COBAS 6000 C501MODULE

Description of Event or Problem

THE CUSTOMER ALLEGED QUESTIONABLE RESULTS WHEN PERFORMING A CHEMISTRY PANEL ON 1 PATIENT SAMPLE. RESULTS FOR: - ASPARTATE AMINOTRANSFERASE ACC. TO IFCC WITHOUT PYRIDOXAL PHOSPHATE ACTIVATION (AST), CREATININE PLUS VER.2 (CREAT), GLUCOSE HK (GLU), TOTAL PROTEIN GEN.2 (TP), AND ISE INDIRECT K+ FOR GEN.2 (K+) WERE FOUND TO BE ERRONEOUS AND WERE REPORTED OUTSIDE THE LABORATORY. ON (B)(6) 2011 THE FOLLOWING RESULTS WERE OBTAINED FROM AN ALIQUOT OF A SAMPLE DRAWN AT 1105: AST = 11 U/L , CREAT = 3.3 MG/DL, GLU = 79 MG/DL, TP = 5.1 G/DL, K+ = 8.3 MMOL/L. BASED ON THE HIGH K+, THE PATIENT WAS ADMITTED TO THE HOSPITAL, TREATED WITH KAYEXALATE AND HYDROCHLOROTHIAZIDE, AND AN ULTRASOUND WAS PERFORMED. A SECOND BLOOD COLLECTION WAS PERFORMED ON (B)(6) 2011 AT 2100. THE K+ WAS 3.3 MMOL/L. A THIRD COLLECTION WAS PERFORMED ON (B)(6) 2011 AT 0605 FOR A BASIC METABOLIC PANEL WITH PHOSPHOROUS AND MAGNESIUM. THE K+ WAS 3.4 MMOL/L. ON (B)(6) 2011, A PHYSICIAN ASKED THAT THE FIRST SAMPLE BE REPEATED BECAUSE HE DID NOT BELIEVE THE RESULTS COMPARED TO THE PATIENT'S CONDITION. THE FOLLOWING RESULTS WERE OBTAINED WHEN TESTING WAS PERFORMED ON THE PRIMARY SAMPLE TUBE ON ANOTHER C501 ANALYZER, SERIAL NUMBER (B)(4): AST = 28 U/L, CREAT = 0.8 MG/DL, GLU = 41 MG/DL, TP = 6.9 G/DL, K+ = 5.0 MMOL/L. THE K+, CREAT, AND TP WERE RELEASED AS CORRECTED REPORTS. THE PATIENT WAS DISCHARGED FROM THE HOSPITAL AND WAS STABLE ON DISCHARGE. THE CUSTOMER STATED SHE COULD FIND NO NOTES IN THE PATIENT CHART THAT THE PATIENT WAS TREATED IN ANY WAY TO COUNTERACT THE KAYEXALATE. THE FOLLOWING REAGENTS WERE USED: AST: LOT NUMBER 64267601 WITH EXPIRATION DATE 07/31/2012, K+: THE CUSTOMER WAS UNABLE TO PROVIDE LOT NUMBER INFORMATION, CREAT: LOT NUMBER 64712801 WITH EXPIRATION DATE 04/30/2012, GLU: LOT NUMBER 63827801 WITH EXPIRATION DATE 04/30/2012, TP: LOT NUMBER 64301001 WITH EXPIRATION DATE 07/31/2012. THE FIELD SERVICE REPRESENTATIVE WAS UNABLE TO DETERMINE A ROOT CAUSE. HE PERFORMED PRECISION TESTING AND QUALITY CONTROLS. PRECISION TESTS PASSED AND QUALITY CONTROLS WERE WITHIN SPECIFICATIONS.

Additional Manufacturer Narrative

A SPECIFIC ROOT CAUSE WAS NOT IDENTIFIED. SINCE ONLY ONE PATIENT SAMPLE WAS AFFECTED, IT IS POSSIBLE THE ROOT CAUSE WAS A PREANALYTICAL ISSUE. THE DIAGNOSIS OF RENAL FAILURE CANNOT BE BASED ON A SINGLE RESULT OF INCREASED POTASSIUM, NOR ON A SINGLE CREATININE RESULT. A POTASSIUM OF 8.3 MMOL/L WOULD LEAD TO SEVERE BRADYCARDIA, SHOWN BY THE CLINICAL STATE OF THE PATIENT, AS WELL AS ECG OR PULSE MEASUREMENT. ALSO, A POTASSIUM OF 8.3 MMOL/L IS NOT TO BE TREATED ONLY WITH POTASSIUM LOWERING SUBSTANCES. IN THIS CASE, EVEN THOUGH NO MORE PATIENT INFORMATION WAS GIVEN, THE RESULT DID NOT FIT THE CLINICAL FINDINGS.