The Medicines and Healthcare products Regulatory Agency (MHRA), a British regulatory body, has issued an alert for reagents requiring manual handling on Hitachi’s Cobas c501/502 laboratory analyzer.
The MHRA contends that the use of insufficient volumes of reagent may lead to a false negative result that could potentially harm a patient, such as a missed diagnosis of syphilis, a delayed diagnosis of organ rejection, or a delayed diagnosis of the end of remission for malignant lymphoma patients.
The MHRA has received a report of a known syphilis-positive patient receiving a false negative test result using this combination of affected devices. Following a review of results, the hospital involved identified the possibility of obtaining a "valid" but inaccurate result where there is insufficient reagent, thereby giving a false negative result. More from the MHRA Web site:
The instrument settings downloaded via the cobas link contain instrument-specific information for the application and do not contain customer instruction for reagent preparation. If these volumes are used, reagent may deplete before the end of the run.
When running any of the assays listed above where level sensing is turned off it is possible to obtain an erroneous result without an error message.
The MHRA is advising healthcare professionals not to use the reagent volumes downloaded as instrument settings via the Cobas link for manual loading of cassettes. Their advice continues:
Confirm whether initial level sensing (ICVC) is ON or OFF with your device combination. If it is OFF, ensure that you load the volume of reagent in the cassette as set out in the current instructions for use.
If you have used the affected combination of devices consider the need to review previous results including the need to recall and retest patients.
---Maureen Kingsley, associate editor