When a reagent bottle is out of contact with the corresponding sensor, the dialog box, which shows the reagent type, concentration and use history is displayed on the instrument monitor; and the bottle state is set to .When a user selects a bottle from the table displayed in the dialog box, three (3) radio buttons are displayed as follows: the option, which should be selected if no change has been made to the reagent in the bottle; the option, which should be selected when a small amount of fresh reagent of the same type has been added to bring up the reagent level in the bottle and the option, which should only be selected when the entire contents of the reagent bottle have been replaced.In multiple instances recorded in the instrument logs, a user incorrectly selected the option rather than the option.Selection of the option results in opening of the dialog box with the following message displayed: "do you want to use the default concentration for this reagent?" a user affirmed that the xylene concentration in bottle 11 was to be set to the default value of 100% at 04:01am on (b)(6) 2016, 04:13am on (b)(6) 2016, 04:24am on (b)(6) 2016 and at 05:17am on (b)(6) 2016; and the ethanol concentration in bottle 8 was to be set to the default value of 100% at 18:48pm on (b)(6) 2016.However, the actual reagent concentration in bottles 11 (xylene) and 8 (ethanol) remained as 69.4% and 78.9% respectively because neither of these bottles had been removed from the instrument for sufficient time to replace the reagent.It was determined that the quality of tissue processing from the following six (6) protocols would have been adversely affected by the incorrect user action of resetting the properties of bottles 11 (xylene) and 8 (ethanol) without replacing the reagent in either instance: the "factory 12hr xylene standard" protocol started in retort a at 19:02pm on (b)(6) 2016; the "factory 12hr xylene standard" protocol started in retort a at 19:03pm on (b)(6) 2016; the "factory 12hr xylene standard" protocol started in retort a at 18:49pm on (b)(6) 2016; the "factory 12hr xylene standard" protocol started in retort b at 20:47pm on (b)(6) 2016; and the "alcohol (2) to xylene" protocol started in retort a at 08:46am on (b)(6) 2016 and the "factory 12hr xylene standard" protocol started in retort a at 19:05pm on (b)(6) 2016.The instrument software uses reagent concentration to select reagent stations when a protocol is scheduled.The reagent station with the lowest (in -threshold) concentration of a reagent group or type is selected for the first step using that reagent group or type; and reagent stations of increasing concentration are used for the succeeding processing steps of the reagent group or type.Reagent with the highest concentration is always used for the final processing step of a reagent group or type before changing to another reagent group or type.As a consequence, bottle 11 (xylene) was used for the final clearing steps in a total of six (6) protocols between (b)(6) 2016; and bottle 8 (ethanol) was used for the final dehydration step in a total of three (3) protocols between (b)(4) 2016.The minimum final reagent concentration required for ethanol and xylene is 98% and 95% respectively.The consequences of using ethanol at less than the minimum required for the final dehydration in a protocol and/or using xylene at less than the minimum required for the final clearing step in a protocol is re-introduction of water into the tissue which cannot be displaced in subsequent processing steps; and contamination of reagents used in the subsequent processing steps, ultimately resulting in sub-optimal tissue processing.The root cause of the sub-optimal tissue processing reported was a combination of the following use errors: a user incorrectly selected the option rather than the option when the dialog box was displayed on the instrument monitor at 04:01am on (b)(6) 2016.The dialog box was displayed when bottle 11 (xylene) briefly moved out of contact with the corresponding sensor and contact was subsequently re-established.The option should only be selected when the entire contents of a reagent bottle have been replaced with fresh reagent as detailed in section 5.4.4 of the peloris/peloris ll user manual.In this instance, no change had been made to the reagent in bottle 11 (xylene).This incorrect user action was subsequently repeated on several other occasions when bottle 11 (xylene) briefly moved out of contact with the corresponding sensor and contact was subsequently re-established.The root cause of bottle 11 detaching from the corresponding sensor on multiple occasions on (b)(6) 2016 could not be unequivocally determined from the information available.A user also failed to complete manual replacement of the reagent in bottle 8 (ethanol) in accordance with the manufacturer instructions detailed in the leica peloris/peloris ll user manual, which contains the following specific warning: "always change reagents when prompted.Always update station details correctly - never update the details without replacing the reagent.Failure to follow these directives can lead to tissue damage or loss.".
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Leica biosystems received a complaint that a portion of the tissue samples processed overnight on both (b)(6) 2016 were over-processed.The complainant advised that tissue from a total of 20 cases had been adversely impacted and biopsy samples and large surgical specimens are processed together.On (b)(6) 2016, a leica field support specialist (fss) attended the laboratory in order to investigate the circumstances involved in the complaint and to provide applications support.The fss measured the ethanol concentration in bottles 3-10 inclusive using a hydrometer; and found that the variance between the measured concentration and that calculated by the instrument software, which is based on data entered by the user, exceeded the acceptable limit in bottle 8 only.The measured ethanol concentration in bottle 8 was 85%; and the corresponding calculated concentration was 99%.The complainant advised the fss that all reagents, including waxes, on the instrument would be replaced; and that a validation run(s) using non-diagnostic tissue samples would be performed, in order to assess the quality of tissue processing before processing any further diagnostic samples.The fss provided refresher peloris training, which focused on completion of the reagent replacement process in accordance with the manufacturer instructions detailed in the leica peloris/peloris ii user manual, to the laboratory staff.On-site assessment of the operation and function of the instrument was conducted by a leica (b)(4) field service engineer (fse) on (b)(6) 2016.The fse performed system verification tests for which all results were satisfactory, and the instrument was found to be operating within specification.On 06 july 2016, leica biosystems (b)(4) received information that all tissue samples exhibiting sub-optimal processing were diagnosable.
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