NH3L2
Received Dec 18, 2023 · Event occurred Jan 1, 2003
Report 1823260-2023-04086 · MDR key 18347471
Device
Product problems
- Incorrect, Inadequate or Imprecise Result or Readings
- High Test Results
- Non Reproducible Results
- Incorrect, Inadequate or Imprecise Result or Readings
- High Test Results
- Non Reproducible Results
Patient
NA · Female
- No Clinical Signs, Symptoms or Conditions
- No Clinical Signs, Symptoms or Conditions
Narrative
Additional Manufacturer Narrative
THE INVESTIGATION FOUND THAT THE PATIENT WAS TAKING ERWINASE. PER ERWINASE LABELING, THE DRUG CAN LEAD TO AN INCREASE IN AMMONIA IN THE BLOOD IN 1% OF PATIENTS. THE ROOT CAUSE OF THE EVENT WAS FOUND TO BE CONSISTENT WITH ERWINASE INTERFERENCE. NO PRODUCT PROBLEM WAS IDENTIFIED.
Description of Event or Problem
THERE WAS AN ALLEGATION OF QUESTIONABLE PLASMA NH3L AMMONIA RESULTS FOR 4 PATIENT SAMPLES ON A HITACHI 917 ANALYZER. FOR SAMPLE 1, THE INITIAL NH3 RESULT WAS 163 UMOL/L. THE SAMPLE WAS REPEATED IN THREE 20 MINUTE INTERVALS AND THE RESULTS WERE 235 UMOL/L, 292 UMOL/L, AND 315 UMOL/L. FOR SAMPLE 2, THE INITIAL NH3 RESULT WAS 209 UMOL/L. THE SAMPLE WAS REPEATED IN THREE 20 MINUTE INTERVALS AND THE RESULTS WERE 272 UMOL/L, 351 UMOL/L, AND 383 UMOL/L. FOR SAMPLE 3, THE INITIAL NH3 RESULT WAS 201 UMOL/L. THE REPEAT RESULT WAS 276 UMOL/L. FOR SAMPLE 4, THE INITIAL NH3 RESULT WAS 259 UMOL/L. THE REPEAT RESULT WAS 339 UMOL/L.
Additional Manufacturer Narrative
THE ANALYZER SERIAL NUMBER WAS NOT PROVIDED. THE STUDY ALLEGED THAT ANTINEOPLASTIC THERAPY WITH ASPARAGINASE CAN AFFECT AMMONIA RESULTS IN PLASMA SAMPLES. THE STUDY STATED THAT ASPARAGINASE CONVERTS THE AMINO ACID ASPARAGINE TO ASPARTIC ACID AND AMMONIA AND IT APPEARS FROM THEIR OBSERVATIONS THAT SOME AMMONIA PRODUCTION OCCURS IN VITRO AFTER SAMPLE COLLECTION. THE INVESTIGATION IS ONGOING.