TINA-QUANT D-DIMER GEN. 2

Additional Manufacturer Narrative

THE C501 ANALYZER SERIAL NUMBER IS (B)(6). THE PATIENT'S SAMPLE WAS REQUESTED FOR INVESTIGATION. THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THE INITIAL REPORTER STATED THEY RECEIVED QUESTIONABLE RESULTS FOR ONE PATIENT TESTED WITH TINA-QUANT D-DIMER GEN. 2 ON A COBAS 6000 C501 MODULE. THE PATIENT WAS ALLEGED TO BE ASYMPTOMATIC, BUT THE C501 VALUES ARE ELEVATED. ON AN UNKNOWN DATE IN 2024, A FIRST SAMPLE COLLECTED FROM THE PATIENT RESULTED IN A D-DIMER VALUE OF 6.31 UG/ML WHEN TESTED ON THE C501 ANALYZER. OTHER TUBE TYPES COLLECTED DURING THE SAMPLE COLLECTION CONFIRMED THE SAME VALUE WITHIN A FEW DAYS OF THE INITIAL MEASUREMENT. THE TUBE TYPES INCLUDED "FL MEDICAL" SODIUM CITRATE PLASMA AND "VACUTEST CITRATE" PLASMA. A SECOND SAMPLE WAS COLLECTED FROM THE PATIENT ON (B)(6) 2025 AND TESTED ON THE C501 ANALYZER, RESULTING IN A D-DIMER VALUE OF 7.81 UG/ML. THE TUBE USED WAS "VACUTEST CITRATE". AN ALIQUOT OF THE SAMPLE WAS FROZEN AND SENT TO ANOTHER LABORATORY FOR TESTING ON A SYSMEX CS 5100 ANALYZER, RESULTING IN A D-DIMER VALUE OF < 190 UG/L (< 0.190 UG/ML). ON (B)(6) 2025, A FROZEN ALIQUOT OF THE SECOND SAMPLE WAS THAWED AND REPEATED ON THE C501 ANALYZER, RESULTING IN A D-DIMER VALUE OF 7.82 UG/ML. THIS ALIQUOT WAS SENT TO OTHER LABORATORIES FOR TESTING. WHEN ANOTHER LABORATORY REPEATED IT USING THE VIDAS BIOMERIEUX ELFA METHOS, RESULTING IN A D-DIMER VALUE OF 480 NG/ML (0.48 UG/ML). WHEN ANOTHER LABORATORY REPEATED IT USING THE CITEST FLUORESCENSE TEST, THE D-DIMER VALUE WAS 0.19 UG/ML (NEGATIVE).

Additional Manufacturer Narrative

CALIBRATION AND CONTROLS WERE ACCEPTABLE. THE PATIENT'S SAMPLE WAS PROVIDED FOR INVESTIGATION. INVESTIGATIONS HAVE DETERMINED THE SAMPLE CONTAINS AN INTERFERING FACTOR. THERE IS MOST LIKELY A HETEROPHILE ANTIBODY INTERFERENCE, AS IMMUNOGLOBULINS AND KAPPA/LAMBDA RESULTS WERE WITHIN REFERENCE RANGES, AND RF WAS REPORTED AS RECOVERING BELOW THE MEASURING RANGE OF THE ASSAY. THE ISSUE IS CONSIDERED A RARE CASE OF NON-SPECIFIC AGGLUTINATION. THE INVESTIGATION DID NOT IDENTIFY A PRODUCT ISSUE. PLEASE NOTE THAT TINA-QUANT D-DIMER GEN. 2 IS NOT APPROVED FOR USE IN THE UNITED STATES NOR IS IT LIKE OR SIMILAR TO A PRODUCT APPROVED FOR USE IN THE UNITED STATES.