N ANTISERUM TO HUMAN ALBUMIN

Additional Manufacturer Narrative

SIEMENS FILED THE INITIAL MDR 9610806-2019-00044 ON 18-APR-2019. ADDITIONAL INFORMATION (26-APR-2019): SIEMENS HEADQUARTERS SUPPORT CENTER (HSC) ANALYZED SUBMITTED ATELLICA NEPH 630 SAVE DATA FILE AND DETERMINED THAT THERE WAS NO INDICATION OF AN INSTRUMENT NOR A REAGENT MALFUNCTION. EACH URINE AND CEREBRAL SPINAL FLUID (CSF) SAMPLE MUST BE CENTRIFUGED PRIOR TO TESTING. SERUM AND PLASMA SAMPLES ARE AUTOMATICALLY DILUTED 1:400 WITH N DILUENT AND MEASURED. ALBUMIN IN SERUM AND CSF CAN ALSO BE ANALYZED USING A SINGLE REFERENCE CURVE, PROVIDED THAT THE APPROPRIATE SAMPLE DILUTION IS SELECTED MANUALLY. THE DILUTED SAMPLES MUST BE MEASURED WITHIN FOUR HOURS. IF THE RESULTS OBTAINED ARE OUTSIDE THE MEASURING RANGE, THE ASSAY CAN BE REPEATED USING A HIGHER OR LOWER DILUTION OF THE SAMPLE. THE CAUSE OF THE DISCORDANT FALSELY, ELEVATED ALBUMIN RESULT IS DUE TO THE USER NOT FOLLOWING THE INSTRUCTIONS FOR USE (IFU) OF N ANTISERUM TO HUMAN ALBUMIN AND IGG. THE RELATED CHAPTER, "ASSAY OF SPECIMEN", INSTRUCTS THE USER TO DILUTE SPECIMENS WITH N DILUENT. THE CUSTOMER USED SODIUM CHLORIDE (NACL). THE SYSTEM IS WORKING ACCORDING THE SPECIFICATIONS. THE CONCLUSION CODE WAS UPDATED TO REFLECT THE ADDITIONAL INFORMATION. SUPPLEMENTAL MDR 9610806-2019-00043_S1 WAS FILED FOR THE SAME EVENT.

Additional Manufacturer Narrative

THE CUSTOMER CONTACTED A SIEMENS CUSTOMER CARE CENTER (CCC) AND REPORTED THAT THEY OBSERVED A DIFFERENCE IN ALBUMIN/CSF RESULTS FROM TWO DIFFERENT DILUTIONS ON A PATIENT SAMPLE ON THE ATELLICA NEPH 630 SYSTEM. SIEMENS ANALYZED THE PROVIDED CUSTOMER SAVE DATA FILE. SIEMENS DETERMINED THAT THERE WAS NO INSTRUMENT OR REAGENT MALFUNCTION. ALBUMIN IN SERUM AND CSF CAN ALSO BE ANALYZED USING A SINGLE REFERENCE CURVE, PROVIDED THAT THE APPROPRIATE SAMPLE DILUTION IS SELECTED MANUALLY. IF THE RESULTS OBTAINED ARE OUTSIDE THE MEASURING RANGE, THE ASSAY CAN BE REPEATED USING A HIGHER OR LOWER DILUTION OF THE SAMPLE AS PER THE SYSTEM'S INSTRUCTION MANUAL. THE CUSTOMER DILUTED AFFECTED SAMPLES WITH NACL. THE CAUSE OF THE DISCORDANT ALBUMIN RESULT IS UNKNOWN. THE INSTRUMENT IS PERFORMING ACCORDING TO SPECIFICATIONS. NO FURTHER EVALUATION OF THIS DEVICE IS REQUIRED. MDR 9610806-2019-00043 WAS FILED FOR THE SAME EVENT.

Description of Event or Problem

CUSTOMER OBSERVED A DIFFERENCE BETWEEN TWO DILUTED RESULTS FROM THE SAME CEREBRAL SPINAL FLUID (CSF) SAMPLE ON THE ATELLICA NEPH 630 SYSTEM USING THE N ANTISERUM TO ALBUMIN REAGENT (LOT 153939B) ON TWO SEPARATE DATES. THE ORIGINAL SAMPLE RESULT WAS FLAGGED FOR TURBIDITY FOR IMMUNOGLOBULIN G (IGG) AND CARRIED NO FLAG FOR ALBUMIN. THE INITIAL ALBUMIN RESULTED IN A VALUE GREATER THAN THE MEASURING RANGE WITH AN INITIAL DILUTION OF 1:5, THE SAMPLE WAS REPEATED WITH A DILUTION OF 1.2 AND YIELDED LOWER VALUES. THE SAME SAMPLE WAS REPEATED TWO DAYS LATER USING THE SAME INSTRUMENT AND REAGENT IN 1:2 MANUAL DILUTION WITH SODIUM CHLORIDE (NACL), WHICH RESULTED IN A LOWER VALUE. THE CUSTOMER DID NOT REPORT ANY OF THE RESULTS OBTAINED FOR THIS SAMPLE TO THE PHYSICIAN BECAUSE THE CORRECT RESULT IS UNKNOWN. THERE ARE NO KNOWN REPORTS OF PATIENT INTERVENTION OR ADVERSE EVENT DUE TO THE ELEVATED ALBUMIN RESULTS.