PMS2 (A16-4) MM PAB

Additional Manufacturer Narrative

THE SERIAL NUMBER OF THE ANALYZER IS (B)(4). THE CUSTOMER CONFIRMED ISSUES DURING THE PRE-ANALYTICAL PHASE, SPECIFICALLY REGARDING IMPROPER SAMPLE FIXATION FOR PATIENT 1'S SLIDES. THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THERE WAS AN ALLEGATION OF QUESTIONABLE RESULTS WITH THE PMS2 (A16-4) MM PAB AND MLH1 (M1) MM PAB ASSAYS FOR TWO PATIENT SAMPLES TESTED ON A BENCHMARK ULTRA PLUS INSTRUMENT. THIS MEDWATCH WILL APPLY TO THE PMS2 (A16-4) MM PAB ASSAY. PLEASE REFER TO THE MEDWATCH WITH A1. PATIENT IDENTIFIER (B)(6) FOR INFORMATION RELATED TO THE MLH1 (M1) MM PAB ASSAY. PATIENT 1: THE STAINING RESULTS WERE POSITIVE FOR PMS2 AND MLH1. THE STAINING RESULTS AT A DIFFERENT LAB WERE NEGATIVE. PATIENT 2: THE STAINING RESULTS WERE NEGATIVE FOR PMS2 AND MLH1. THE REPEAT STAINING RESULT WAS POSITIVE FOR PMS2. THE TESTS WERE REPEATED BECAUSE THE PATHOLOGIST REVIEWED THE SAMPLES AGAIN AND DETERMINED THAT THE STAINING WAS AMBIGUOUS AND THEY SHOULD BE CLASSIFIED AS "UNINTERPRETABLE/UNVALUABLE."

Additional Manufacturer Narrative

MEDWATCH FIELD D4 LOT NO WAS UPDATED. THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM. THE PROBABLE ROOT CAUSE FOR THE INCONSISTENT STAINING WAS DETERMINED TO BE RELATED TO THE DEVIATIONS FROM THE METHOD SHEET PROTOCOL, COMBINED WITH POOR FIXATION/PRE-ANALYTICAL FACTORS.