MAUDE Adverse Event Report: ROCHE DIAGNOSTICS NH3L AMMONIA; ENZYMATIC METHOD, AMMONIA

Catalog Number 20766682322

Device Problem High Test Results (2457)

Patient Problem No Consequences Or Impact To Patient (2199)

Event Date 12/01/2017

Event Type  malfunction  

Manufacturer Narrative

The investigation is ongoing.This event occurred in (b)(6).

Event Description

The initial reporter received questionable nh3l ammonia results for three patients from cobas 8000 cobas c 702 module serial number (b)(4).The customer suspected an interference.Data was only provided for two of the patients.Patient 1: the specific date of this event was not known, therefore (b)(6) 2017 was used.In (b)(6) 2017, the child patient had liver failure and received a liver transplant.After surgery she had tpn (total parenteral nutrition) with smof (lipids) and numeta (a.O.Amino acids/trace elements, but not additional lipids).With the nh3l assay, high ammonia concentrations were reported, around 120 mol/l over several days.Dialysis (cvvh) was started because of kidney failure, but ammonia levels did not decrease.Six days post liver transplant the patient's the initial ammonia result 173 umol/l.The laboratory technician made a 1:1 dilution and the result was 90 umol/l.He suspected a collection error, requested a new sample, and observed exactly the same.No specific data was provided for the new sample.For a new sample on (b)(6) 2019, the initial result was 73.2 umol/l and was reported outside of the laboratory.The same sample was repeated later that day and the result was 58.0 umol/l.The same sample was repeated using nh3l ammonia gen 2 reagent and the result was 15.5 umol/l.Patient 2: on (b)(6) 2019, the nh3l result was 130.6 umol/l, but nh3l gen 2 result was 21.4 umol/l.A 1:2 dilution was performed and the result was 27.5 umol/l.On (b)(6) 2019, the nh3l result was 130.6 umol/l, but nh3l gen 2 result was 21.3 umol/l.A 1:2 dilution was performed and the result was 55 umol/l.The questionable results were reported outside of the laboratory.

Manufacturer Narrative

On (b)(6) 2019, the customer received questionable nh3l ammonia results for one additional patient (12 months old with liver disease).The nh3l results from the cobas c702 analyzer were 52.6 mol/l and 46.0 mol/l.The nh3l2 results from the cobas c502 analyzer were 22.7 mol/land 21.6 mol/l.It was unknown if any questionable result was reported outside of the laboratory or if the patient was adversely affected.

Manufacturer Narrative

Information was provided that the customer thinks there might have been a false treatment (unnecessary dialysis) based on a too high ammonia result.Additional information about the patient, treatment, and current condition was requested.However, the customer could not provide any further information other than "at least one patient (child) that was sent to another hospital".

Manufacturer Narrative

Additional patient information was provided: patient 1 was 3 years old (nearly 4) with methylmalonic acidemia (mma).Patient 2 was a 7 year old female with methylmalonic acidemia (mma).Patient 3 ((b)(6) 2019) was a 1 year female with hepatoblastoma, treated with extended hepatectomy.Additional nh3l ammonia results were provided for patients 1 and 2.Refer to the attachment to the medwatch.- attachment: [pt-40504_additional_patient_results.Pdf].

Manufacturer Narrative

The investigation did not identify a product problem.The cause of the event could not be determined.Potential drug interference can be excluded.Since many patients are treated with tpn (total parenteral nutrition), but the phenomenon occurs with individual patients only, the interference by tpn with smof (lipids) and numeta (amino acids/trace elements, but not addition lipids) could be excluded.

• Brand Name: NH3L AMMONIA
• Type of Device: ENZYMATIC METHOD, AMMONIA
• Manufacturer (Section D): ROCHE DIAGNOSTICS; 9115 hague road; indianapolis IN 46250 0457
• MDR Report Key: 9353289
• MDR Text Key: 219406645
• Report Number: 1823260-2019-04150
• Device Sequence Number: 1
• Product Code: JIF
• Combination Product (y/n): N
• PMA/PMN Number: K972250
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: foreign,health professional,u
• Type of Report: Initial,Followup,Followup,Followup,Followup
• Report Date: 08/24/2020

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 11/21/2019
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Catalogue Number: 20766682322
• Device Lot Number: ASKU
• Was Device Available for Evaluation?: Yes
• Date Manufacturer Received: 11/01/2019
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1