURS WHEN THE TEST IS IN USE, ONCE PER REAGENT KIT, AND FOLLOWING EACH CALIBRATION.

LIMITS AND RANGES

Measuring range

MEASURING RANGE

0.010‑25.0 µg/L or ng/mL (defined by the lower detection limit and the maximum of the master curve). Values below the lower detection limit are reported as < 0.010 µg/L (ng/mL). Values above the measuring range are reported as > 25.0 µg/L or ng/mL (or up to 250 µg/L or ng/mL for 10‑fold diluted samples).

0.010‑25.0 ΜG/L OR NG/ML (DEFINED BY THE LOWER DETECTION LIMIT AND THE MAXIMUM OF THE MASTER CURVE). VALUES BELOW THE LOWER DETECTION LIMIT ARE REPORTED AS < 0.010 ΜG/L (NG/ML). VALUES ABOVE THE MEASURING RANGE ARE REPORTED AS > 25.0 ΜG/L OR NG/ML (OR UP TO 250 ΜG/L OR NG/ML FOR 10‑FOLD DILUTED SAMPLES).

LOWER LIMITS OF MEASUREMENT

Lower detection limit of the test

SAMPLES WITH TROPONIN T CONCENTRATIONS ABOVE THE MEASURING RANGE CAN BE DILUTED WITH DILUENT UNIVERSAL. THE RECOMMENDED DILUTION IS 1:10 (EITHER AUTOMATICALLY BY THE ANALYZERS OR MANUALLY). THE CONCENTRATION OF THE DILUTED SAMPLE MUST BE > 1.00 ΜG/L (NG/ML).

THE LOWEST CONCENTRATION WITH A CV LESS THAN OR EQUAL TO 10 % WITH THE ELECSYS TROPONIN T ASSAY WAS 0.030 ΜG/L (NG/ML) (INTERMEDIATE WITHIN LOT PRECISION) OR 0.060 ΜG/L (NG/ML) (INTERMEDIATE LOT TO LOT PRECISION).

Precision was determined using Elecsys reagents, pooled human sera and controls in a modified protocol (EP5‑A) of the CLSI (Clinical and Laboratory Standards Institute): 6 times daily for 10 days (n = 60); repeatability on MODULAR ANALYTICS E170 analyzer, n = 21. The following results were obtained:

SPECIFIC PERFORMANCE DATA

Representative performance data on the analyzers are given below.

PRECISION

Precision was determined using Elecsys reagents, pooled human sera and controls in a modified protocol (EP5‑A) of the CLSI (Clinical and Laboratory Standards Institute): 6 times daily for 10 days (n = 60); repeatability on MODULAR ANALYTICS E170 analyzer, n = 21. The following results were obtained:

PRECISION WAS DETERMINED USING ELECSYS REAGENTS, POOLED HUMAN SERA AND CONTROLS IN A MODIFIED PROTOCOL (EP5‑A) OF THE CLSI (CLINICAL AND LABORATORY STANDARDS INSTITUTE): 6 TIMES DAILY FOR 10 DAYS (N = 60); REPEATABILITY ON MODULAR ANALYTICS E170 ANALYZER, N = 21. THE FOLLOWING RESULTS WERE OBTAINED:

INTERMEDIATE PRECISION

INTERMEDIATE PRECISION

METHOD COMPARISON

A comparison of the Elecsys Troponin T assay (y) with the Elecsys Troponin T STAT assay (x) using clinical samples gave the following correlations:

BABLOK W, PASSING H, BENDER R, ET AL. A GENERAL REGRESSION PROCEDURE FOR METHOD TRANSFORMATION. APPLICATION OF LINEAR REGRESSION PROCEDURES FOR METHOD COMPARISON STUDIES IN CLINICAL CHEMISTRY,